SW3190704_Calcs_20191011

Skyland Drive Townhomes
Site Address: South Skyland Drive
Mt. Pleasant, NC 28124
Developer: Coulston Enterprises Inc.
8332 Regent Parkway
Fort Mill, SC 29715
Stormwater Calculations
FOR:
Skyland Drive Townhomes
October 2019
American Engineering Associates — Southeast, PA.
8008 Corporate Center Drive, Suite 110
Charlotte, NC 28226
www.American-EA.com
AMERICAN
Engineering

AMERICAN
Engineering
Skyland Drive Townhomes
Stormwater Calculations
American Engineering Associates -Southeast, PA.
8008 Corporate Center Drive, Suite 110
Charlotte, NC 28226
OFFICE: 704.375.2438
www.American-EA.com
ENGINEER CERTIFICATION
I HEREBY CERTIFY THAT SPECIFICATIONS CONTAINED HEREIN AND THE ACCOMPANYING CALCULATIONS
WERE PREPARED BY ME OR UNDER MY DIRECT SUPERVISION.
SIGNED, SEALED AND DATED THIS DAY OF 0�'x0,i'U�
,;�?tlNG.ASS
,oGINEr,y1'
C y
lV Q 0 .o
O Co.
Q CERT.N0
C-3881
\ v
BY: BARRY M. FAY, PE
COMPANY: AMERICAN ENGINEERING ASSOCIA
SOUTHEAST. PA
TITLE: VICE PRESIDENT

AMERICAN
Engineering
Skyland Drive Townhomes
Stormwater Calculations
Table of Contents
American Engineering Associates -Southeast, PA.
8008 Corporate Center Drive, Suite 110
Charlotte, NC 28226
OFFICE: 704.375.2438
www.American-EA.com
Title Page No.
Narrative
1
Construction Sequence
4
Vicinity Map
7
Soils Map
8
USGS Quad Map
12
Flood Map
.....................................................................................................................
13
Storm Drain Calculations
.....................................................................................................................
System A - 10-Year Analysis Hydraflow Results
System B - 10-Year Analysis Hydraflow Results
......................................................................................................................
Time of Concentration Calculations
......................................................................................................................
Sand Filter Calculations
.....................................................................................................................
Sand Filter HydroCAD Results and Pond Report
......................................................................................................................
Erosion and Sediment Control Calculations
......................................................................................................................
Sediment Basin No. 1 - Phase 1
Sediment Basin No. 1 - Phase 2
Skimmer Sediment Basin No. 2 - Phase 1
......................................................................................................................
Sediment Basin Detail
Skimmer Sediment Basin
......................................................................................................................
Riprap Apron Calculations
......................................................................................................................

AMERICAN
Engineering
Skyland Drive Townhomes
Stormwater Calculations
American Engineering Associates -Southeast, PA.
8008 Corporate Center Drive, Suite 110
Charlotte, NC 28226
OFFICE: 704.375.2438
www.American-EA.com
Appendices
......................................................................................................................
Storm Drainage Area Map
Erosion and Sediment Control Plan Phase 1
Erosion and Sediment Control Plan Phase 2
Erosion and Sediment Control Plan Phase 3

AMERICAN
Engineering
Skyland Drive Townhomes
Stormwater Calculations
Site Narrative
American Engineering Associates -Southeast, PA.
8008 Corporate Center Drive, Suite 110
Charlotte, NC 28226
OFFICE: 704.375.2438
www.American-EA.com
The proposed project, Skyland Drive Townhomes, is a 16-lot townhome development located in Mt. Pleasant,
North Carolina. The proposed project is a 4.335-acre development, with approximately 2.93 acres of denuded
area. The proposed development is located at 991 Skyland Drive. The site's northern boundary across Skyland
Drive is an existing multi -family development. The eastern, western and southern boundaries of the site are
existing single family residential homes.
This construction site includes the clearing and grubbing of existing brush and wooded land, grading of the
existing site, and the construction of 3 multi -family townhome buildings for a total of 16 units, roads, sidewalks,
and associated improvements.
Site development and grading will occur in one stage. That stage will have three phases of erosion control. All
sediment basins have been designed for phases 1 and 2 of construction, while phase 3 will use inlet protection
and the final proposed BMPs. Erosion and sediment control measures were sized using North Carolina
Department of Environmental Quality (NCDEQ) requirements.
Pre -Development Conditions
The project site is located within an area having a zone designation X by the Federal Emergency Management
Agency (FEMA) on Flood Insurance Rate Map (FIRM) Number 3710566000K, with a date of identification of
November 16, 2018. The existing site consists mainly of an undeveloped brush and wooded land.
Stormwater runoff drains primarily toward an existing pond located in the center of the property on the
southwestern edge. There are no known flooding problems located either downstream or immediately adjacent
to the site.
Pre -developed drainage conditions can be reviewed on the drainage area maps located in the Appendix. The
existing drainage patterns consists of primarily sheet flow to the center of the property to the existing pond.
Stormwater runoff from Skyland Drive is directed to grassed swales and culverts discharging to the northwest.
The soil types identified within the project area are EnB (Enon sandy loams); and EnD (Enon sandy loams). The soil
types identified were used in determining Curve Numbers (CNs) for the onsite and offsite runoff.

AMERICAN
Engineering
Skyland Drive Townhomes
Stormwater Calculations
Post -Development Conditions
American Engineering Associates -Southeast, PA.
8008 Corporate Center Drive, Suite 110
Charlotte, NC 28226
OFFICE: 704.375.2438
www.American-EA.com
The proposed site will consist of paved streets with curb & gutter and concrete sidewalks. The 16
townhomes will consist of varying size homes with concrete driveways. Common open areas and buffers
are located throughout the proposed development. The site will be mass graded and the denuded area is
approximately 3.09 acres.
The hydrologic analysis conducted for the proposed project included the study of both onsite and offsite drainage
areas for the temporary sediment basins as well as silt fence control measures. The offsite drainage areas include
a portion of the developed and undeveloped properties north of the site. Beyond these areas, it was assumed that
drainage from other offsite areas will not route through the property. The analysis was conducted using the Soil
Conservation Service (SCS) Hydrograph Method, as outlined in SCS Technical Release 55 (TR-55). Hydrographs
calculated using Hydraflow software were used to compute peak rates of runoff for the pre -development and
post -development conditions. The temporary sediment basins have been designed to meet pre -construction
conditions for the 2-year and 1-year storm events and minimum 80% trapping efficiency as required by the
NCDEQ and the City of Charlotte.
Development of the site will include a sand filter to account for water quality and channel protection
requirements as well as providing storage for the 10-year, 25-year and 50-year storm events.
POND TRIBUTARY AREAS
Impervious
Area (AC)
Disturbed Pervious
Area (AC)
Undisturbed Pervious
Area (AC)
Total Area
(AC)
Sand Filter
1.335
0.906
0.00
2.241
The contents of this Stormwater Pollution Prevention Plan (SWPPP) were prepared for Coulston Enterprises Inc. as
the primary permittee seeking coverage under North Carolina's National Pollutant Discharge Elimination System
(NPDES) General Permit for Stormwater Discharges from Construction (CGP). Unless required by the owner, this
plan may also be used by secondary permittees to obtain coverage under the CGP.

AMERICAN
Engineering
Skyland Drive Townhomes
Stormwater Calculations
Summary
American Engineering Associates -Southeast, PA.
8008 Corporate Center Drive, Suite 110
Charlotte, NC 28226
OFFICE: 704.375.2438
www.American-EA.com
The temporary sediment basin has been designed to meet pre- and post -development requirements for the 2-
year and 10-year storm events. Furthermore, the sediment basin has been designed to achieve a minimum 80%
trapping efficiency as required by the NCDEQ and meet the latest NPDES General Permit for Stormwater
Discharge requirements.
Upon removal of the sediment basin, a level spreader device shall be installed at the proposed storm drainage
outfall. Upon exiting the level spreader device, stormwater from the various systems will discharge into an
existing Swale and eventually to the existing onsite pond.
In conclusion, due to the existing site conditions and proposed runoff control measures, the proposed project is
not anticipated to have any negative impacts on any downstream or adjacent properties.
3

AMERICAN
Engineering
Skyland Drive Townhomes
Stormwater Calculations
Construction Sequence
American Engineering Associates -Southeast, PA.
8008 Corporate Center Drive, Suite 110
Charlotte, NC 28226
OFFICE: 704.375.2438
www.American-EA.com
1. Obtain all required permits.
2. Set up an on -site pre construction conference with the erosion control inspector to discuss erosion
control measures. Failure to schedule such conference 48 hours prior to any land disturbing activity is a
violation of the town code and is subject to fine.
3. Make any required modifications to the erosion and sediment control plans. All modifications to the
erosion and sediment control plans shall be documented on the on -site approved plans.
4. Install gravel construction entrance on S. Skyland Drive.
5. Install perimeter silt fence, inlet protection, sediment basins, temporary diversion ditches and other
measures as shown on the plans clearing only as necessary to install these devices.
6. Call for on -site inspection by the erosion control inspector. When approved, the inspector issues the
grading permit and clearing and grubbing may begin.
7. Limit clearing and grubbing of the site to areas that will be mass graded. Whenever possible, existing
vegetation shall remain in place to prevent erosion of the site.
8. Begin mass grading activities. As site is graded and pads built up, contractor shall minimize the amount of
stormwater flowing over fill slopes by using diversion ditches and slope drains. Ditches and slope drains
shown on plans depict the required diversion ditches and slope drains at final pad grade. Additional
measures may be needed as progresses. Contractor shall limit drainage areas flowing to each of the
proposed basins to the maximum area that is designated for each basin. This shall be accomplished by
adjusting the proposed diversion ditches as the site is graded.
9. Contractor shall meet with the erosion control inspector prior to commencing with phase 2 erosion
control measures.
10. Install remaining silt fence, diversion ditches and other measures as shown on the phase 2 plans, clearing
only as necessary to install these devices.
11. Continue mass grading activities. As site is graded and pads built up, contractor shall minimize the amount
of stormwater flowing overfill slopes by using diversion ditches and slope drains. Ditches and slope drains
shown on plans depict the required diversion ditches and slope drains at final pad grade. Additional
measures may be needed as grading progresses. Contractor shall limit drainage areas flowing to each of
the proposed basins to the maximum area that is designated for each basin. This shall be accomplished by
adjusting the proposed diversion ditches as the site is graded.
12. Limit clearing and grubbing of site to areas that will be mass graded. Whenever possible, existing
vegetation shall remain in place to prevent erosion of the site.
13. Construction of the streets, the associated utilities, including laterals, to the completed and inspected.
14. Reconfigure silt fence as necessary.
4

AMERICAN
Engineering
Skyland Drive Townhomes
Stormwater Calculations
American Engineering Associates -Southeast, PA.
8008 Corporate Center Drive, Suite 110
Charlotte, NC 28226
OFFICE: 704.375.2438
www.American-EA.com
15. Install inlet protection and other measures as shown on phase 2 plans as the proposed storm system is
installed.
16. All areas that will go unworked for 14 days or more must be stabilized immediately. Stabilization
standards should be maintained throughout the construction process.
17. Stripped topsoil shall be stockpiled in designated areas with silt fence provided around the perimeter of
the stockpile.
18. Maintain and adjust the erosion and sediment control measures as mass grading progresses to maintain
proper erosion and sediment control.
19. The contractor shall diligently and continuously maintain all erosion control devices and structures.
20. Stabilize the site as areas are brought to grade.
21. Inspect BMPs once per every calendar week, per the NCDEQ requirements. All inspection and reporting
shall be in compliance with the NCDEQ general permit NCG010000, latest edition.
22. Contractor shall meet with the erosion control inspector prior to commencing with phase 3 erosion
control measures.
23. Install any remaining silt fence, diversion ditches and other measures as shown on the phase 3 plans,
clearing only as necessary to install these devices.
24. Townhome construction shall commence. Contractor to install any additional erosion control measures
for the individual lot construction.
25. Contractor to ensure that occupied homes be protected from erosion and sediment from the remainder
of the site.
26. Finalize grading activities.
27. Limit clearing and grubbing of the site to areas that will be mass graded. Whenever possible, existing
vegetation shall remain in place to prevent erosion of the site.
28. All areas that go unworked for 14 days or more must be stabilized immediately. Stabilization standards
shall be maintained throughout the construction process.
29. Maintain an adjust erosion and sediment control measures as grading and construction progresses.
30. The contractor shall diligently and continuously maintain all erosion control devices and structures.
31. Stabilize site as areas are brought to grade.
32. Coordinate with erosion control inspector prior to removal of erosion control measures. Upon inspector's
approval, contractor is to remove all erosion control measures, including any approved sediment basins.
33. Conversion of sediment basins to permanent stormwater basins to be completed per approved
construction plans. Bring areas outside of permanent stormwater basins, previously occupied by sediment
basins and associated grading to finished grade or where applicable back to the approximate existing
grade and replanted.
34. All erosion control measures shall be constructed in accordance with NCDEQ standards.
5

AMERICAN
Engineering
Skyland Drive Townhomes
Stormwater Calculations
American Engineering Associates -Southeast, PA.
8008 Corporate Center Drive, Suite 110
Charlotte, NC 28226
OFFICE: 704.375.2438
www.American-EA.com
35. When vegetation is established, call for final site inspection and file a notice of termination with the town
of Mt. Pleasant/NCDEQ.
lA

AMERICAN
Engineering
Skyland Drive Townhomes
Stormwater Calculations
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American Engineering Associates -Southeast, PA.
8008 Corporate Center Drive, Suite 110
Charlotte, NC 28226
OFFICE: 704.375.2438
www.American-EA.com
7

American Engineering Associates -Southeast, PA.
AM E RICAN 8008 Corporate Center Drive, Suite110
Charlotte, NC 28226226
E n g i n e e r i n g OFFICE: 704.375.2438
www.American-EA.com
Skyland Drive Townhomes
Stormwater Calculations
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AMERICAN
Engineering
Skyland Drive Townhomes
Stormwater Calculations
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American Engineering Associates -Southeast, PA.
8008 Corporate Center Drive, Suite 110
Charlotte, NC 28226
OFFICE: 704.375.2438
www.American-EA.com
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AMERICAN
Engineering
Skyland Drive Townhomes
Stormwater Calculations
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American Engineering Associates -Southeast, PA.
8008 Corporate Center Drive, Suite 110
Charlotte, NC 28226
OFFICE: 704.375.2438
www.American-EA.com
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10

AMERICAN
Engineering
Skyland Drive Townhomes
Stormwater Calculations
Description
American Engineering Associates -Southeast, PA.
8008 Corporate Center Drive, Suite 110
Charlotte, NC 28226
OFFICE: 704.375.2438
www.American-EA.com
Hydrologic soil groups are based on estimates of runoff potential. Soils are assigned to one of four groups
according to the rate of water infiltration when the soils are not protected by vegetation, are thoroughly wet, and
receive precipitation from long -duration storms.
The soils in the United States are assigned to four groups (A, B, C, and D) and three dual classes (A/D, B/D, and
C/D). The groups are defined as follows:
Group A. Soils having a high infiltration rate (low runoff potential) when thoroughly wet. These consist mainly of
deep, well drained to excessively drained sands or gravelly sands. These soils have a high rate of water
transmission.
Group B. Soils having a moderate infiltration rate when thoroughly wet. These consist chiefly of moderately deep
or deep, moderately well drained or well drained soils that have moderately fine texture to moderately coarse
texture. These soils have a moderate rate of water transmission.
Group C. Soils having a slow infiltration rate when thoroughly wet. These consist chiefly of soils having a layer that
impedes the downward movement of water or soils of moderately fine texture or fine texture. These soils have a
slow rate of water transmission.
Group D. Soils having a very slow infiltration rate (high runoff potential) when thoroughly wet. These consist
chiefly of clays that have a high shrink -swell potential, soils that have a high water table, soils that have a claypan
or clay layer at or near the surface, and soils that are shallow over nearly impervious material. These soils have a
very slow rate of water transmission.
If a soil is assigned to a dual hydrologic group (A/D, B/D, or C/D), the first letter is for drained areas and the
second is for undrained areas. Only the soils that in their natural condition are in group D are assigned to dual
classes.
Rating Options
Aggregation Method: Dominant Condition
Component Percent Cutoff.• None Specified
Tie -break Rule: Higher
11

AMERICAN
Engineering
Skyland Drive Townhomes
Stormwater Calculations
American Engineering Associates -Southeast, PA.
8008 Corporate Center Drive, Suite 110
Charlotte, NC 28226
OFFICE: 704.375.2438
www.American-EA.com
USGS Topographic Map
Portion of MT. PLEASANT QUADRANGLE — 7.5 Minute Series
12

AMERICAN
Engineering
Skyland Drive Townhomes
Stormwater Calculations
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American Engineering Associates -Southeast, PA.
8008 Corporate Center Drive, Suite 110
Charlotte, NC 28226
OFFICE: 704.375.2438
www.American-EA.com
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13

STORM DRAIN
CALCULATIONS

Hydraflow Storm Sewers Extension for Autodesk® AutoCAD® Civil 3D® Plan
A13
15 A14
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9
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6
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1
Outfall
Project File: Storm A.stm Number of lines: 15 Date: 10/7/2019
Storm Sewers 02.00

Storm Sewer Tabulation
Page 1
Station
Len
Drng Area
Rnoff
Area x C
Tc
Rain
Total
Cap
Vol
Pipe
Invert Elev
HGL Elev
Grnd / Rim Elev
Line ID
coeff
(1)
flow
full
Line
To
Incr
Total
Incr
Total
Inlet
Syst
Size
Slope
Dn
Up
Dn
Up
Dn
Up
Line
(ft)
(ac)
(ac)
(C)
(min)
(min)
(in/hr)
(cfs)
(cfs)
(ft/s)
(in)
M
(ft)
(ft)
(ft)
(ft)
(ft)
(ft)
1
End
41.646
0.00
1.74
0.00
0.00
1.40
0.0
11.3
5.8
8.08
7.80
5.44
18
0.55
666.09
666.32
667.19
667.59
667.88
678.59
All-Al2
2
1
37.250
0.10
1.74
0.80
0.08
1.40
5.0
11.2
5.8
8.11
7.50
4.59
18
0.51
666.32
666.51
667.93
668.16
678.59
677.58
All 0-A11
3
2
69.864
0.03
1.64
0.80
0.02
1.32
5.0
11.0
5.9
7.70
7.43
4.36
18
0.50
666.51
666.86
668.43
668.80
677.58
677.74
A9-Al0
4
3
26.500
0.23
1.61
0.80
0.18
1.29
5.0
10.9
5.9
7.58
7.36
4.29
18
0.49
666.86
666.99
669.00
669.14
677.74
677.74
A8-A9
5
4
114.489
0.22
1.24
0.80
0.18
0.98
5.0
10.4
6.0
5.86
7.41
3.31
18
0.50
666.99
667.56
669.42
669.78
677.74
675.21
A7-AB
6
5
52.208
0.07
0.89
0.80
0.06
0.70
5.0
10.1
6.0
4.23
7.55
2.39
18
0.52
667.56
667.83
669.93
670.01
675.21
674.15
A5-A7
7
6
26.500
0.06
0.45
0.80
0.05
0.36
5.0
8.2
6.4
2.31
4.52
1.95
15
0.49
668.86
668.99
670.08
670.11
674.15
674.24
A4-A5
8
7
52.208
0.21
0.39
0.80
0.17
0.31
5.0
7.7
6.5
2.04
4.56
1.88
15
0.50
668.99
669.25
670.16
670.19
674.24
676.14
A3-A4
9
8
26.500
0.06
0.18
0.80
0.05
0.14
5.0
7.2
6.7
0.96
6.52
3.39
15
1.02
670.98
671.25
671.30
671.63
676.14
676.14
A2-A3
10
9
74.014
0.12
0.12
0.80
0.10
0.10
5.0
5.0
7.2
0.69
6.46
2.45
15
1.00
671.25
671.99
671.63
672.32
676.14
676.96
Al-A2
11
5
31.371
0.13
0.13
0.80
0.10
0.10
5.0
5.0
7.2
0.75
6.42
3.15
15
0.99
670.97
671.28
671.26
671.62
675.21
675.16
A6-A7
12
4
102.750
0.14
0.14
0.90
0.13
0.13
5.0
5.0
7.2
0.91
6.89
3.42
15
1.14
669.50
670.67
669.81
671.04
677.74
679.09
A16-A8
13
6
89.065
0.14
0.37
0.80
0.11
0.29
5.0
8.8
6.3
1.80
7.38
1.02
18
0.49
667.83
668.27
670.08
670.11
674.15
671.89
All5-A5
14
13
32.853
0.13
0.23
0.80
0.10
0.17
5.0
8.0
6.5
1.12
7.33
0.64
18
0.49
668.27
668.43
670.13
670.13
671.89
671.89
A14-A15
15
14
51.916
0.10
0.10
0.70
0.07
0.07
5.0
5.0
7.2
0.51
23.50
1.36
18
5.01
668.47
671.07
670.13
671.33
671.89
672.86
A13-A14
Project File: Storm A.stm
Number of lines: 15
Run Date: 101712019
NOTES:Intensity = 88.24 / (Inlet time + 15.50) ^ 0.83; Return period =Yrs. 10 c = cir e = ellip b = box
Storm Sewers 02.00

Storm Sewer Profile
Proj. file: Storm A.stm
Elev. (ft)
687.00
682.00
677.00
672.00
667.00
662.00
0
N M �
co C J 0 C J 0 C J OC J OC
CO r— co M C)
LO
C 0 C J 0 C J O C J 0 C J O C C 0
.
.
.
.
.
.
.
■�■
.
■
milli
I■�■�■
■
■III■I■IIIIII
IIII■1■-IIIIII
IN■111111111■111111MA
�M1■
M.
50
HGL
687.00
682.00
677.00
672.00
1.00%
667.00
662.00
100 150 200 250 300 350 400 450 500 550
- EGL Reach (ft)
Storm Sewers

Storm Sewer Profile
Proj. file: Storm A.stm
Elev. (ft)
OE
CO I--
NU')M
o CO �
oWww
. E > >
cnSS
J O
CO
� �N
M �°CO
o Ww
m E
cn �_
684.00
684.00
681.00
678.00
681.00
678.00
675.00
675.00
672.00
--------
----------------
--
672.00
3
.3 -
669.00
669.00
0 10 20 30 40 50 60 70 80 90 100
HGL EGL Reach (ft)
Storm Sewers

Storm Sewer Profile
Proj. file: Storm A.stm
Elev. (ft)
685.00
681.00
O C
J
Q C
a
5
J Q C
2
E
J COO
'685.00
681.00
677.00
677.00
673.00
669.00
665.00
673.00
669.00
665.00
0 25 50 75
HGL EGL
100 125 150
Reach (ft)
175
■
�
I1
�Z1l:7Zft�
:n � . • � .
Storm Sewers

Storm Sewer Profile
Proj. file: Storm A.stm
Elev. (ft)
686.00
OS
Arno
� M
C?
o �° CO (D
+Lu
:° E > >
c75 of S S
N
73
O
rnr-
o�
� o
o (OCO
+ Ww
CO
cn of S
686.00
682.00
678.00
682.00
678.00
674.00
670.00
666.00
------------------------------------- -- -------------------------------------------- ---
u
0 10 20 30 40 50 60 70 80 90 100
HGL EGL Reach (ft)
674.00
670.00
666.00
110
Storm Sewers

Hydraflow Storm Sewers Extension for Autodesk® AutoCAD® Civil 3D® Plan
Outfall
1
B3
2
B2
3
B1
Project File: Storm B.stm Number of lines: 3 Date: 10/8/2019
Storm Sewers 02.00

Storm Sewer Tabulation
Page 1
Station
Len
Drng Area
Rnoff
Area x C
Tc
Rain
Total
Cap
Vol
Pipe
Invert Elev
HGL Elev
Grnd / Rim Elev
Line ID
coeff
(1)
flow
full
Line
To
Incr
Total
Incr
Total
Inlet
Syst
Size
Slope
Dn
Up
Dn
Up
Dn
Up
Line
(ft)
(ac)
(ac)
(C)
(min)
(min)
(in/hr)
(cfs)
(cfs)
(ft/s)
(in)
M
(ft)
(ft)
(ft)
(ft)
(ft)
(ft)
1
End
40.118
0.00
0.54
0.00
0.00
0.33
0.0
5.2
7.2
2.34
21.00
3.72
18
4.00
666.20
667.80
666.78
668.38
668.00
669.61
133-134
2
1
6.564
0.00
0.54
0.00
0.00
0.33
0.0
5.2
7.2
2.35
21.00
3.72
18
4.00
667.80
668.06
668.38
668.64
669.61
672.82
132-133
3
2
12.875
0.54
0.54
0.60
0.33
0.33
5.0
5.0
7.2
2.36
23.48
6.12
18
5.00
669.02
669.66
669.34
670.24
672.82
671.45
131-132
Project File: Storm B.stm
Number of lines: 3
Run Date: 101812019
NOTES:Intensity = 88.24 / (Inlet time + 15.50) ^ 0.83; Return period =Yrs. 10 ; c = cir e = ellip b = box
Storm Sewers 02.00

GUTTER SPREAD
CALCULATIONS

GUTTER SPREAD CALCULATIONS
PROJECT: Skyland Drive Townhomes COMPUTED BY: BMF
LOCATION: Charlotte, NC
RAINFALL INTENSITY = 4.0 in/hr (On Grade Conditions - Roadway)
RAINFALL INTENSITY = 8.21 in/hr (Sag Conditions - Roadway 25 year)
CHECKED BY: BMF
DATE: 10/4/2019
Trib.
C
Sag
St
SI
Single/Double
Struct. Number
Area
Factor
Condition
Cul-de-sac
Flow
Cross Slope
Long. Slope
Grate
T
D
K
Qcap
Qbypass
Contributing Structures / Flow
Qadd
(ac)
(Y/N)
(Y/N)
(cfs)
(ft/ft)
(ft/ft)
(S/D)
(ft)
(in)
(cfs)
(cfs)
(cfs)
(cfs)
Al
0.12
0.80
Y
N
0.79
0.02000
---
S
5.29
0.11
0.00
A2
0.06
0.80
N
N
0.19
0.02000
0.0260
S
3.25
0.06
24.85
0.26
0.00
0.00
A3
0.21
0.80
N
N
0.67
0.02000
0.0260
S
5.19
0.10
24.85
0.57
0.10
0.00
A4
0.06
0.80
N
N
0.29
0.02000
0.0340
S
3.62
0.07
26.85
0.34
0.00
0)
0.10
(0
A5
0.07
0.80
N
N
0.45
0.02000
0.0340
S
4.24
0.08
26.85
0.44
0.01
0.22
(0 22)
A6
0.13
0.80
Y
N
0.85
0.02000
---
S
5.58
0.11
A2
A9
0.00
(0.00)
(0.00)
A7
0.22
0.80
N
N
0.86
0.02000
0.0060
S
7.48
0.15
14.98
0.63
0.22
5)
0.15
(0
A8
0.24
0.80
N
N
0.77
0.02000
0.0300
S
5.31
0.11
25.85
0.62
0.15
0.00
A9
0.03
0.80
N
N
0.10
0.02000
0.0300
S
2.44
0.05
25.85
0.17
0.00
0.00
A10
0.10
0.80
N
N
0.32
0.02000
0.0300
S
3.83
0.08
25.85
0.36
0.00
0.00
A14
0.13
0.80
Y
N
0.85
0.02000
---
S
5.58
0.11
4
0.00
00)
(0
A15
0.14
0.80
Y
N
0.93
0.02000
---
S
5.90
0.12
5
0.01
01)
(0
B2
0.21
0.80
Y
N
1.38
0.02000
---
S
7.68
0.15
0.00
(0.00)
B3
0.15
0.80
Y
N
0.99
0.02000
---
S
6.17
0.12
0.01
(0 0 )
0.00
0.00
0.00
0.00
Pagel of 2

TIME OF CONCENTRATION
CALCULATIONS

� R%,
INV.666.2
_ R/W� (PARTIALLY O Bus
_ — BURIED) �N ✓ SHELTER
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___OE-� __ / — — R/W -
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—OE--/db PP OE — —OE— —OE— — INV. �667.2 �� R
OE--OE--OE--OE
— — �, EDGE OF PAVEME — — _ ; ; (60' PUBLIC R/W -MAINTAINED) — — W — — — — — — — — „ b —
\—w--w--w--w--w--w--w— --w— w-- — —--w--w—;;mow--w--w--W--W--W--W— W--'W
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\ \ R \ \ \ � j �\ \ \ \ � --0.1955 acres
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TRACT 1 AND PART OF TRACT 2 x \ \ \ \ \
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-_ I �9.
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NOW OR FORMERLY
TERRY R TUCKER &
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DR 12430, PG 43
PIN: 5EE0-95-53.92
TRACT 1
MR 72, PG 107
3435 HIGHWAY 73 E
CONCORD NC 28025
ZONED "RFJ"
She Flow
L=63
S = 9.50,0
n = 0.24
Shallow Conce
L=45'
S = 4.4%
Wooded
/, Woo PRO,�� m F ---
�'`.�' ON
�� r ✓ , f NOW OR FORMERLY
x �� 1 III III 1I I GF DA SHOES
`~ d✓ ✓ �✓ �� ��d� / / 330
EXISTING POND OR 545r -95PG. 714
I } PIN: LOTS
395-7144
r���� / LOTS 35-40
s R b, F'Cx 63
d + MT: PLEASANT; NC28124
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x x x� x R/W — — R —pE R�`n/ — —
CONCRETE "E OE x _
OE �E -
-__ / X X X X X X x X j JpP 0—OE--OET—OE— —OE— — E— PP DRIVE
/ � � O � � �� � �� X
� ABBOTT STREET �. �,
IAN PUBLIC R/W)
\ (PB 8/63, DB 350/510)
\ R/W — — R/W — — R/W — — R/W — — R/W — — R/W — — R/W
GRAPHIC SCALE
30 0 15 30 60
( IN FEET)
finch =30ft.
4Z8.cL R/W —
u 011— u— — ou
— ou—
gDGE OF PA VEMFNT
--W
EDGE OF PAVEMENT 1
�V.669.112
Lu
OE�
LP TANK
- R/W — —
on i r
Flow
W. FranklinV
LOCATION MAP
NOT TO SCALE
LEGEND
- - - —> TIME OF CONCENTRATION FLOW LINE
EnB ENON SANDY LOAM - GROUP C
EnD ENON SANDY LOAM - GROUP C
PRE-DEV POA-1
TOTAL AREA = 4.406 AC
CN 70
Tc=7.4min.
Pre Development CN (Onsite)
COVERAGE AND CN VALUES
LAND
USE
AREA
(ac)
GROUP
CN
AREA x CN
B
(ac/CN)
C
(ac/CN)
D
(ac/CN)
IMPERV.
0.000
0.00
0.00
0.00
0
0.00
98
98
98
WOODS*
2.203
0.00
2.20
0.00
70
154.21
55
70
77
BRUSH**
2.203
0.00
2.20
0.00
70
154.21
56
70
77
TOTAL
4.406
70
308.42
*** 3 Days Before Digging ***
North Carolina 811
811 or1-800-632-4949
Remote Ticket Entry
http://nc8l l.org/remoteticketentry.hbn
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```III\11111111/,,,,
SS/ /
33046
STIPULATION FOR REUSE
THIS DRAWING WAS PREPARED FOR USE
ON A SPECIFIC SITE, SKYLAND DRIVE
TOWNHOMES, S. SKYLAND DRIVE, MT.
PLEASANT, NC, CONTEMPORANEOUSLY
WITH ITS ISSUE DATE ON 4/12/19. AND
IT IS NOT SUITABLE FOR USE ON A
DIFFERENT PROJECT SITE OR AT A LATER
TIME. USE OF THIS DRAWING FOR
REFERENCE OR EXAMPLE ON ANOTHER
PROJECT REQUIRES THE SERVICES OF
PROPERLY LICENSED ARCHITECTS AND
ENGINEERS. REPRODUCTION OF THIS
DRAWING FOR REUSE ON ANOTHER
PROJECT IS NOT AUTHORIZED AND MAY
BE CONTRARY TO THE LAW.
V 1
W
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MODIFICATION LOG
JOB NUMBER: C190010
CHECKED BY: BMF
DRAWN BY: BHE
DATE: 4-12-2019
689E-0 # W2i1=1
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DRAINAGE
MAP
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/111111111IIIII

\ Raw
INV:666.2
R/W (PARTIALLY Bus
BURIED) p�D� / SHEL TER
- - _ R/W - - R - - R/W - - R/W - - R/� R/W� - R/W - - R/W - - R/W -
pp
- - - -OE- -OE- OF -O--OE- OE - OE - OE$r--OE- -OE- _R/W_
- _
OE �E OE- OE OF �-GE DOE OE OE OE OE OE OE R/W
pp - OE - -OE- - -OE- INV: -6672 �- !zw 2 R/W
\ EDGE OF PA VEME OE - - OE - - OE - - - - - -
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-W--W-- �L
EDG OF PAVEMENT / SSKYL ND DRIVE(S.R.2657 !! - - - _ _ - - _ - w--w--wl,a w w__+w GE OF PAVEMN w w
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I
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_ _ V: 6159, 82
--R/W,- R/W R/ R/W - - - - �OE� B€-- �_ -0E - - Or�o
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\ \ \ \
m \
0
un
NOW OR FORMERLY
JOHNNIE F SULLIVAN
DB 7447, PG 58
PIN:5660-94-0591
TRACT 1 AND PART OF TRACT 2
MB 35, PG 33
997. SKYLAND DR.
MT. PLEASANT, NC 28124
ZONED "RL"
\
1
2
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NOW OR FORMERLY
GEORGE A SHOE &
\ / / FREDAE
EXISTING POND ` \ \ I IDB 545, PG.
33
PIN. 5660-95 7144
LOTS 35-40
MB 8, PG 63
1010 ABBOTT ST.
/ I MT. PLEASANT, NC 28124
ZONED "RH"
/ + + -R/W-- - bE _ R4V -
/ I I �
/ X X X X X �X x �x x x /PP 0 -OE--OE,T-OE--OE--
E- �OE
/ABBOTT STREE / o
(40' PUBLIC R/W)
/ (PB 8/63, DB 350/510) /
FM FM
M / CFI 1� FM
R/W - R/W - - R/NY R/W - - R/W �T rv/ vv /�/ /
�C
� o
OE T'
PP -�-IOE - _ OE
WLu 3
I�m00
a O
Q
W
S
GRAPHIC SCALE
30 0 15 30 60
( IN FEET)
1 inch = 30 ft.
W. Franklin Street
LOCATION MAP
NOT TO SCALE
LEGEND
- - - -> TIME OF CONCENTRATION FLOW LINE
En B ENON SANDY LOAM - GROUP C
En D ENON SANDY LOAM - GROUP C
POST-DEV POA-1
TOTAL AREA
4.405 AC
DETAINED AREA
IMPERVIOUS:
1.335 AC
PERVIOUS:
0.906 AC
TOTAL:
2.241 AC CN = 87
TIC =5.0MIN
UNDETAINED AREA
IMPERVIOUS:
0.232 AC
PERVIOUS:
1.932 AC
TOTAL:
2.164 AC CN = 70
TIC =10.0 MIN
Post Development Undetained CN
COVERAGE AND CN VALUES
LAND
USE
AREA
(ac)
GROUP
CN
AREA x CN
B
(ac/CN)
C
(ac/CN)
D
(ac/CN)
IMPERV.
0.232
0.00
0.23
0.00
98
22.74
98
98
98
OPEN
1.302
0.00
1.30
0.00
74
96.35
r
61
74
80
WOODS
0.63
0.00
0.63
0.00
70
44.10
55
1 70
77
TOTAL
2,164
75
163.18
Post Development Detained CN
COVERAGE AND CN VALUES
LAN D
USE
AREA
(ac)
GROUP
CN
AREA x CN
B
(ac/CN)
C
(ac/CN)
D
(ac/CN)
IMPERV.
1.335
0.00
1.34
0.00
98
130.83
98
98
98
OPEN
0.906
0.00
0.91
0.00
74
67.04
61
74
80
WOODS
0
0.00
0.00
0.00
0
0.00
55
70
77
TOTAL
2.241
88
1197.87
2
*** 3 Days Before Digging
0-07-19
North Carolina 811
811 or 1-800-632-4949
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STIPULATION FOR REUSE
THIS DRAWING WAS PREPARED FOR USE
ON A SPECIFIC SITE, SKYLAND DRIVE
TOWNHOMESI S. SKYLAND DRIVE, MT.
PLEASANT, NC, CONTEMPORANEOUSLY
WITH ITS ISSUE DATE ON 10/07/19. AND
IT IS NOT SUITABLE FOR USE ON A
DIFFERENT PROJECT SITE OR AT A LATER
TIME. USE OF THIS DRAWING FOR
REFERENCE OR EXAMPLE ON ANOTHER
PROJECT REQUIRES THE SERVICES OF
PROPERLY LICENSED ARCHITECTS AND
ENGINEERS. REPRODUCTION OF THIS
DRAWING FOR REUSE ON ANOTHER
PROJECT IS NOT AUTHORIZED AND MAY
BE CONTRARY TO THE LAW.
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MODIFICATION LOG
JOB NUMBER: C190010
CHECKED BY: BMF
DRAWN BY: BHE
DATE: 10-07-2019
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POST
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DRAINAGE
MAP
SHEET:
MIMMM

SAND FILTER CALCULATIONS

STORM
WATER
4.8.7 Design Procedure Form
Design Procedure Form: Sand Filter
BIORETENTION FEASIBILITY
NOTES:
1 Is the use of a sand filter appropriate?
2 Confirm other design criteria and applicability.
Pollutant Removal Effectiveness Required
Optimal
PRELIMINARY HYDROLOGIC CALCULATIONS
3 Compute site hydrologic input parameters
Development Conditions
Pre -developed
Post -developed
Area
4.405 acres
2.25 acres
CN (SCS curve number)
70
88
Adjusted CN (curve number adjusted for 1-inch storm)
94.98
Time of concentration
7.4 min
5 min
0.12 hours
0.08 hours
4 Compute,WQv water quality volume requirements
Compute Runoff Coefficient, Rv
Rv =
0.56
Compute WQv Volume requirements
WQV =
0.11 acre-ft
5
Compute WQp peak flow using SCS
WQP =
cfs
Compute modified SCS curve number
CN =
95.0
6
Compute CPv
Compute S (maximum retention)
S =
1.36
Compute 1-yr, 24-hrtotal rainfall depth
Rainfall Depth =
2.58 inches
Compute Qd (runoff volume)
Qd =
1.45 inches
Compute CPv (chnnnel protection volume)
CPV =
0.27 acre-ft
7
Size Flow Diversion Structure
8
Compute release rates
Compute WQv release rate
Release Rate =
0.025 cfs
Compute CPv release rate
Release Rate =
0.055 cfs
SAND FILTER DESIGN
9
Compute sediment chamber volume
Volpfe =
0.021 acre-ft
Volpfe = (0.20)(WQv)
10
Average height of water above filter bed
hf =
1_0 ft
Determine Area of Sand ponding/filter area
Af=
440.8 ft2
11
Set design eleveations and dimensions of facility
Length =
42 ft
Width =
12.0000 ft
Top Elevation =
666 ft
12
Develop stage -discharge and sta a stora e
Elevation
Area (ft)
Volume Acc. Vol
Q
(ft) ft3
(cfs)
666
2,385
0
0
667
2,881
2,629
0.03
668
3,404
5,768
0.26
669
3,956,
9,445,
0.37
670
4,5361
13,6871
0.45
671
5,3281
1 18,6141
13.62

STORM
WATER
13 Route flows through bioretention area. Resize the footprint
area, if desired. Step is most effective for facilities with flow
diverters. Ensure detention time requirements and
maximum ponding depth requirements are met.
14 Design conveyance to facility
15 Size underdrain system Length = 90 ft
16 Design emergency overflow Length of Weir (if used)
17 Prepare vegetation and landscaping plan

Sand Filter Underdrain System Calculations
Project Name: Skyland Dr Townhomes
Project Number: C190010
Designed By: BMF Date: 3/26/2019
Checked By: BMF Date: 3/26/2019
Number of Pipes
2
Pipe Length
40 ft
Pipe Slope
0.005 ft/ft
Pipe Diameter
6 in
Perforation Diameter
0.375 in
WQv
0.028 cfs
Number of Perforations
1216 holes
50% Perforations
608 holes
Capacity of one hole
0.0083 cfs
Total Capacity
5.018 cfs
Capacity of Pipe
0.513 cfs
50% Assuming Clogging
0.257 cfs
Design Discharge Rate
for the Sand Filter: 0.028 cfs (from BMP sizing)

Calculate the Sand Filter discharge rate:
Qo = Af (k)(hf+df)/(df))
Where: Af = surface area of filter bed (ft2)
df = filter bed depth (ft), length of flow
k = coefficient of permeability of filter media (ft/day)
hf = average height of water above filter bed (ft), change in pressure head
Sand Filter No.:
Sand Filter Area (Af):
k:
Sand Filter Depth (df):
1
504 sf
3.5 ft/day per ft depth
2.5 ft
Stage (hf)
Elev
Discharge
(ft)
(ft)
(cfs)
0
667
0
1
668
0.029
2
669
0.037
3
670
0.045
4
671
0.053
5
672
0.061
6
673
0.069

Pre -Development
Subcat Reach on Link
Post-
ined Post-Un Jetained
47
2A �
Sand Filter
Post Total

Skyland Drive Townhomes_Sand Filter Charlotte 6-hr 100-yr Rainfall=5.34"
Prepared by {enter your company name here} Printed 4/2/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC
Events for Subcatchment 1: PRE
Event
Rainfall
(inches)
Runoff
(cfs)
Volume
(cubic -feet)
Depth
(inches)
1-inch
1.00
0.01
74
0.00
2-yr
2.28
2.64
5,671
0.35
10-yr
3.72
9.22
18,333
1.15
25-yr
4.38
12.79
25,414
1.59
50-yr
4.92
15.73
31,616
1.98
100-yr
5.34
18.57
36,647
2.29

27
Post-D
ined
Post-Undetained
Sand Filter Post Total
S4
Reach on Link

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 2
Area Listing (all nodes)
Area CN Description
(sq-ft) (s u bcatch me nt- n u m be rs)
86,859 88 Post -Development Detained Areas (2)
93,698 70 Post -Development Undetained Areas (3)
11,326 98 Roofs, HSG B (2)
191,882 80 TOTAL AREA

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-1 Charlotte 6-hr 1-inch Rainfall=1.00"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 3
Time span=0.00-120.00 hrs, dt=0.02 hrs, 6001 points
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN
Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method
Subcatchment 2: Post -Detained Runoff Area=2.254 ac Runoff Depth=0.28"
Tc=5.0 min CN=89 Runoff=1.47 cfs 2,332 cf
Subcatchment 3: Post-Undetained Runoff Area=2.151 ac Runoff Depth=0.00"
Tc=10.0 min CN=70 Runoff=0.01 cfs 36 cf
Pond 2A: Sand Filter Peak Elev=666.86' Storage=2,224 cf Inflow=1.47 cfs 2,332 cf
Outflow=0.01 cfs 2,114 cf
Link 4: Post Total Inflow=0.02 cfs 2,150 cf
Primary=0.02 cfs 2,150 cf
Total Runoff Area = 191,882 sf Runoff Volume = 2,368 cf Average Runoff Depth = 0.15"

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-1 Charlotte 6-hr 1-inch Rainfall=1.00"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 4
Summary for Subcatchment 2: Post -Detained
Runoff = 1.47 cfs @ 3.17 hrs, Volume= 2,332 cf, Depth= 0.28"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 1-inch Rainfall=1.00"
Area (ac) CN Description
1.624 88 Post -Development Detained Areas
0.370 88 Post -Development Detained Areas
0.260 98 Roofs. HSG B
2.254 89 Weighted Average
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry, Post -Detained
❑ Runoff

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-1 Charlotte 6-hr 1-inch Rainfall=1.00"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 5
Hydrograph for Subcatchment 2: Post -Detained
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
0.00
0.00
0.00
0.00
2.00
0.11
0.00
0.00
4.00
0.88
0.22
0.14
6.00
1.00
0.28
0.05
8.00
1.00
0.28
0.00
10.00
1.00
0.28
0.00
12.00
1.00
0.28
0.00
14.00
1.00
0.28
0.00
16.00
1.00
0.28
0.00
18.00
1.00
0.28
0.00
20.00
1.00
0.28
0.00
22.00
1.00
0.28
0.00
24.00
1.00
0.28
0.00
26.00
1.00
0.28
0.00
28.00
1.00
0.28
0.00
30.00
1.00
0.28
0.00
32.00
1.00
0.28
0.00
34.00
1.00
0.28
0.00
36.00
1.00
0.28
0.00
38.00
1.00
0.28
0.00
40.00
1.00
0.28
0.00
42.00
1.00
0.28
0.00
44.00
1.00
0.28
0.00
46.00
1.00
0.28
0.00
48.00
1.00
0.28
0.00
50.00
1.00
0.28
0.00
52.00
1.00
0.28
0.00
54.00
1.00
0.28
0.00
56.00
1.00
0.28
0.00
58.00
1.00
0.28
0.00
60.00
1.00
0.28
0.00
62.00
1.00
0.28
0.00
64.00
1.00
0.28
0.00
66.00
1.00
0.28
0.00
68.00
1.00
0.28
0.00
70.00
1.00
0.28
0.00
72.00
1.00
0.28
0.00
74.00
1.00
0.28
0.00
76.00
1.00
0.28
0.00
78.00
1.00
0.28
0.00
80.00
1.00
0.28
0.00
82.00
1.00
0.28
0.00
84.00
1.00
0.28
0.00
86.00
1.00
0.28
0.00
88.00
1.00
0.28
0.00
90.00
1.00
0.28
0.00
92.00
1.00
0.28
0.00
94.00
1.00
0.28
0.00
96.00
1.00
0.28
0.00
98.00
1.00
0.28
0.00
100.00
1.00
0.28
0.00
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
102.00
1.00
0.28
0.00
104.00
1.00
0.28
0.00
106.00
1.00
0.28
0.00
108.00
1.00
0.28
0.00
110.00
1.00
0.28
0.00
112.00
1.00
0.28
0.00
114.00
1.00
0.28
0.00
116.00
1.00
0.28
0.00
118.00
1.00
0.28
0.00
120.00
1.00
0.28
0.00

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-1 Charlotte 6-hr 1-inch Rainfall=1.00"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 6
Summary for Subcatchment 3: Post-Undetained
Runoff = 0.01 cfs @ 5.66 hrs, Volume= 36 cf, Depth= 0.00"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 1-inch Rainfall=1.00"
Area (ac) CN Description
2.151 70 Post -Development Undetained Areas
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
10.0 Direct Entry, Post-Undetained
■ Runoff
N
U
3
0
LL

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-1 Charlotte 6-hr 1-inch Rainfall=1.00"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 7
Hydrograph for Subcatchment 3: Post-Undetained
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
0.00
0.00
0.00
0.00
2.00
0.11
0.00
0.00
4.00
0.88
0.00
0.00
6.00
1.00
0.00
0.00
8.00
1.00
0.00
0.00
10.00
1.00
0.00
0.00
12.00
1.00
0.00
0.00
14.00
1.00
0.00
0.00
16.00
1.00
0.00
0.00
18.00
1.00
0.00
0.00
20.00
1.00
0.00
0.00
22.00
1.00
0.00
0.00
24.00
1.00
0.00
0.00
26.00
1.00
0.00
0.00
28.00
1.00
0.00
0.00
30.00
1.00
0.00
0.00
32.00
1.00
0.00
0.00
34.00
1.00
0.00
0.00
36.00
1.00
0.00
0.00
38.00
1.00
0.00
0.00
40.00
1.00
0.00
0.00
42.00
1.00
0.00
0.00
44.00
1.00
0.00
0.00
46.00
1.00
0.00
0.00
48.00
1.00
0.00
0.00
50.00
1.00
0.00
0.00
52.00
1.00
0.00
0.00
54.00
1.00
0.00
0.00
56.00
1.00
0.00
0.00
58.00
1.00
0.00
0.00
60.00
1.00
0.00
0.00
62.00
1.00
0.00
0.00
64.00
1.00
0.00
0.00
66.00
1.00
0.00
0.00
68.00
1.00
0.00
0.00
70.00
1.00
0.00
0.00
72.00
1.00
0.00
0.00
74.00
1.00
0.00
0.00
76.00
1.00
0.00
0.00
78.00
1.00
0.00
0.00
80.00
1.00
0.00
0.00
82.00
1.00
0.00
0.00
84.00
1.00
0.00
0.00
86.00
1.00
0.00
0.00
88.00
1.00
0.00
0.00
90.00
1.00
0.00
0.00
92.00
1.00
0.00
0.00
94.00
1.00
0.00
0.00
96.00
1.00
0.00
0.00
98.00
1.00
0.00
0.00
100.00
1.00
0.00
0.00
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
102.00
1.00
0.00
0.00
104.00
1.00
0.00
0.00
106.00
1.00
0.00
0.00
108.00
1.00
0.00
0.00
110.00
1.00
0.00
0.00
112.00
1.00
0.00
0.00
114.00
1.00
0.00
0.00
116.00
1.00
0.00
0.00
118.00
1.00
0.00
0.00
120.00
1.00
0.00
0.00

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-1 Charlotte 6-hr 1-inch Rainfall=1.00"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 8
Summary for Pond 2A: Sand Filter
Inflow Area = 98,184 sf, Inflow Depth = 0.28" for 1-inch event
Inflow = 1.47 cfs @ 3.17 hrs, Volume= 2,332 cf
Outflow = 0.01 cfs @ 6.10 hrs, Volume= 2,114 cf, Atten= 99%, Lag= 175.9 min
Primary = 0.01 cfs @ 6.10 hrs, Volume= 2,114 cf
Routing by Stor-Ind method, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Peak Elev= 666.86' @ 6.10 hrs Surf.Area= 2,807 sf Storage= 2,224 cf
Plug -Flow detention time= 2,275.6 min calculated for 2,114 cf (91 % of inflow)
Center -of -Mass det. time= 2,264.4 min ( 2,487.8 - 223.4 )
Volume Invert
Avail.Storage Storage Description
#1 666.00'
34,734 cf Sand Filter (Conic) Listed below (Recalc)
Elevation Surf.Area
Inc.Store Cum.Store
Wet.Area
(feet)
(sq-ft)
(cubic -feet) (cubic -feet)
(sq-ft)
666.00
2,385
0 0
2,385
667.00
2,881
2,629 2,629
2,913
668.00
3,404
3,139 5,768
3,473
669.00
3,956
3,677 9,445
4,065
670.00
4,536
4,243 13,687
4,689
671.00
5,328
4,927 18,614
5,519
672.00
6,203
5,760 24,374
6,435
673.00
7,142
6,667 31,041
7,417
673.50
7,635
3,694 34,734
7,933
Device Routing
Invert
Outlet Devices
#1 Primary
666.00'
Sand Filter
Elev. (feet) 666.00 667.00 668.00
669.00 670.00 671.00 672.00
673.00
Disch. (cfs) 0.000 0.014 0.029 0.037 0.045 0.053 0.061 0.069
#2 Primary
666.90'
3.0" Vert. CP-Bleeder C= 0.600
#3 Primary
670.25'
48.0" x 48.0" Horiz. Orifice/Grate
C= 0.600
Limited to weir flow at low heads
#4 Device 3
662.47'
24.0" Round Culvert
L= 93.8' RCP, square edge headwall, Ke= 0.500
Inlet / Outlet Invert= 662.47' / 662.00' S= 0.0050 '/' Cc= 0.900
n= 0.013, Flow Area= 3.14 sf
Primary OutFlow Max=0.01 cfs @ 6.10 hrs HW=666.86' (Free Discharge)
1=Sand Filter (Custom Controls 0.01 cfs)
2=CP-Bleeder ( Controls 0.00 cfs)
3=Orifice/Grate ( Controls 0.00 cfs)
L4=Culvert ( Controls 0.00 cfs)

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-1 Charlotte 6-hr 1-inch Rainfall=1.00"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 9
Inflow
❑ Primary

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-1 Charlotte 6-hr 1-inch Rainfall=1.00"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 10
Hydrograph for Pond 2A: Sand Filter
Time
Inflow
Storage
Elevation
Primary
(hours)
(cfs)
(cubic -feet)
(feet)
(cfs)
0.00
0.00
0
666.00
0.00
4.00
0.14
1,698
666.67
0.01
8.00
0.00
2,145
666.83
0.01
12.00
0.00
1,983
666.77
0.01
16.00
0.00
1,833
666.72
0.01
20.00
0.00
1,694
666.67
0.01
24.00
0.00
1,565
666.62
0.01
28.00
0.00
1,445
666.57
0.01
32.00
0.00
1,334
666.53
0.01
36.00
0.00
1,231
666.49
0.01
40.00
0.00
1,135
666.46
0.01
44.00
0.00
1,047
666.42
0.01
48.00
0.00
965
666.39
0.01
52.00
0.00
890
666.36
0.01
56.00
0.00
820
666.33
0.00
60.00
0.00
756
666.31
0.00
64.00
0.00
696
666.28
0.00
68.00
0.00
641
666.26
0.00
72.00
0.00
590
666.24
0.00
76.00
0.00
544
666.22
0.00
80.00
0.00
500
666.21
0.00
84.00
0.00
461
666.19
0.00
88.00
0.00
424
666.17
0.00
92.00
0.00
390
666.16
0.00
96.00
0.00
359
666.15
0.00
100.00
0.00
330
666.14
0.00
104.00
0.00
304
666.13
0.00
108.00
0.00
280
666.12
0.00
112.00
0.00
257
666.11
0.00
116.00
0.00
237
666.10
0.00
120.00
0.00
218
666.09
0.00

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-1 Charlotte 6-hr 1-inch Rainfall=1.00"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 11
Elevation Primary
(feet)
(cfs)
666.00
0.00
666.04
0.00
666.08
0.00
666.12
0.00
666.16
0.00
666.20
0.00
666.24
0.00
666.28
0.00
666.32
0.00
666.36
0.01
666.40
0.01
666.44
0.01
666.48
0.01
666.52
0.01
666.56
0.01
666.60
0.01
666.64
0.01
666.68
0.01
666.72
0.01
666.76
0.01
666.80
0.01
666.84
0.01
666.88
0.01
666.92
0.01
666.96
0.02
667.00
0.03
667.04
0.05
667.08
0.07
667.12
0.09
667.16
0.10
667.20
0.12
667.24
0.13
667.28
0.14
667.32
0.15
667.36
0.16
667.40
0.16
667.44
0.17
667.48
0.18
667.52
0.19
667.56
0.20
667.60
0.20
667.64
0.21
667.68
0.22
667.72
0.22
667.76
0.23
667.80
0.23
667.84
0.24
667.88
0.25
667.92
0.25
667.96
0.26
668.00
0.26
Stage -Discharge for Pond 2A: Sand Filter
Elevation Primary
(feet)
(cfs)
668.04
0.27
668.08
0.27
668.12
0.28
668.16
0.28
668.20
0.29
668.24
0.29
668.28
0.30
668.32
0.30
668.36
0.30
668.40
0.31
668.44
0.31
668.48
0.32
668.52
0.32
668.56
0.33
668.60
0.33
668.64
0.33
668.68
0.34
668.72
0.34
668.76
0.35
668.80
0.35
668.84
0.35
668.88
0.36
668.92
0.36
668.96
0.37
669.00
0.37
669.04
0.37
669.08
0.38
669.12
0.38
669.16
0.38
669.20
0.39
669.24
0.39
669.28
0.39
669.32
0.40
669.36
0.40
669.40
0.40
669.44
0.41
669.48
0.41
669.52
0.41
669.56
0.42
669.60
0.42
669.64
0.42
669.68
0.43
669.72
0.43
669.76
0.43
669.80
0.44
669.84
0.44
669.88
0.44
669.92
0.45
669.96
0.45
670.00
0.45
670.04
0.46
Elevation Primary
(feet)
(cfs)
670.08
0.46
670.12
0.46
670.16
0.46
670.20
0.47
670.24
0.47
670.28
0.75
670.32
1.45
670.36
2.39
670.40
3.52
670.44
4.82
670.48
6.26
670.52
7.83
670.56
8.92
670.60
9.45
670.64
9.95
670.68
10.42
670.72
10.88
670.76
11.31
670.80
11.73
670.84
12.13
670.88
12.52
670.92
12.90
670.96
13.27
671.00
13.62
671.04
13.97
671.08
14.31
671.12
14.64
671.16
14.96
671.20
15.28
671.24
15.59
671.28
15.89
671.32
16.19
671.36
16.48
671.40
16.77
671.44
17.05
671.48
17.33
671.52
17.61
671.56
17.87
671.60
18.14
671.64
18.40
671.68
18.66
671.72
18.91
671.76
19.16
671.80
19.41
671.84
19.65
671.88
19.89
671.92
20.13
671.96
20.37
672.00
20.60
672.04
20.83
672.08
21.06
Elevation Primary
(feet)
(cfs)
672.12
21.28
672.16
21.50
672.20
21.72
672.24
21.94
672.28
22.16
672.32
22.37
672.36
22.58
672.40
22.79
672.44
23.00
672.48
23.21
672.52
23.41
672.56
23.61
672.60
23.81
672.64
24.01
672.68
24.21
672.72
24.40
672.76
24.60
672.80
24.79
672.84
24.98
672.88
25.17
672.92
25.36
672.96
25.55
673.00
25.73
673.04
25.92
673.08
26.10
673.12
26.28
673.16
26.46
673.20
26.64
673.24
26.82
673.28
26.99
673.32
27.17
673.36
27.34
673.40
27.52
673.44
27.69
673.48
27.86

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-1 Charlotte 6-hr 1-inch Rainfall=1.00"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 12
Stage -Area -Storage for Pond 2A: Sand Filter
Elevation
Surface
Storage
(feet)
(sq-ft)
(cubic -feet)
666.00
2,385
0
666.10
2,432
241
666.20
2,480
487
666.30
2,529
737
666.40
2,578
992
666.50
2,627
1,253
666.60
2,677
1,518
666.70
2,727
1,788
666.80
2,778
2,063
666.90
2,829
2,344
667.00
2,881
2,629
667.10
2,931
2,920
667.20
2,982
3,215
667.30
3,033
3,516
667.40
3,085
3,822
667.50
3,137
4,133
667.60
3,190
4,449
667.70
3,243
4,771
667.80
3,296
5,098
667.90
3,350
5,430
668.00
3,404
5,768
668.10
3,457
6,111
668.20
3,511
6,459
668.30
3,565
6,813
668.40
3,620
7,173
668.50
3,675
7,537
668.60
3,730
7,907
668.70
3,786
8,283
668.80
3,842
8,665
668.90
3,899
9,052
669.00
3,956
9,445
669.10
4,012
9,843
669.20
4,069
10,247
669.30
4,126
10,657
669.40
4,183
11,072
669.50
4,241
11,493
669.60
4,299
11,920
669.70
4,358
12,353
669.80
4,417
12,792
669.90
4,476
13,237
670.00
4,536
13,687
670.10
4,612
14,145
670.20
4,689
14,610
670.30
4,767
15,082
670.40
4,845
15,563
670.50
4,924
16,052
670.60
5,004
16,548
670.70
5,084
17,052
670.80
5,165
17,565
670.90
5,246
18,085
671.00
5,328
18,614
Elevation
Surface
Storage
(feet)
(sq-ft)
(cubic -feet)
671.10
5,413
19,151
671.20
5,498
19,696
671.30
5,584
20,250
671.40
5,670
20,813
671.50
5,757
21,385
671.60
5,845
21,965
671.70
5,934
22,554
671.80
6,023
23,151
671.90
6,113
23,758
672.00
6,203
24,374
672.10
6,294
24,999
672.20
6,386
25,633
672.30
6,478
26,276
672.40
6,571
26,928
672.50
6,664
27,590
672.60
6,758
28,261
672.70
6,853
28,942
672.80
6,949
29,632
672.90
7,045
30,331
673.00
7,142
31,041
673.10
7,239
31,760
673.20
7,337
32,489
673.30
7,436
33,227
673.40
7,535
33,976
673.50
7,635
34,734

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-1 Charlotte 6-hr 1-inch Rainfall=1.00"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 13
Summary for Link 4: Post Total
Inflow Area = 191,882 sf, Inflow Depth > 0.13" for 1-inch event
Inflow = 0.02 cfs @ 5.67 hrs, Volume= 2,150 cf
Primary = 0.02 cfs @ 5.67 hrs, Volume= 2,150 cf, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
N
U
3
0
LL
Link 4: Post Total
Hydrograph
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105 110 115 120
Time (hours)
❑ Inflow
❑ Primary

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-1 Charlotte 6-hr 1-inch Rainfall=1.00"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 14
Hydrograph for Link 4: Post Total
Time
Inflow
Elevation
Primary
(hours)
(cfs)
(feet)
(cfs)
0.00
0.00
0.00
0.00
2.00
0.00
0.00
0.00
4.00
0.01
0.00
0.01
6.00
0.02
0.00
0.02
8.00
0.01
0.00
0.01
10.00
0.01
0.00
0.01
12.00
0.01
0.00
0.01
14.00
0.01
0.00
0.01
16.00
0.01
0.00
0.01
18.00
0.01
0.00
0.01
20.00
0.01
0.00
0.01
22.00
0.01
0.00
0.01
24.00
0.01
0.00
0.01
26.00
0.01
0.00
0.01
28.00
0.01
0.00
0.01
30.00
0.01
0.00
0.01
32.00
0.01
0.00
0.01
34.00
0.01
0.00
0.01
36.00
0.01
0.00
0.01
38.00
0.01
0.00
0.01
40.00
0.01
0.00
0.01
42.00
0.01
0.00
0.01
44.00
0.01
0.00
0.01
46.00
0.01
0.00
0.01
48.00
0.01
0.00
0.01
50.00
0.01
0.00
0.01
52.00
0.01
0.00
0.01
54.00
0.00
0.00
0.00
56.00
0.00
0.00
0.00
58.00
0.00
0.00
0.00
60.00
0.00
0.00
0.00
62.00
0.00
0.00
0.00
64.00
0.00
0.00
0.00
66.00
0.00
0.00
0.00
68.00
0.00
0.00
0.00
70.00
0.00
0.00
0.00
72.00
0.00
0.00
0.00
74.00
0.00
0.00
0.00
76.00
0.00
0.00
0.00
78.00
0.00
0.00
0.00
80.00
0.00
0.00
0.00
82.00
0.00
0.00
0.00
84.00
0.00
0.00
0.00
86.00
0.00
0.00
0.00
88.00
0.00
0.00
0.00
90.00
0.00
0.00
0.00
92.00
0.00
0.00
0.00
94.00
0.00
0.00
0.00
96.00
0.00
0.00
0.00
98.00
0.00
0.00
0.00
100.00
0.00
0.00
0.00
Time
Inflow
Elevation
Primary
(hours)
(cfs)
(feet)
(cfs)
102.00
0.00
0.00
0.00
104.00
0.00
0.00
0.00
106.00
0.00
0.00
0.00
108.00
0.00
0.00
0.00
110.00
0.00
0.00
0.00
112.00
0.00
0.00
0.00
114.00
0.00
0.00
0.00
116.00
0.00
0.00
0.00
118.00
0.00
0.00
0.00
120.00
0.00
0.00
0.00

27
Post-D
ined
Post-Undetained
Sand Filter Post Total
S4
Reach on Link

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 2
Area Listing (all nodes)
Area CN Description
(sq-ft) (s u bcatch me nt- n u m be rs)
86,859 88 Post -Development Detained Areas (2)
93,698 70 Post -Development Undetained Areas (3)
11,326 98 Roofs, HSG B (2)
191,882 80 TOTAL AREA

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 24-hr 1-yr Rainfall=2.58"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 3
Time span=0.00-120.00 hrs, dt=0.02 hrs, 6001 points
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN
Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method
Subcatchment 2: Post -Detained Runoff Area=2.254 ac Runoff Depth=1.52"
Tc=5.0 min CN=89 Runoff=5.13 cfs 12,477 cf
Subcatchment 3: Post-Undetained Runoff Area=2.151 ac Runoff Depth=0.49"
Tc=10.0 min CN=70 Runoff=1.24 cfs 3,857 cf
Pond 2A: Sand Filter Peak Elev=668.38' Storage=7,092 cf Inflow=5.13 cfs 12,477 cf
Outflow=0.31 cfs 12,099 cf
Link 4: Post Total Inflow=1.51 cfs 15,957 cf
Primary=1.51 cfs 15,957 cf
Total Runoff Area = 191,882 sf Runoff Volume = 16,334 cf Average Runoff Depth = 1.02"

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 24-hr 1-yr Rainfall=2.58"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 4
Summary for Subcatchment 2: Post -Detained
Runoff = 5.13 cfs @ 11.99 hrs, Volume= 12,477 cf, Depth= 1.52"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Charlotte 24-hr 1-yr Rainfall=2.58"
Area (ac) CN Description
1.624 88 Post -Development Detained Areas
0.370 88 Post -Development Detained Areas
0.260 98 Roofs. HSG B
2.254 89 Weighted Average
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry, Post -Detained
■ Runoff

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 24-hr 1-yr Rainfall=2.58"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 5
Hydrograph for Subcatchment 2: Post -Detained
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
0.00
0.00
0.00
0.00
2.00
0.06
0.00
0.00
4.00
0.12
0.00
0.00
6.00
0.20
0.00
0.00
8.00
0.31
0.00
0.01
10.00
0.46
0.03
0.06
12.00
1.59
0.70
5.10
14.00
2.11
1.12
0.20
16.00
2.27
1.25
0.12
18.00
2.38
1.35
0.09
20.00
2.46
1.42
0.07
22.00
2.52
1.47
0.06
24.00
2.58
1.52
0.06
26.00
2.58
1.52
0.00
28.00
2.58
1.52
0.00
30.00
2.58
1.52
0.00
32.00
2.58
1.52
0.00
34.00
2.58
1.52
0.00
36.00
2.58
1.52
0.00
38.00
2.58
1.52
0.00
40.00
2.58
1.52
0.00
42.00
2.58
1.52
0.00
44.00
2.58
1.52
0.00
46.00
2.58
1.52
0.00
48.00
2.58
1.52
0.00
50.00
2.58
1.52
0.00
52.00
2.58
1.52
0.00
54.00
2.58
1.52
0.00
56.00
2.58
1.52
0.00
58.00
2.58
1.52
0.00
60.00
2.58
1.52
0.00
62.00
2.58
1.52
0.00
64.00
2.58
1.52
0.00
66.00
2.58
1.52
0.00
68.00
2.58
1.52
0.00
70.00
2.58
1.52
0.00
72.00
2.58
1.52
0.00
74.00
2.58
1.52
0.00
76.00
2.58
1.52
0.00
78.00
2.58
1.52
0.00
80.00
2.58
1.52
0.00
82.00
2.58
1.52
0.00
84.00
2.58
1.52
0.00
86.00
2.58
1.52
0.00
88.00
2.58
1.52
0.00
90.00
2.58
1.52
0.00
92.00
2.58
1.52
0.00
94.00
2.58
1.52
0.00
96.00
2.58
1.52
0.00
98.00
2.58
1.52
0.00
100.00
2.58
1.52
0.00
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
102.00
2.58
1.52
0.00
104.00
2.58
1.52
0.00
106.00
2.58
1.52
0.00
108.00
2.58
1.52
0.00
110.00
2.58
1.52
0.00
112.00
2.58
1.52
0.00
114.00
2.58
1.52
0.00
116.00
2.58
1.52
0.00
118.00
2.58
1.52
0.00
120.00
2.58
1.52
0.00

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 24-hr 1-yr Rainfall=2.58"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 6
Summary for Subcatchment 3: Post-Undetained
Runoff = 1.24 cfs @ 12.10 hrs, Volume= 3,857 cf, Depth= 0.49"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Charlotte 24-hr 1-yr Rainfall=2.58"
Area (ac) CN Description
2.151 70 Post -Development Undetained Areas
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
10.0 Direct Entry, Post-Undetained
❑ Runoff
N
U
3
0
LL

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 24-hr 1-yr Rainfall=2.58"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 7
Hydrograph for Subcatchment 3: Post-Undetained
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
0.00
0.00
0.00
0.00
2.00
0.06
0.00
0.00
4.00
0.12
0.00
0.00
6.00
0.20
0.00
0.00
8.00
0.31
0.00
0.00
10.00
0.46
0.00
0.00
12.00
1.59
0.11
0.79
14.00
2.11
0.28
0.09
16.00
2.27
0.35
0.06
18.00
2.38
0.40
0.05
20.00
2.46
0.43
0.04
22.00
2.52
0.47
0.03
24.00
2.58
0.49
0.03
26.00
2.58
0.49
0.00
28.00
2.58
0.49
0.00
30.00
2.58
0.49
0.00
32.00
2.58
0.49
0.00
34.00
2.58
0.49
0.00
36.00
2.58
0.49
0.00
38.00
2.58
0.49
0.00
40.00
2.58
0.49
0.00
42.00
2.58
0.49
0.00
44.00
2.58
0.49
0.00
46.00
2.58
0.49
0.00
48.00
2.58
0.49
0.00
50.00
2.58
0.49
0.00
52.00
2.58
0.49
0.00
54.00
2.58
0.49
0.00
56.00
2.58
0.49
0.00
58.00
2.58
0.49
0.00
60.00
2.58
0.49
0.00
62.00
2.58
0.49
0.00
64.00
2.58
0.49
0.00
66.00
2.58
0.49
0.00
68.00
2.58
0.49
0.00
70.00
2.58
0.49
0.00
72.00
2.58
0.49
0.00
74.00
2.58
0.49
0.00
76.00
2.58
0.49
0.00
78.00
2.58
0.49
0.00
80.00
2.58
0.49
0.00
82.00
2.58
0.49
0.00
84.00
2.58
0.49
0.00
86.00
2.58
0.49
0.00
88.00
2.58
0.49
0.00
90.00
2.58
0.49
0.00
92.00
2.58
0.49
0.00
94.00
2.58
0.49
0.00
96.00
2.58
0.49
0.00
98.00
2.58
0.49
0.00
100.00
2.58
0.49
0.00
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
102.00
2.58
0.49
0.00
104.00
2.58
0.49
0.00
106.00
2.58
0.49
0.00
108.00
2.58
0.49
0.00
110.00
2.58
0.49
0.00
112.00
2.58
0.49
0.00
114.00
2.58
0.49
0.00
116.00
2.58
0.49
0.00
118.00
2.58
0.49
0.00
120.00
2.58
0.49
0.00

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 24-hr 1-yr Rainfall=2.58"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 8
Summary for Pond 2A: Sand Filter
Inflow Area =
98,184 sf,
Inflow Depth = 1.52"
for 1-yr event
Inflow =
5.13 cfs @
11.99 hrs, Volume=
12,477 cf
Outflow =
0.31 cfs @
13.10 hrs, Volume=
12,099 cf, Atten= 94%, Lag= 66.5 min
Primary =
0.31 cfs @
13.10 hrs, Volume=
12,099 cf
Routing by Stor-Ind method, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Peak Elev= 668.38' @ 13.10 hrs Surf.Area= 3,608 sf Storage= 7,092 cf
Plug -Flow detention time= 686.2 min calculated for 12,097 cf (97% of inflow)
Center -of -Mass det. time= 669.2 min ( 1,487.6 - 818.4 )
Volume Invert
Avail.Storage Storage Description
#1 666.00'
34,734 cf Sand Filter (Conic) Listed below (Recalc)
Elevation Surf.Area
Inc.Store Cum.Store
Wet.Area
(feet)
(sq-ft)
(cubic -feet) (cubic -feet)
(sq-ft)
666.00
2,385
0 0
2,385
667.00
2,881
2,629 2,629
2,913
668.00
3,404
3,139 5,768
3,473
669.00
3,956
3,677 9,445
4,065
670.00
4,536
4,243 13,687
4,689
671.00
5,328
4,927 18,614
5,519
672.00
6,203
5,760 24,374
6,435
673.00
7,142
6,667 31,041
7,417
673.50
7,635
3,694 34,734
7,933
Device Routing
Invert
Outlet Devices
#1 Primary
666.00'
Sand Filter
Elev. (feet) 666.00 667.00 668.00
669.00 670.00 671.00 672.00
673.00
Disch. (cfs) 0.000 0.014 0.029 0.037 0.045 0.053 0.061 0.069
#2 Primary
666.90'
3.0" Vert. CP-Bleeder C= 0.600
#3 Primary
670.25'
48.0" x 48.0" Horiz. Orifice/Grate
C= 0.600
Limited to weir flow at low heads
#4 Device 3
662.47'
24.0" Round Culvert
L= 93.8' RCP, square edge headwall, Ke= 0.500
Inlet / Outlet Invert= 662.47' / 662.00' S= 0.0050 '/' Cc= 0.900
n= 0.013, Flow Area= 3.14 sf
Primary OutFlow Max=0.31 cfs @ 13.10 hrs HW=668.38' (Free Discharge)
1=Sand Filter (Custom Controls 0.03 cfs)
2=CP-Bleeder (Orifice Controls 0.27 cfs @ 5.60 fps)
3=Orifice/Grate ( Controls 0.00 cfs)
L4=Culvert ( Controls 0.00 cfs)

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 24-hr 1-yr Rainfall=2.58"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 9
Inflow
❑ Primary

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 24-hr 1-yr Rainfall=2.58"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 10
Hydrograph for Pond 2A: Sand Filter
Time
Inflow
Storage
Elevation
Primary
(hours)
(cfs)
(cubic -feet)
(feet)
(cfs)
0.00
0.00
0
666.00
0.00
4.00
0.00
0
666.00
0.00
8.00
0.01
19
666.01
0.00
12.00
5.10
4,278
667.55
0.19
16.00
0.12
5,946
668.05
0.27
20.00
0.07
4,039
667.47
0.18
24.00
0.06
3,016
667.13
0.09
28.00
0.00
2,445
666.94
0.02
32.00
0.00
2,247
666.87
0.01
36.00
0.00
2,079
666.81
0.01
40.00
0.00
1,922
666.75
0.01
44.00
0.00
1,777
666.70
0.01
48.00
0.00
1,641
666.65
0.01
52.00
0.00
1,516
666.60
0.01
56.00
0.00
1,400
666.56
0.01
60.00
0.00
1,292
666.51
0.01
64.00
0.00
1,192
666.48
0.01
68.00
0.00
1,099
666.44
0.01
72.00
0.00
1,014
666.41
0.01
76.00
0.00
935
666.38
0.01
80.00
0.00
861
666.35
0.00
84.00
0.00
794
666.32
0.00
88.00
0.00
731
666.30
0.00
92.00
0.00
674
666.27
0.00
96.00
0.00
620
666.25
0.00
100.00
0.00
571
666.23
0.00
104.00
0.00
526
666.22
0.00
108.00
0.00
484
666.20
0.00
112.00
0.00
446
666.18
0.00
116.00
0.00
410
666.17
0.00
120.00
0.00
377
666.16
0.00

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 24-hr 1-yr Rainfall=2.58"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 11
Elevation Primary
(feet)
(cfs)
666.00
0.00
666.04
0.00
666.08
0.00
666.12
0.00
666.16
0.00
666.20
0.00
666.24
0.00
666.28
0.00
666.32
0.00
666.36
0.01
666.40
0.01
666.44
0.01
666.48
0.01
666.52
0.01
666.56
0.01
666.60
0.01
666.64
0.01
666.68
0.01
666.72
0.01
666.76
0.01
666.80
0.01
666.84
0.01
666.88
0.01
666.92
0.01
666.96
0.02
667.00
0.03
667.04
0.05
667.08
0.07
667.12
0.09
667.16
0.10
667.20
0.12
667.24
0.13
667.28
0.14
667.32
0.15
667.36
0.16
667.40
0.16
667.44
0.17
667.48
0.18
667.52
0.19
667.56
0.20
667.60
0.20
667.64
0.21
667.68
0.22
667.72
0.22
667.76
0.23
667.80
0.23
667.84
0.24
667.88
0.25
667.92
0.25
667.96
0.26
668.00
0.26
Stage -Discharge for Pond 2A: Sand Filter
Elevation Primary
(feet)
(cfs)
668.04
0.27
668.08
0.27
668.12
0.28
668.16
0.28
668.20
0.29
668.24
0.29
668.28
0.30
668.32
0.30
668.36
0.30
668.40
0.31
668.44
0.31
668.48
0.32
668.52
0.32
668.56
0.33
668.60
0.33
668.64
0.33
668.68
0.34
668.72
0.34
668.76
0.35
668.80
0.35
668.84
0.35
668.88
0.36
668.92
0.36
668.96
0.37
669.00
0.37
669.04
0.37
669.08
0.38
669.12
0.38
669.16
0.38
669.20
0.39
669.24
0.39
669.28
0.39
669.32
0.40
669.36
0.40
669.40
0.40
669.44
0.41
669.48
0.41
669.52
0.41
669.56
0.42
669.60
0.42
669.64
0.42
669.68
0.43
669.72
0.43
669.76
0.43
669.80
0.44
669.84
0.44
669.88
0.44
669.92
0.45
669.96
0.45
670.00
0.45
670.04
0.46
Elevation Primary
(feet)
(cfs)
670.08
0.46
670.12
0.46
670.16
0.46
670.20
0.47
670.24
0.47
670.28
0.75
670.32
1.45
670.36
2.39
670.40
3.52
670.44
4.82
670.48
6.26
670.52
7.83
670.56
8.92
670.60
9.45
670.64
9.95
670.68
10.42
670.72
10.88
670.76
11.31
670.80
11.73
670.84
12.13
670.88
12.52
670.92
12.90
670.96
13.27
671.00
13.62
671.04
13.97
671.08
14.31
671.12
14.64
671.16
14.96
671.20
15.28
671.24
15.59
671.28
15.89
671.32
16.19
671.36
16.48
671.40
16.77
671.44
17.05
671.48
17.33
671.52
17.61
671.56
17.87
671.60
18.14
671.64
18.40
671.68
18.66
671.72
18.91
671.76
19.16
671.80
19.41
671.84
19.65
671.88
19.89
671.92
20.13
671.96
20.37
672.00
20.60
672.04
20.83
672.08
21.06
Elevation Primary
(feet)
(cfs)
672.12
21.28
672.16
21.50
672.20
21.72
672.24
21.94
672.28
22.16
672.32
22.37
672.36
22.58
672.40
22.79
672.44
23.00
672.48
23.21
672.52
23.41
672.56
23.61
672.60
23.81
672.64
24.01
672.68
24.21
672.72
24.40
672.76
24.60
672.80
24.79
672.84
24.98
672.88
25.17
672.92
25.36
672.96
25.55
673.00
25.73
673.04
25.92
673.08
26.10
673.12
26.28
673.16
26.46
673.20
26.64
673.24
26.82
673.28
26.99
673.32
27.17
673.36
27.34
673.40
27.52
673.44
27.69
673.48
27.86

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 24-hr 1-yr Rainfall=2.58"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 12
Stage -Area -Storage for Pond 2A: Sand Filter
Elevation
Surface
Storage
(feet)
(sq-ft)
(cubic -feet)
666.00
2,385
0
666.10
2,432
241
666.20
2,480
487
666.30
2,529
737
666.40
2,578
992
666.50
2,627
1,253
666.60
2,677
1,518
666.70
2,727
1,788
666.80
2,778
2,063
666.90
2,829
2,344
667.00
2,881
2,629
667.10
2,931
2,920
667.20
2,982
3,215
667.30
3,033
3,516
667.40
3,085
3,822
667.50
3,137
4,133
667.60
3,190
4,449
667.70
3,243
4,771
667.80
3,296
5,098
667.90
3,350
5,430
668.00
3,404
5,768
668.10
3,457
6,111
668.20
3,511
6,459
668.30
3,565
6,813
668.40
3,620
7,173
668.50
3,675
7,537
668.60
3,730
7,907
668.70
3,786
8,283
668.80
3,842
8,665
668.90
3,899
9,052
669.00
3,956
9,445
669.10
4,012
9,843
669.20
4,069
10,247
669.30
4,126
10,657
669.40
4,183
11,072
669.50
4,241
11,493
669.60
4,299
11,920
669.70
4,358
12,353
669.80
4,417
12,792
669.90
4,476
13,237
670.00
4,536
13,687
670.10
4,612
14,145
670.20
4,689
14,610
670.30
4,767
15,082
670.40
4,845
15,563
670.50
4,924
16,052
670.60
5,004
16,548
670.70
5,084
17,052
670.80
5,165
17,565
670.90
5,246
18,085
671.00
5,328
18,614
Elevation
Surface
Storage
(feet)
(sq-ft)
(cubic -feet)
671.10
5,413
19,151
671.20
5,498
19,696
671.30
5,584
20,250
671.40
5,670
20,813
671.50
5,757
21,385
671.60
5,845
21,965
671.70
5,934
22,554
671.80
6,023
23,151
671.90
6,113
23,758
672.00
6,203
24,374
672.10
6,294
24,999
672.20
6,386
25,633
672.30
6,478
26,276
672.40
6,571
26,928
672.50
6,664
27,590
672.60
6,758
28,261
672.70
6,853
28,942
672.80
6,949
29,632
672.90
7,045
30,331
673.00
7,142
31,041
673.10
7,239
31,760
673.20
7,337
32,489
673.30
7,436
33,227
673.40
7,535
33,976
673.50
7,635
34,734

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 24-hr 1-yr Rainfall=2.58"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 13
Summary for Link 4: Post Total
Inflow Area = 191,882 sf, Inflow Depth > 1.00" for 1-yr event
Inflow = 1.51 cfs @ 12.10 hrs, Volume= 15,957 cf
Primary = 1.51 cfs @ 12.10 hrs, Volume= 15,957 cf, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
❑ Inflow
❑ Primary
N
U
3
0
LL

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 24-hr 1-yr Rainfall=2.58"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 14
Hydrograph for Link 4: Post Total
Time
Inflow
Elevation
Primary
(hours)
(cfs)
(feet)
(cfs)
0.00
0.00
0.00
0.00
2.00
0.00
0.00
0.00
4.00
0.00
0.00
0.00
6.00
0.00
0.00
0.00
8.00
0.00
0.00
0.00
10.00
0.00
0.00
0.00
12.00
0.99
0.00
0.99
14.00
0.39
0.00
0.39
16.00
0.33
0.00
0.33
18.00
0.27
0.00
0.27
20.00
0.21
0.00
0.21
22.00
0.16
0.00
0.16
24.00
0.12
0.00
0.12
26.00
0.03
0.00
0.03
28.00
0.02
0.00
0.02
30.00
0.01
0.00
0.01
32.00
0.01
0.00
0.01
34.00
0.01
0.00
0.01
36.00
0.01
0.00
0.01
38.00
0.01
0.00
0.01
40.00
0.01
0.00
0.01
42.00
0.01
0.00
0.01
44.00
0.01
0.00
0.01
46.00
0.01
0.00
0.01
48.00
0.01
0.00
0.01
50.00
0.01
0.00
0.01
52.00
0.01
0.00
0.01
54.00
0.01
0.00
0.01
56.00
0.01
0.00
0.01
58.00
0.01
0.00
0.01
60.00
0.01
0.00
0.01
62.00
0.01
0.00
0.01
64.00
0.01
0.00
0.01
66.00
0.01
0.00
0.01
68.00
0.01
0.00
0.01
70.00
0.01
0.00
0.01
72.00
0.01
0.00
0.01
74.00
0.01
0.00
0.01
76.00
0.01
0.00
0.01
78.00
0.01
0.00
0.01
80.00
0.00
0.00
0.00
82.00
0.00
0.00
0.00
84.00
0.00
0.00
0.00
86.00
0.00
0.00
0.00
88.00
0.00
0.00
0.00
90.00
0.00
0.00
0.00
92.00
0.00
0.00
0.00
94.00
0.00
0.00
0.00
96.00
0.00
0.00
0.00
98.00
0.00
0.00
0.00
100.00
0.00
0.00
0.00
Time
Inflow
Elevation
Primary
(hours)
(cfs)
(feet)
(cfs)
102.00
0.00
0.00
0.00
104.00
0.00
0.00
0.00
106.00
0.00
0.00
0.00
108.00
0.00
0.00
0.00
110.00
0.00
0.00
0.00
112.00
0.00
0.00
0.00
114.00
0.00
0.00
0.00
116.00
0.00
0.00
0.00
118.00
0.00
0.00
0.00
120.00
0.00
0.00
0.00

27
Post-D
ined
Post-Undetained
Sand Filter Post Total
S4
Reach on Link

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 2
Area Listing (all nodes)
Area CN Description
(sq-ft) (s u bcatch me nt- n u m be rs)
86,859 88 Post -Development Detained Areas (2)
93,698 70 Post -Development Undetained Areas (3)
11,326 98 Roofs, HSG B (2)
191,882 80 TOTAL AREA

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 6-hr 10-yr Rainfall=3.72"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 3
Time span=0.00-120.00 hrs, dt=0.02 hrs, 6001 points
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN
Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method
Subcatchment 2: Post -Detained Runoff Area=2.254 ac Runoff Depth=2.56"
Tc=5.0 min CN=89 Runoff=11.45 cfs 20,956 cf
Subcatchment 3: Post-Undetained Runoff Area=2.151 ac Runoff Depth=1.15"
Tc=10.0 min CN=70 Runoff=4.12 cfs 8,952 cf
Pond 2A: Sand Filter Peak Elev=670.30' Storage=15,096 cf Inflow=11.45 cfs 20,956 cf
Outflow=1.22 cfs 20,632 cf
Link 4: Post Total Inflow=4.51 cfs 29,584 cf
Primary=4.51 cfs 29,584 cf
Total Runoff Area = 191,882 sf Runoff Volume = 29,908 cf Average Runoff Depth = 1.87"

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 6-hr 10-yr Rainfall=3.72"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 4
Summary for Subcatchment 2: Post -Detained
Runoff = 11.45 cfs @ 3.15 hrs, Volume= 20,956 cf, Depth= 2.56"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 10-yr Rainfall=3.72"
Area (ac) CN Description
1.624 88 Post -Development Detained Areas
0.370 88 Post -Development Detained Areas
0.260 98 Roofs. HSG B
2.254 89 Weighted Average
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry, Post -Detained
Subcatchment 2: Post -Detained
Hydrograph
N
U
3
0
LL
■ Runoff

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 6-hr 10-yr Rainfall=3.72"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 5
Hydrograph for Subcatchment 2: Post -Detained
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
0.00
0.00
0.00
0.00
2.00
0.39
0.02
0.12
4.00
3.29
2.16
1.00
6.00
3.72
2.56
0.28
8.00
3.72
2.56
0.00
10.00
3.72
2.56
0.00
12.00
3.72
2.56
0.00
14.00
3.72
2.56
0.00
16.00
3.72
2.56
0.00
18.00
3.72
2.56
0.00
20.00
3.72
2.56
0.00
22.00
3.72
2.56
0.00
24.00
3.72
2.56
0.00
26.00
3.72
2.56
0.00
28.00
3.72
2.56
0.00
30.00
3.72
2.56
0.00
32.00
3.72
2.56
0.00
34.00
3.72
2.56
0.00
36.00
3.72
2.56
0.00
38.00
3.72
2.56
0.00
40.00
3.72
2.56
0.00
42.00
3.72
2.56
0.00
44.00
3.72
2.56
0.00
46.00
3.72
2.56
0.00
48.00
3.72
2.56
0.00
50.00
3.72
2.56
0.00
52.00
3.72
2.56
0.00
54.00
3.72
2.56
0.00
56.00
3.72
2.56
0.00
58.00
3.72
2.56
0.00
60.00
3.72
2.56
0.00
62.00
3.72
2.56
0.00
64.00
3.72
2.56
0.00
66.00
3.72
2.56
0.00
68.00
3.72
2.56
0.00
70.00
3.72
2.56
0.00
72.00
3.72
2.56
0.00
74.00
3.72
2.56
0.00
76.00
3.72
2.56
0.00
78.00
3.72
2.56
0.00
80.00
3.72
2.56
0.00
82.00
3.72
2.56
0.00
84.00
3.72
2.56
0.00
86.00
3.72
2.56
0.00
88.00
3.72
2.56
0.00
90.00
3.72
2.56
0.00
92.00
3.72
2.56
0.00
94.00
3.72
2.56
0.00
96.00
3.72
2.56
0.00
98.00
3.72
2.56
0.00
100.00
3.72
2.56
0.00
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
102.00
3.72
2.56
0.00
104.00
3.72
2.56
0.00
106.00
3.72
2.56
0.00
108.00
3.72
2.56
0.00
110.00
3.72
2.56
0.00
112.00
3.72
2.56
0.00
114.00
3.72
2.56
0.00
116.00
3.72
2.56
0.00
118.00
3.72
2.56
0.00
120.00
3.72
2.56
0.00

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 6-hr 10-yr Rainfall=3.72"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 6
Summary for Subcatchment 3: Post-Undetained
Runoff = 4.12 cfs @ 3.24 hrs, Volume= 8,952 cf, Depth= 1.15"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 10-yr Rainfall=3.72"
Area (ac) CN Description
2.151 70 Post -Development Undetained Areas
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
10.0 Direct Entry, Post-Undetained
■ Runoff
N
U
3
0
LL

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 6-hr 10-yr Rainfall=3.72"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 7
Hydrograph for Subcatchment 3: Post-Undetained
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
0.00
0.00
0.00
0.00
2.00
0.39
0.00
0.00
4.00
3.29
0.88
0.65
6.00
3.72
1.15
0.19
8.00
3.72
1.15
0.00
10.00
3.72
1.15
0.00
12.00
3.72
1.15
0.00
14.00
3.72
1.15
0.00
16.00
3.72
1.15
0.00
18.00
3.72
1.15
0.00
20.00
3.72
1.15
0.00
22.00
3.72
1.15
0.00
24.00
3.72
1.15
0.00
26.00
3.72
1.15
0.00
28.00
3.72
1.15
0.00
30.00
3.72
1.15
0.00
32.00
3.72
1.15
0.00
34.00
3.72
1.15
0.00
36.00
3.72
1.15
0.00
38.00
3.72
1.15
0.00
40.00
3.72
1.15
0.00
42.00
3.72
1.15
0.00
44.00
3.72
1.15
0.00
46.00
3.72
1.15
0.00
48.00
3.72
1.15
0.00
50.00
3.72
1.15
0.00
52.00
3.72
1.15
0.00
54.00
3.72
1.15
0.00
56.00
3.72
1.15
0.00
58.00
3.72
1.15
0.00
60.00
3.72
1.15
0.00
62.00
3.72
1.15
0.00
64.00
3.72
1.15
0.00
66.00
3.72
1.15
0.00
68.00
3.72
1.15
0.00
70.00
3.72
1.15
0.00
72.00
3.72
1.15
0.00
74.00
3.72
1.15
0.00
76.00
3.72
1.15
0.00
78.00
3.72
1.15
0.00
80.00
3.72
1.15
0.00
82.00
3.72
1.15
0.00
84.00
3.72
1.15
0.00
86.00
3.72
1.15
0.00
88.00
3.72
1.15
0.00
90.00
3.72
1.15
0.00
92.00
3.72
1.15
0.00
94.00
3.72
1.15
0.00
96.00
3.72
1.15
0.00
98.00
3.72
1.15
0.00
100.00
3.72
1.15
0.00
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
102.00
3.72
1.15
0.00
104.00
3.72
1.15
0.00
106.00
3.72
1.15
0.00
108.00
3.72
1.15
0.00
110.00
3.72
1.15
0.00
112.00
3.72
1.15
0.00
114.00
3.72
1.15
0.00
116.00
3.72
1.15
0.00
118.00
3.72
1.15
0.00
120.00
3.72
1.15
0.00

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 6-hr 10-yr Rainfall=3.72"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 8
Summary for Pond 2A: Sand Filter
Inflow Area =
98,184 sf,
Inflow Depth = 2.56"
for 10-yr event
Inflow =
11.45 cfs @
3.15 hrs, Volume=
20,956 cf
Outflow =
1.22 cfs @
3.79 hrs, Volume=
20,632 cf, Atten= 89%, Lag= 38.3 min
Primary =
1.22 cfs @
3.79 hrs, Volume=
20,632 cf
Routing by Stor-Ind method, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Peak Elev= 670.30' @ 3.79 hrs Surf.Area= 4,769 sf Storage= 15,096 cf
Plug -Flow detention time= 589.9 min calculated for 20,632 cf (98% of inflow)
Center -of -Mass det. time= 587.6 min ( 795.0 - 207.4 )
Volume Invert
Avail.Storage Storage Description
#1 666.00'
34,734 cf Sand Filter (Conic) Listed below (Recalc)
Elevation Surf.Area
Inc.Store Cum.Store
Wet.Area
(feet)
(sq-ft)
(cubic -feet) (cubic -feet)
(sq-ft)
666.00
2,385
0 0
2,385
667.00
2,881
2,629 2,629
2,913
668.00
3,404
3,139 5,768
3,473
669.00
3,956
3,677 9,445
4,065
670.00
4,536
4,243 13,687
4,689
671.00
5,328
4,927 18,614
5,519
672.00
6,203
5,760 24,374
6,435
673.00
7,142
6,667 31,041
7,417
673.50
7,635
3,694 34,734
7,933
Device Routing
Invert
Outlet Devices
#1 Primary
666.00'
Sand Filter
Elev. (feet) 666.00 667.00 668.00
669.00 670.00 671.00 672.00
673.00
Disch. (cfs) 0.000 0.014 0.029 0.037 0.045 0.053 0.061 0.069
#2 Primary
666.90'
3.0" Vert. CP-Bleeder C= 0.600
#3 Primary
670.25'
48.0" x 48.0" Horiz. Orifice/Grate
C= 0.600
Limited to weir flow at low heads
#4 Device 3
662.47'
24.0" Round Culvert
L= 93.8' RCP, square edge headwall, Ke= 0.500
Inlet / Outlet Invert= 662.47' / 662.00' S= 0.0050 '/' Cc= 0.900
n= 0.013, Flow Area= 3.14 sf
Primary OutFlow Max=1.11 cfs @ 3.79 hrs HW=670.30' (Free Discharge)
1=Sand Filter (Custom Controls 0.05 cfs)
2=CP-Bleeder (Orifice Controls 0.43 cfs @ 8.72 fps)
3=Orifice/Grate (Weir Controls 0.64 cfs @ 0.75 fps)
L4=Culvert (Passes 0.64 cfs of 3.48 cfs potential flow)

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 6-hr 10-yr Rainfall=3.72"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 9
FL-1 n —fI o—w
❑ Primary

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 6-hr 10-yr Rainfall=3.72"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 10
Hydrograph for Pond 2A: Sand Filter
Time
Inflow
Storage
Elevation
Primary
(hours)
(cfs)
(cubic -feet)
(feet)
(cfs)
0.00
0.00
0
666.00
0.00
4.00
1.00
15,057
670.29
1.06
8.00
0.00
11,301
669.45
0.41
12.00
0.00
6,304
668.16
0.28
16.00
0.00
3,335
667.24
0.13
20.00
0.00
2,500
666.96
0.02
24.00
0.00
2,281
666.88
0.01
28.00
0.00
2,110
666.82
0.01
32.00
0.00
1,951
666.76
0.01
36.00
0.00
1,803
666.71
0.01
40.00
0.00
1,666
666.66
0.01
44.00
0.00
1,539
666.61
0.01
48.00
0.00
1,421
666.56
0.01
52.00
0.00
1,312
666.52
0.01
56.00
0.00
1,210
666.48
0.01
60.00
0.00
1,116
666.45
0.01
64.00
0.00
1,029
666.41
0.01
68.00
0.00
949
666.38
0.01
72.00
0.00
875
666.35
0.00
76.00
0.00
806
666.33
0.00
80.00
0.00
743
666.30
0.00
84.00
0.00
684
666.28
0.00
88.00
0.00
630
666.26
0.00
92.00
0.00
580
666.24
0.00
96.00
0.00
534
666.22
0.00
100.00
0.00
492
666.20
0.00
104.00
0.00
453
666.19
0.00
108.00
0.00
417
666.17
0.00
112.00
0.00
383
666.16
0.00
116.00
0.00
353
666.15
0.00
120.00
0.00
325
666.13
0.00

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 6-hr 10-yr Rainfall=3.72"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 11
Elevation Primary
(feet)
(cfs)
666.00
0.00
666.04
0.00
666.08
0.00
666.12
0.00
666.16
0.00
666.20
0.00
666.24
0.00
666.28
0.00
666.32
0.00
666.36
0.01
666.40
0.01
666.44
0.01
666.48
0.01
666.52
0.01
666.56
0.01
666.60
0.01
666.64
0.01
666.68
0.01
666.72
0.01
666.76
0.01
666.80
0.01
666.84
0.01
666.88
0.01
666.92
0.01
666.96
0.02
667.00
0.03
667.04
0.05
667.08
0.07
667.12
0.09
667.16
0.10
667.20
0.12
667.24
0.13
667.28
0.14
667.32
0.15
667.36
0.16
667.40
0.16
667.44
0.17
667.48
0.18
667.52
0.19
667.56
0.20
667.60
0.20
667.64
0.21
667.68
0.22
667.72
0.22
667.76
0.23
667.80
0.23
667.84
0.24
667.88
0.25
667.92
0.25
667.96
0.26
668.00
0.26
Stage -Discharge for Pond 2A: Sand Filter
Elevation Primary
(feet)
(cfs)
668.04
0.27
668.08
0.27
668.12
0.28
668.16
0.28
668.20
0.29
668.24
0.29
668.28
0.30
668.32
0.30
668.36
0.30
668.40
0.31
668.44
0.31
668.48
0.32
668.52
0.32
668.56
0.33
668.60
0.33
668.64
0.33
668.68
0.34
668.72
0.34
668.76
0.35
668.80
0.35
668.84
0.35
668.88
0.36
668.92
0.36
668.96
0.37
669.00
0.37
669.04
0.37
669.08
0.38
669.12
0.38
669.16
0.38
669.20
0.39
669.24
0.39
669.28
0.39
669.32
0.40
669.36
0.40
669.40
0.40
669.44
0.41
669.48
0.41
669.52
0.41
669.56
0.42
669.60
0.42
669.64
0.42
669.68
0.43
669.72
0.43
669.76
0.43
669.80
0.44
669.84
0.44
669.88
0.44
669.92
0.45
669.96
0.45
670.00
0.45
670.04
0.46
Elevation Primary
(feet)
(cfs)
670.08
0.46
670.12
0.46
670.16
0.46
670.20
0.47
670.24
0.47
670.28
0.75
670.32
1.45
670.36
2.39
670.40
3.52
670.44
4.82
670.48
6.26
670.52
7.83
670.56
8.92
670.60
9.45
670.64
9.95
670.68
10.42
670.72
10.88
670.76
11.31
670.80
11.73
670.84
12.13
670.88
12.52
670.92
12.90
670.96
13.27
671.00
13.62
671.04
13.97
671.08
14.31
671.12
14.64
671.16
14.96
671.20
15.28
671.24
15.59
671.28
15.89
671.32
16.19
671.36
16.48
671.40
16.77
671.44
17.05
671.48
17.33
671.52
17.61
671.56
17.87
671.60
18.14
671.64
18.40
671.68
18.66
671.72
18.91
671.76
19.16
671.80
19.41
671.84
19.65
671.88
19.89
671.92
20.13
671.96
20.37
672.00
20.60
672.04
20.83
672.08
21.06
Elevation Primary
(feet)
(cfs)
672.12
21.28
672.16
21.50
672.20
21.72
672.24
21.94
672.28
22.16
672.32
22.37
672.36
22.58
672.40
22.79
672.44
23.00
672.48
23.21
672.52
23.41
672.56
23.61
672.60
23.81
672.64
24.01
672.68
24.21
672.72
24.40
672.76
24.60
672.80
24.79
672.84
24.98
672.88
25.17
672.92
25.36
672.96
25.55
673.00
25.73
673.04
25.92
673.08
26.10
673.12
26.28
673.16
26.46
673.20
26.64
673.24
26.82
673.28
26.99
673.32
27.17
673.36
27.34
673.40
27.52
673.44
27.69
673.48
27.86

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 6-hr 10-yr Rainfall=3.72"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 12
Stage -Area -Storage for Pond 2A: Sand Filter
Elevation
Surface
Storage
(feet)
(sq-ft)
(cubic -feet)
666.00
2,385
0
666.10
2,432
241
666.20
2,480
487
666.30
2,529
737
666.40
2,578
992
666.50
2,627
1,253
666.60
2,677
1,518
666.70
2,727
1,788
666.80
2,778
2,063
666.90
2,829
2,344
667.00
2,881
2,629
667.10
2,931
2,920
667.20
2,982
3,215
667.30
3,033
3,516
667.40
3,085
3,822
667.50
3,137
4,133
667.60
3,190
4,449
667.70
3,243
4,771
667.80
3,296
5,098
667.90
3,350
5,430
668.00
3,404
5,768
668.10
3,457
6,111
668.20
3,511
6,459
668.30
3,565
6,813
668.40
3,620
7,173
668.50
3,675
7,537
668.60
3,730
7,907
668.70
3,786
8,283
668.80
3,842
8,665
668.90
3,899
9,052
669.00
3,956
9,445
669.10
4,012
9,843
669.20
4,069
10,247
669.30
4,126
10,657
669.40
4,183
11,072
669.50
4,241
11,493
669.60
4,299
11,920
669.70
4,358
12,353
669.80
4,417
12,792
669.90
4,476
13,237
670.00
4,536
13,687
670.10
4,612
14,145
670.20
4,689
14,610
670.30
4,767
15,082
670.40
4,845
15,563
670.50
4,924
16,052
670.60
5,004
16,548
670.70
5,084
17,052
670.80
5,165
17,565
670.90
5,246
18,085
671.00
5,328
18,614
Elevation
Surface
Storage
(feet)
(sq-ft)
(cubic -feet)
671.10
5,413
19,151
671.20
5,498
19,696
671.30
5,584
20,250
671.40
5,670
20,813
671.50
5,757
21,385
671.60
5,845
21,965
671.70
5,934
22,554
671.80
6,023
23,151
671.90
6,113
23,758
672.00
6,203
24,374
672.10
6,294
24,999
672.20
6,386
25,633
672.30
6,478
26,276
672.40
6,571
26,928
672.50
6,664
27,590
672.60
6,758
28,261
672.70
6,853
28,942
672.80
6,949
29,632
672.90
7,045
30,331
673.00
7,142
31,041
673.10
7,239
31,760
673.20
7,337
32,489
673.30
7,436
33,227
673.40
7,535
33,976
673.50
7,635
34,734

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 6-hr 10-yr Rainfall=3.72"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 13
Summary for Link 4: Post Total
Inflow Area = 191,882 sf, Inflow Depth > 1.85" for 10-yr event
Inflow = 4.51 cfs @ 3.24 hrs, Volume= 29,584 cf
Primary = 4.51 cfs @ 3.24 hrs, Volume= 29,584 cf, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
❑ Inflow
❑ Primary
N
U
3
0
LL

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 6-hr 10-yr Rainfall=3.72"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 14
Hydrograph for Link 4: Post Total
Time
Inflow
Elevation
Primary
(hours)
(cfs)
(feet)
(cfs)
0.00
0.00
0.00
0.00
2.00
0.00
0.00
0.00
4.00
1.71
0.00
1.71
6.00
0.66
0.00
0.66
8.00
0.41
0.00
0.41
10.00
0.35
0.00
0.35
12.00
0.28
0.00
0.28
14.00
0.21
0.00
0.21
16.00
0.13
0.00
0.13
18.00
0.05
0.00
0.05
20.00
0.02
0.00
0.02
22.00
0.01
0.00
0.01
24.00
0.01
0.00
0.01
26.00
0.01
0.00
0.01
28.00
0.01
0.00
0.01
30.00
0.01
0.00
0.01
32.00
0.01
0.00
0.01
34.00
0.01
0.00
0.01
36.00
0.01
0.00
0.01
38.00
0.01
0.00
0.01
40.00
0.01
0.00
0.01
42.00
0.01
0.00
0.01
44.00
0.01
0.00
0.01
46.00
0.01
0.00
0.01
48.00
0.01
0.00
0.01
50.00
0.01
0.00
0.01
52.00
0.01
0.00
0.01
54.00
0.01
0.00
0.01
56.00
0.01
0.00
0.01
58.00
0.01
0.00
0.01
60.00
0.01
0.00
0.01
62.00
0.01
0.00
0.01
64.00
0.01
0.00
0.01
66.00
0.01
0.00
0.01
68.00
0.01
0.00
0.01
70.00
0.01
0.00
0.01
72.00
0.00
0.00
0.00
74.00
0.00
0.00
0.00
76.00
0.00
0.00
0.00
78.00
0.00
0.00
0.00
80.00
0.00
0.00
0.00
82.00
0.00
0.00
0.00
84.00
0.00
0.00
0.00
86.00
0.00
0.00
0.00
88.00
0.00
0.00
0.00
90.00
0.00
0.00
0.00
92.00
0.00
0.00
0.00
94.00
0.00
0.00
0.00
96.00
0.00
0.00
0.00
98.00
0.00
0.00
0.00
100.00
0.00
0.00
0.00
Time
Inflow
Elevation
Primary
(hours)
(cfs)
(feet)
(cfs)
102.00
0.00
0.00
0.00
104.00
0.00
0.00
0.00
106.00
0.00
0.00
0.00
108.00
0.00
0.00
0.00
110.00
0.00
0.00
0.00
112.00
0.00
0.00
0.00
114.00
0.00
0.00
0.00
116.00
0.00
0.00
0.00
118.00
0.00
0.00
0.00
120.00
0.00
0.00
0.00

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 6-hr 25-yr Rainfall=4.38"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 15
Time span=0.00-120.00 hrs, dt=0.02 hrs, 6001 points
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN
Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method
Subcatchment 2: Post -Detained Runoff Area=2.254 ac Runoff Depth=3.18"
Tc=5.0 min CN=89 Runoff=13.82 cfs 26,030 cf
Subcatchment 3: Post-Undetained Runoff Area=2.151 ac Runoff Depth=1.59"
Tc=10.0 min CN=70 Runoff=5.73 cfs 12,410 cf
Pond 2A: Sand Filter Peak Elev=670.42' Storage=15,662 cf Inflow=13.82 cfs 26,030 cf
Outflow=4.18 cfs 25,704 cf
Link 4: Post Total Inflow=8.08 cfs 38,114 cf
Primary=8.08 cfs 38,114 cf
Total Runoff Area = 191,882 sf Runoff Volume = 38,440 cf Average Runoff Depth = 2.40"

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 6-hr 25-yr Rainfall=4.38"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 16
Summary for Subcatchment 2: Post -Detained
Runoff = 13.82 cfs @ 3.15 hrs, Volume= 26,030 cf, Depth= 3.18"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 25-yr Rainfall=4.38"
Area (ac) CN Description
1.624 88 Post -Development Detained Areas
0.370 88 Post -Development Detained Areas
0.260 98 Roofs, HSG B
2.254 89 Weighted Average
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry, Post -Detained
N
U
3
0
LL
Subcatchment 2: Post -Detained
Hydrograph
Time (hours)
■ Runoff

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 6-hr 25-yr Rainfall=4.38"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 17
Hydrograph for Subcatchment 2: Post -Detained
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
0.00
0.00
0.00
0.00
2.00
0.48
0.04
0.22
4.00
3.87
2.70
1.22
6.00
4.38
3.18
0.37
8.00
4.38
3.18
0.00
10.00
4.38
3.18
0.00
12.00
4.38
3.18
0.00
14.00
4.38
3.18
0.00
16.00
4.38
3.18
0.00
18.00
4.38
3.18
0.00
20.00
4.38
3.18
0.00
22.00
4.38
3.18
0.00
24.00
4.38
3.18
0.00
26.00
4.38
3.18
0.00
28.00
4.38
3.18
0.00
30.00
4.38
3.18
0.00
32.00
4.38
3.18
0.00
34.00
4.38
3.18
0.00
36.00
4.38
3.18
0.00
38.00
4.38
3.18
0.00
40.00
4.38
3.18
0.00
42.00
4.38
3.18
0.00
44.00
4.38
3.18
0.00
46.00
4.38
3.18
0.00
48.00
4.38
3.18
0.00
50.00
4.38
3.18
0.00
52.00
4.38
3.18
0.00
54.00
4.38
3.18
0.00
56.00
4.38
3.18
0.00
58.00
4.38
3.18
0.00
60.00
4.38
3.18
0.00
62.00
4.38
3.18
0.00
64.00
4.38
3.18
0.00
66.00
4.38
3.18
0.00
68.00
4.38
3.18
0.00
70.00
4.38
3.18
0.00
72.00
4.38
3.18
0.00
74.00
4.38
3.18
0.00
76.00
4.38
3.18
0.00
78.00
4.38
3.18
0.00
80.00
4.38
3.18
0.00
82.00
4.38
3.18
0.00
84.00
4.38
3.18
0.00
86.00
4.38
3.18
0.00
88.00
4.38
3.18
0.00
90.00
4.38
3.18
0.00
92.00
4.38
3.18
0.00
94.00
4.38
3.18
0.00
96.00
4.38
3.18
0.00
98.00
4.38
3.18
0.00
100.00
4.38
3.18
0.00
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
102.00
4.38
3.18
0.00
104.00
4.38
3.18
0.00
106.00
4.38
3.18
0.00
108.00
4.38
3.18
0.00
110.00
4.38
3.18
0.00
112.00
4.38
3.18
0.00
114.00
4.38
3.18
0.00
116.00
4.38
3.18
0.00
118.00
4.38
3.18
0.00
120.00
4.38
3.18
0.00

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 6-hr 25-yr Rainfall=4.38"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 18
Summary for Subcatchment 3: Post-Undetained
Runoff = 5.73 cfs @ 3.23 hrs, Volume= 12,410 cf, Depth= 1.59"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 25-yr Rainfall=4.38"
Area (ac) CN Description
2.151 70 Post -Development Undetained Areas
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
10.0 Direct Entry, Post-Undetained
■ Runoff
N
U
3
0
LL

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 6-hr 25-yr Rainfall=4.38"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 19
Hydrograph for Subcatchment 3: Post-Undetained
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
0.00
0.00
0.00
0.00
2.00
0.48
0.00
0.00
4.00
3.87
1.24
0.86
6.00
4.38
1.59
0.27
8.00
4.38
1.59
0.00
10.00
4.38
1.59
0.00
12.00
4.38
1.59
0.00
14.00
4.38
1.59
0.00
16.00
4.38
1.59
0.00
18.00
4.38
1.59
0.00
20.00
4.38
1.59
0.00
22.00
4.38
1.59
0.00
24.00
4.38
1.59
0.00
26.00
4.38
1.59
0.00
28.00
4.38
1.59
0.00
30.00
4.38
1.59
0.00
32.00
4.38
1.59
0.00
34.00
4.38
1.59
0.00
36.00
4.38
1.59
0.00
38.00
4.38
1.59
0.00
40.00
4.38
1.59
0.00
42.00
4.38
1.59
0.00
44.00
4.38
1.59
0.00
46.00
4.38
1.59
0.00
48.00
4.38
1.59
0.00
50.00
4.38
1.59
0.00
52.00
4.38
1.59
0.00
54.00
4.38
1.59
0.00
56.00
4.38
1.59
0.00
58.00
4.38
1.59
0.00
60.00
4.38
1.59
0.00
62.00
4.38
1.59
0.00
64.00
4.38
1.59
0.00
66.00
4.38
1.59
0.00
68.00
4.38
1.59
0.00
70.00
4.38
1.59
0.00
72.00
4.38
1.59
0.00
74.00
4.38
1.59
0.00
76.00
4.38
1.59
0.00
78.00
4.38
1.59
0.00
80.00
4.38
1.59
0.00
82.00
4.38
1.59
0.00
84.00
4.38
1.59
0.00
86.00
4.38
1.59
0.00
88.00
4.38
1.59
0.00
90.00
4.38
1.59
0.00
92.00
4.38
1.59
0.00
94.00
4.38
1.59
0.00
96.00
4.38
1.59
0.00
98.00
4.38
1.59
0.00
100.00
4.38
1.59
0.00
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
102.00
4.38
1.59
0.00
104.00
4.38
1.59
0.00
106.00
4.38
1.59
0.00
108.00
4.38
1.59
0.00
110.00
4.38
1.59
0.00
112.00
4.38
1.59
0.00
114.00
4.38
1.59
0.00
116.00
4.38
1.59
0.00
118.00
4.38
1.59
0.00
120.00
4.38
1.59
0.00

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 6-hr 25-yr Rainfall=4.38"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 20
Summary for Pond 2A: Sand Filter
Inflow Area =
98,184 sf,
Inflow Depth = 3.18"
for 25-yr event
Inflow =
13.82 cfs @
3.15 hrs, Volume=
26,030 cf
Outflow =
4.18 cfs @
3.38 hrs, Volume=
25,704 cf, Atten= 70%, Lag= 13.7 min
Primary =
4.18 cfs @
3.38 hrs, Volume=
25,704 cf
Routing by Stor-Ind method, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Peak Elev= 670.42' @ 3.38 hrs Surf.Area= 4,861 sf Storage= 15,662 cf
Plug -Flow detention time= 485.0 min calculated for 25,704 cf (99% of inflow)
Center -of -Mass det. time= 483.1 min (689.3 - 206.2 )
Volume Invert
Avail.Storage Storage Description
#1 666.00'
34,734 cf Sand Filter (Conic) Listed below (Recalc)
Elevation Surf.Area
Inc.Store Cum.Store
Wet.Area
(feet)
(sq-ft)
(cubic -feet) (cubic -feet)
(sq-ft)
666.00
2,385
0 0
2,385
667.00
2,881
2,629 2,629
2,913
668.00
3,404
3,139 5,768
3,473
669.00
3,956
3,677 9,445
4,065
670.00
4,536
4,243 13,687
4,689
671.00
5,328
4,927 18,614
5,519
672.00
6,203
5,760 24,374
6,435
673.00
7,142
6,667 31,041
7,417
673.50
7,635
3,694 34,734
7,933
Device Routing
Invert
Outlet Devices
#1 Primary
666.00'
Sand Filter
Elev. (feet) 666.00 667.00 668.00
669.00 670.00 671.00 672.00
673.00
Disch. (cfs) 0.000 0.014 0.029 0.037 0.045 0.053 0.061 0.069
#2 Primary
666.90'
3.0" Vert. CP-Bleeder C= 0.600
#3 Primary
670.25'
48.0" x 48.0" Horiz. Orifice/Grate
C= 0.600
Limited to weir flow at low heads
#4 Device 3
662.47'
24.0" Round Culvert
L= 93.8' RCP, square edge headwall, Ke= 0.500
Inlet / Outlet Invert= 662.47' / 662.00' S= 0.0050 '/' Cc= 0.900
n= 0.013, Flow Area= 3.14 sf
Primary OutFlow Max=4.15 cfs @ 3.38 hrs HW=670.42' (Free Discharge)
1=Sand Filter (Custom Controls 0.05 cfs)
2=CP-Bleeder (Orifice Controls 0.44 cfs @ 8.87 fps)
3=Orifice/Grate (Weir Controls 3.67 cfs @ 1.35 fps)
L4=Culvert (Passes 3.67 cfs of 6.24 cfs potential flow)

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 6-hr 25-yr Rainfall=4.38"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 21
I
A
Pond 2A: Sand Filter
Hydrograph
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105 110 115 120
Time (hours)
L Inflow
❑ Primary

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 6-hr 25-yr Rainfall=4.38"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 22
Hydrograph for Pond 2A: Sand Filter
Time
Inflow
Storage
Elevation
Primary
(hours)
(cfs)
(cubic -feet)
(feet)
(cfs)
0.00
0.00
0
666.00
0.00
4.00
1.22
15,116
670.31
1.30
8.00
0.00
11,614
669.53
0.42
12.00
0.00
6,520
668.22
0.29
16.00
0.00
3,435
667.27
0.14
20.00
0.00
2,517
666.96
0.02
24.00
0.00
2,290
666.88
0.01
28.00
0.00
2,118
666.82
0.01
32.00
0.00
1,959
666.76
0.01
36.00
0.00
1,811
666.71
0.01
40.00
0.00
1,673
666.66
0.01
44.00
0.00
1,546
666.61
0.01
48.00
0.00
1,427
666.57
0.01
52.00
0.00
1,317
666.52
0.01
56.00
0.00
1,215
666.49
0.01
60.00
0.00
1,121
666.45
0.01
64.00
0.00
1,034
666.42
0.01
68.00
0.00
953
666.38
0.01
72.00
0.00
879
666.36
0.00
76.00
0.00
810
666.33
0.00
80.00
0.00
746
666.30
0.00
84.00
0.00
687
666.28
0.00
88.00
0.00
633
666.26
0.00
92.00
0.00
583
666.24
0.00
96.00
0.00
537
666.22
0.00
100.00
0.00
494
666.20
0.00
104.00
0.00
455
666.19
0.00
108.00
0.00
419
666.17
0.00
112.00
0.00
385
666.16
0.00
116.00
0.00
354
666.15
0.00
120.00
0.00
326
666.13
0.00

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 6-hr 25-yr Rainfall=4.38"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 23
Elevation Primary
(feet)
(cfs)
666.00
0.00
666.04
0.00
666.08
0.00
666.12
0.00
666.16
0.00
666.20
0.00
666.24
0.00
666.28
0.00
666.32
0.00
666.36
0.01
666.40
0.01
666.44
0.01
666.48
0.01
666.52
0.01
666.56
0.01
666.60
0.01
666.64
0.01
666.68
0.01
666.72
0.01
666.76
0.01
666.80
0.01
666.84
0.01
666.88
0.01
666.92
0.01
666.96
0.02
667.00
0.03
667.04
0.05
667.08
0.07
667.12
0.09
667.16
0.10
667.20
0.12
667.24
0.13
667.28
0.14
667.32
0.15
667.36
0.16
667.40
0.16
667.44
0.17
667.48
0.18
667.52
0.19
667.56
0.20
667.60
0.20
667.64
0.21
667.68
0.22
667.72
0.22
667.76
0.23
667.80
0.23
667.84
0.24
667.88
0.25
667.92
0.25
667.96
0.26
668.00
0.26
Stage -Discharge for Pond 2A: Sand Filter
Elevation Primary
(feet)
(cfs)
668.04
0.27
668.08
0.27
668.12
0.28
668.16
0.28
668.20
0.29
668.24
0.29
668.28
0.30
668.32
0.30
668.36
0.30
668.40
0.31
668.44
0.31
668.48
0.32
668.52
0.32
668.56
0.33
668.60
0.33
668.64
0.33
668.68
0.34
668.72
0.34
668.76
0.35
668.80
0.35
668.84
0.35
668.88
0.36
668.92
0.36
668.96
0.37
669.00
0.37
669.04
0.37
669.08
0.38
669.12
0.38
669.16
0.38
669.20
0.39
669.24
0.39
669.28
0.39
669.32
0.40
669.36
0.40
669.40
0.40
669.44
0.41
669.48
0.41
669.52
0.41
669.56
0.42
669.60
0.42
669.64
0.42
669.68
0.43
669.72
0.43
669.76
0.43
669.80
0.44
669.84
0.44
669.88
0.44
669.92
0.45
669.96
0.45
670.00
0.45
670.04
0.46
Elevation Primary
(feet)
(cfs)
670.08
0.46
670.12
0.46
670.16
0.46
670.20
0.47
670.24
0.47
670.28
0.75
670.32
1.45
670.36
2.39
670.40
3.52
670.44
4.82
670.48
6.26
670.52
7.83
670.56
8.92
670.60
9.45
670.64
9.95
670.68
10.42
670.72
10.88
670.76
11.31
670.80
11.73
670.84
12.13
670.88
12.52
670.92
12.90
670.96
13.27
671.00
13.62
671.04
13.97
671.08
14.31
671.12
14.64
671.16
14.96
671.20
15.28
671.24
15.59
671.28
15.89
671.32
16.19
671.36
16.48
671.40
16.77
671.44
17.05
671.48
17.33
671.52
17.61
671.56
17.87
671.60
18.14
671.64
18.40
671.68
18.66
671.72
18.91
671.76
19.16
671.80
19.41
671.84
19.65
671.88
19.89
671.92
20.13
671.96
20.37
672.00
20.60
672.04
20.83
672.08
21.06
Elevation Primary
(feet)
(cfs)
672.12
21.28
672.16
21.50
672.20
21.72
672.24
21.94
672.28
22.16
672.32
22.37
672.36
22.58
672.40
22.79
672.44
23.00
672.48
23.21
672.52
23.41
672.56
23.61
672.60
23.81
672.64
24.01
672.68
24.21
672.72
24.40
672.76
24.60
672.80
24.79
672.84
24.98
672.88
25.17
672.92
25.36
672.96
25.55
673.00
25.73
673.04
25.92
673.08
26.10
673.12
26.28
673.16
26.46
673.20
26.64
673.24
26.82
673.28
26.99
673.32
27.17
673.36
27.34
673.40
27.52
673.44
27.69
673.48
27.86

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 6-hr 25-yr Rainfall=4.38"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 24
Stage -Area -Storage for Pond 2A: Sand Filter
Elevation
Surface
Storage
(feet)
(sq-ft)
(cubic -feet)
666.00
2,385
0
666.10
2,432
241
666.20
2,480
487
666.30
2,529
737
666.40
2,578
992
666.50
2,627
1,253
666.60
2,677
1,518
666.70
2,727
1,788
666.80
2,778
2,063
666.90
2,829
2,344
667.00
2,881
2,629
667.10
2,931
2,920
667.20
2,982
3,215
667.30
3,033
3,516
667.40
3,085
3,822
667.50
3,137
4,133
667.60
3,190
4,449
667.70
3,243
4,771
667.80
3,296
5,098
667.90
3,350
5,430
668.00
3,404
5,768
668.10
3,457
6,111
668.20
3,511
6,459
668.30
3,565
6,813
668.40
3,620
7,173
668.50
3,675
7,537
668.60
3,730
7,907
668.70
3,786
8,283
668.80
3,842
8,665
668.90
3,899
9,052
669.00
3,956
9,445
669.10
4,012
9,843
669.20
4,069
10,247
669.30
4,126
10,657
669.40
4,183
11,072
669.50
4,241
11,493
669.60
4,299
11,920
669.70
4,358
12,353
669.80
4,417
12,792
669.90
4,476
13,237
670.00
4,536
13,687
670.10
4,612
14,145
670.20
4,689
14,610
670.30
4,767
15,082
670.40
4,845
15,563
670.50
4,924
16,052
670.60
5,004
16,548
670.70
5,084
17,052
670.80
5,165
17,565
670.90
5,246
18,085
671.00
5,328
18,614
Elevation
Surface
Storage
(feet)
(sq-ft)
(cubic -feet)
671.10
5,413
19,151
671.20
5,498
19,696
671.30
5,584
20,250
671.40
5,670
20,813
671.50
5,757
21,385
671.60
5,845
21,965
671.70
5,934
22,554
671.80
6,023
23,151
671.90
6,113
23,758
672.00
6,203
24,374
672.10
6,294
24,999
672.20
6,386
25,633
672.30
6,478
26,276
672.40
6,571
26,928
672.50
6,664
27,590
672.60
6,758
28,261
672.70
6,853
28,942
672.80
6,949
29,632
672.90
7,045
30,331
673.00
7,142
31,041
673.10
7,239
31,760
673.20
7,337
32,489
673.30
7,436
33,227
673.40
7,535
33,976
673.50
7,635
34,734

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 6-hr 25-yr Rainfall=4.38"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 25
Summary for Link 4: Post Total
Inflow Area = 191,882 sf, Inflow Depth > 2.38" for 25-yr event
Inflow = 8.08 cfs @ 3.35 hrs, Volume= 38,114 cf
Primary = 8.08 cfs @ 3.35 hrs, Volume= 38,114 cf, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
❑ Inflow
❑ Primary
N
U
3
0
LL

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 6-hr 25-yr Rainfall=4.38"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 26
Hydrograph for Link 4: Post Total
Time
Inflow
Elevation
Primary
(hours)
(cfs)
(feet)
(cfs)
0.00
0.00
0.00
0.00
2.00
0.00
0.00
0.00
4.00
2.16
0.00
2.16
6.00
0.73
0.00
0.73
8.00
0.42
0.00
0.42
10.00
0.35
0.00
0.35
12.00
0.29
0.00
0.29
14.00
0.22
0.00
0.22
16.00
0.14
0.00
0.14
18.00
0.05
0.00
0.05
20.00
0.02
0.00
0.02
22.00
0.01
0.00
0.01
24.00
0.01
0.00
0.01
26.00
0.01
0.00
0.01
28.00
0.01
0.00
0.01
30.00
0.01
0.00
0.01
32.00
0.01
0.00
0.01
34.00
0.01
0.00
0.01
36.00
0.01
0.00
0.01
38.00
0.01
0.00
0.01
40.00
0.01
0.00
0.01
42.00
0.01
0.00
0.01
44.00
0.01
0.00
0.01
46.00
0.01
0.00
0.01
48.00
0.01
0.00
0.01
50.00
0.01
0.00
0.01
52.00
0.01
0.00
0.01
54.00
0.01
0.00
0.01
56.00
0.01
0.00
0.01
58.00
0.01
0.00
0.01
60.00
0.01
0.00
0.01
62.00
0.01
0.00
0.01
64.00
0.01
0.00
0.01
66.00
0.01
0.00
0.01
68.00
0.01
0.00
0.01
70.00
0.01
0.00
0.01
72.00
0.00
0.00
0.00
74.00
0.00
0.00
0.00
76.00
0.00
0.00
0.00
78.00
0.00
0.00
0.00
80.00
0.00
0.00
0.00
82.00
0.00
0.00
0.00
84.00
0.00
0.00
0.00
86.00
0.00
0.00
0.00
88.00
0.00
0.00
0.00
90.00
0.00
0.00
0.00
92.00
0.00
0.00
0.00
94.00
0.00
0.00
0.00
96.00
0.00
0.00
0.00
98.00
0.00
0.00
0.00
100.00
0.00
0.00
0.00
Time
Inflow
Elevation
Primary
(hours)
(cfs)
(feet)
(cfs)
102.00
0.00
0.00
0.00
104.00
0.00
0.00
0.00
106.00
0.00
0.00
0.00
108.00
0.00
0.00
0.00
110.00
0.00
0.00
0.00
112.00
0.00
0.00
0.00
114.00
0.00
0.00
0.00
116.00
0.00
0.00
0.00
118.00
0.00
0.00
0.00
120.00
0.00
0.00
0.00

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 6-hr 50-yr Rainfall=4.92"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 27
Time span=0.00-120.00 hrs, dt=0.02 hrs, 6001 points
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN
Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method
Subcatchment 2: Post -Detained Runoff Area=2.254 ac Runoff Depth=3.70"
Tc=5.0 min CN=89 Runoff=15.64 cfs 30,236 cf
Subcatchment 3: Post-Undetained Runoff Area=2.151 ac Runoff Depth=1.98"
Tc=10.0 min CN=70 Runoff=7.06 cfs 15,438 cf
Pond 2A: Sand Filter Peak Elev=670.52' Storage=16,131 cf Inflow=15.64 cfs 30,236 cf
Outflow=7.48 cfs 29,909 cf
Link 4: Post Total Inflow=13.87 cfs 45,347 cf
Primary=13.87 cfs 45,347 cf
Total Runoff Area = 191,882 sf Runoff Volume = 45,674 cf Average Runoff Depth = 2.86"

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 6-hr 50-yr Rainfall=4.92"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 28
Summary for Subcatchment 2: Post -Detained
Runoff = 15.64 cfs @ 3.15 hrs, Volume= 30,236 cf, Depth= 3.70"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 50-yr Rainfall=4.92"
Area (ac) CN Description
1.624 88 Post -Development Detained Areas
0.370 88 Post -Development Detained Areas
0.260 98 Roofs, HSG B
2.254 89 Weighted Average
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry, Post -Detained
6 1
U
3
0
LL
Subcatchment 2: Post -Detained
Hydrograph
Time (hours)
■ Runoff

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 6-hr 50-yr Rainfall=4.92"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 29
Hydrograph for Subcatchment 2: Post -Detained
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
0.00
0.00
0.00
0.00
2.00
0.55
0.06
0.33
4.00
4.32
3.13
1.41
6.00
4.92
3.70
0.42
8.00
4.92
3.70
0.00
10.00
4.92
3.70
0.00
12.00
4.92
3.70
0.00
14.00
4.92
3.70
0.00
16.00
4.92
3.70
0.00
18.00
4.92
3.70
0.00
20.00
4.92
3.70
0.00
22.00
4.92
3.70
0.00
24.00
4.92
3.70
0.00
26.00
4.92
3.70
0.00
28.00
4.92
3.70
0.00
30.00
4.92
3.70
0.00
32.00
4.92
3.70
0.00
34.00
4.92
3.70
0.00
36.00
4.92
3.70
0.00
38.00
4.92
3.70
0.00
40.00
4.92
3.70
0.00
42.00
4.92
3.70
0.00
44.00
4.92
3.70
0.00
46.00
4.92
3.70
0.00
48.00
4.92
3.70
0.00
50.00
4.92
3.70
0.00
52.00
4.92
3.70
0.00
54.00
4.92
3.70
0.00
56.00
4.92
3.70
0.00
58.00
4.92
3.70
0.00
60.00
4.92
3.70
0.00
62.00
4.92
3.70
0.00
64.00
4.92
3.70
0.00
66.00
4.92
3.70
0.00
68.00
4.92
3.70
0.00
70.00
4.92
3.70
0.00
72.00
4.92
3.70
0.00
74.00
4.92
3.70
0.00
76.00
4.92
3.70
0.00
78.00
4.92
3.70
0.00
80.00
4.92
3.70
0.00
82.00
4.92
3.70
0.00
84.00
4.92
3.70
0.00
86.00
4.92
3.70
0.00
88.00
4.92
3.70
0.00
90.00
4.92
3.70
0.00
92.00
4.92
3.70
0.00
94.00
4.92
3.70
0.00
96.00
4.92
3.70
0.00
98.00
4.92
3.70
0.00
100.00
4.92
3.70
0.00
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
102.00
4.92
3.70
0.00
104.00
4.92
3.70
0.00
106.00
4.92
3.70
0.00
108.00
4.92
3.70
0.00
110.00
4.92
3.70
0.00
112.00
4.92
3.70
0.00
114.00
4.92
3.70
0.00
116.00
4.92
3.70
0.00
118.00
4.92
3.70
0.00
120.00
4.92
3.70
0.00

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 6-hr 50-yr Rainfall=4.92"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 30
Summary for Subcatchment 3: Post-Undetained
Runoff = 7.06 cfs @ 3.23 hrs, Volume= 15,438 cf, Depth= 1.98"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 50-yr Rainfall=4.92"
Area (ac) CN Description
2.151 70 Post -Development Undetained Areas
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
10.0 Direct Entry, Post-Undetained
■ Runoff
N
U
3
0
LL

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 6-hr 50-yr Rainfall=4.92"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 31
Hydrograph for Subcatchment 3: Post-Undetained
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
0.00
0.00
0.00
0.00
2.00
0.55
0.00
0.00
4.00
4.32
1.55
1.05
6.00
4.92
1.98
0.32
8.00
4.92
1.98
0.00
10.00
4.92
1.98
0.00
12.00
4.92
1.98
0.00
14.00
4.92
1.98
0.00
16.00
4.92
1.98
0.00
18.00
4.92
1.98
0.00
20.00
4.92
1.98
0.00
22.00
4.92
1.98
0.00
24.00
4.92
1.98
0.00
26.00
4.92
1.98
0.00
28.00
4.92
1.98
0.00
30.00
4.92
1.98
0.00
32.00
4.92
1.98
0.00
34.00
4.92
1.98
0.00
36.00
4.92
1.98
0.00
38.00
4.92
1.98
0.00
40.00
4.92
1.98
0.00
42.00
4.92
1.98
0.00
44.00
4.92
1.98
0.00
46.00
4.92
1.98
0.00
48.00
4.92
1.98
0.00
50.00
4.92
1.98
0.00
52.00
4.92
1.98
0.00
54.00
4.92
1.98
0.00
56.00
4.92
1.98
0.00
58.00
4.92
1.98
0.00
60.00
4.92
1.98
0.00
62.00
4.92
1.98
0.00
64.00
4.92
1.98
0.00
66.00
4.92
1.98
0.00
68.00
4.92
1.98
0.00
70.00
4.92
1.98
0.00
72.00
4.92
1.98
0.00
74.00
4.92
1.98
0.00
76.00
4.92
1.98
0.00
78.00
4.92
1.98
0.00
80.00
4.92
1.98
0.00
82.00
4.92
1.98
0.00
84.00
4.92
1.98
0.00
86.00
4.92
1.98
0.00
88.00
4.92
1.98
0.00
90.00
4.92
1.98
0.00
92.00
4.92
1.98
0.00
94.00
4.92
1.98
0.00
96.00
4.92
1.98
0.00
98.00
4.92
1.98
0.00
100.00
4.92
1.98
0.00
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
102.00
4.92
1.98
0.00
104.00
4.92
1.98
0.00
106.00
4.92
1.98
0.00
108.00
4.92
1.98
0.00
110.00
4.92
1.98
0.00
112.00
4.92
1.98
0.00
114.00
4.92
1.98
0.00
116.00
4.92
1.98
0.00
118.00
4.92
1.98
0.00
120.00
4.92
1.98
0.00

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 6-hr 50-yr Rainfall=4.92"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 32
Summary for Pond 2A: Sand Filter
Inflow Area =
98,184 sf,
Inflow Depth = 3.70"
for 50-yr event
Inflow =
15.64 cfs @
3.15 hrs, Volume=
30,236 cf
Outflow =
7.48 cfs @
3.29 hrs, Volume=
29,909 cf, Atten= 52%, Lag= 8.5 min
Primary =
7.48 cfs @
3.29 hrs, Volume=
29,909 cf
Routing by Stor-Ind method, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Peak Elev= 670.52' @ 3.29 hrs Surf.Area= 4,937 sf Storage= 16,131 cf
Plug -Flow detention time= 420.4 min calculated for 29,904 cf (99% of inflow)
Center -of -Mass det. time= 419.8 min (625.2 - 205.4 )
Volume Invert
Avail.Storage Storage Description
#1 666.00'
34,734 cf Sand Filter (Conic) Listed below (Recalc)
Elevation Surf.Area
Inc.Store Cum.Store
Wet.Area
(feet)
(sq-ft)
(cubic -feet) (cubic -feet)
(sq-ft)
666.00
2,385
0 0
2,385
667.00
2,881
2,629 2,629
2,913
668.00
3,404
3,139 5,768
3,473
669.00
3,956
3,677 9,445
4,065
670.00
4,536
4,243 13,687
4,689
671.00
5,328
4,927 18,614
5,519
672.00
6,203
5,760 24,374
6,435
673.00
7,142
6,667 31,041
7,417
673.50
7,635
3,694 34,734
7,933
Device Routing
Invert
Outlet Devices
#1 Primary
666.00'
Sand Filter
Elev. (feet) 666.00 667.00 668.00
669.00 670.00 671.00 672.00
673.00
Disch. (cfs) 0.000 0.014 0.029 0.037 0.045 0.053 0.061 0.069
#2 Primary
666.90'
3.0" Vert. CP-Bleeder C= 0.600
#3 Primary
670.25'
48.0" x 48.0" Horiz. Orifice/Grate
C= 0.600
Limited to weir flow at low heads
#4 Device 3
662.47'
24.0" Round Culvert
L= 93.8' RCP, square edge headwall, Ke= 0.500
Inlet / Outlet Invert= 662.47' / 662.00' S= 0.0050 '/' Cc= 0.900
n= 0.013, Flow Area= 3.14 sf
Primary OutFlow Max=7.59 cfs @ 3.29 hrs HW=670.51' (Free Discharge)
1=Sand Filter (Custom Controls 0.05 cfs)
2=CP-Bleeder (Orifice Controls 0.44 cfs @ 8.99 fps)
3=Orifice/Grate (Weir Controls 7.10 cfs @ 1.68 fps)
L4=Culvert (Passes 7.10 cfs of 7.77 cfs potential flow)

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 6-hr 50-yr Rainfall=4.92"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 33
Pond 2A: Sand Filter
Hydrograph
FL-1 n —fI o—w
❑ Primary
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105 110 115 120
Time (hours)

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 6-hr 50-yr Rainfall=4.92"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 34
Hydrograph for Pond 2A: Sand Filter
Time
Inflow
Storage
Elevation
Primary
(hours)
(cfs)
(cubic -feet)
(feet)
(cfs)
0.00
0.00
0
666.00
0.00
4.00
1.41
15,166
670.32
1.50
8.00
0.00
11,734
669.56
0.42
12.00
0.00
6,603
668.24
0.29
16.00
0.00
3,474
667.29
0.14
20.00
0.00
2,524
666.96
0.02
24.00
0.00
2,293
666.88
0.01
28.00
0.00
2,122
666.82
0.01
32.00
0.00
1,962
666.76
0.01
36.00
0.00
1,814
666.71
0.01
40.00
0.00
1,676
666.66
0.01
44.00
0.00
1,548
666.61
0.01
48.00
0.00
1,429
666.57
0.01
52.00
0.00
1,319
666.53
0.01
56.00
0.00
1,217
666.49
0.01
60.00
0.00
1,123
666.45
0.01
64.00
0.00
1,036
666.42
0.01
68.00
0.00
955
666.39
0.01
72.00
0.00
880
666.36
0.00
76.00
0.00
811
666.33
0.00
80.00
0.00
747
666.30
0.00
84.00
0.00
688
666.28
0.00
88.00
0.00
634
666.26
0.00
92.00
0.00
584
666.24
0.00
96.00
0.00
538
666.22
0.00
100.00
0.00
495
666.20
0.00
104.00
0.00
455
666.19
0.00
108.00
0.00
419
666.17
0.00
112.00
0.00
386
666.16
0.00
116.00
0.00
355
666.15
0.00
120.00
0.00
327
666.14
0.00

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 6-hr 50-yr Rainfall=4.92"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 35
Elevation Primary
(feet)
(cfs)
666.00
0.00
666.04
0.00
666.08
0.00
666.12
0.00
666.16
0.00
666.20
0.00
666.24
0.00
666.28
0.00
666.32
0.00
666.36
0.01
666.40
0.01
666.44
0.01
666.48
0.01
666.52
0.01
666.56
0.01
666.60
0.01
666.64
0.01
666.68
0.01
666.72
0.01
666.76
0.01
666.80
0.01
666.84
0.01
666.88
0.01
666.92
0.01
666.96
0.02
667.00
0.03
667.04
0.05
667.08
0.07
667.12
0.09
667.16
0.10
667.20
0.12
667.24
0.13
667.28
0.14
667.32
0.15
667.36
0.16
667.40
0.16
667.44
0.17
667.48
0.18
667.52
0.19
667.56
0.20
667.60
0.20
667.64
0.21
667.68
0.22
667.72
0.22
667.76
0.23
667.80
0.23
667.84
0.24
667.88
0.25
667.92
0.25
667.96
0.26
668.00
0.26
Stage -Discharge for Pond 2A: Sand Filter
Elevation Primary
(feet)
(cfs)
668.04
0.27
668.08
0.27
668.12
0.28
668.16
0.28
668.20
0.29
668.24
0.29
668.28
0.30
668.32
0.30
668.36
0.30
668.40
0.31
668.44
0.31
668.48
0.32
668.52
0.32
668.56
0.33
668.60
0.33
668.64
0.33
668.68
0.34
668.72
0.34
668.76
0.35
668.80
0.35
668.84
0.35
668.88
0.36
668.92
0.36
668.96
0.37
669.00
0.37
669.04
0.37
669.08
0.38
669.12
0.38
669.16
0.38
669.20
0.39
669.24
0.39
669.28
0.39
669.32
0.40
669.36
0.40
669.40
0.40
669.44
0.41
669.48
0.41
669.52
0.41
669.56
0.42
669.60
0.42
669.64
0.42
669.68
0.43
669.72
0.43
669.76
0.43
669.80
0.44
669.84
0.44
669.88
0.44
669.92
0.45
669.96
0.45
670.00
0.45
670.04
0.46
Elevation Primary
(feet)
(cfs)
670.08
0.46
670.12
0.46
670.16
0.46
670.20
0.47
670.24
0.47
670.28
0.75
670.32
1.45
670.36
2.39
670.40
3.52
670.44
4.82
670.48
6.26
670.52
7.83
670.56
8.92
670.60
9.45
670.64
9.95
670.68
10.42
670.72
10.88
670.76
11.31
670.80
11.73
670.84
12.13
670.88
12.52
670.92
12.90
670.96
13.27
671.00
13.62
671.04
13.97
671.08
14.31
671.12
14.64
671.16
14.96
671.20
15.28
671.24
15.59
671.28
15.89
671.32
16.19
671.36
16.48
671.40
16.77
671.44
17.05
671.48
17.33
671.52
17.61
671.56
17.87
671.60
18.14
671.64
18.40
671.68
18.66
671.72
18.91
671.76
19.16
671.80
19.41
671.84
19.65
671.88
19.89
671.92
20.13
671.96
20.37
672.00
20.60
672.04
20.83
672.08
21.06
Elevation Primary
(feet)
(cfs)
672.12
21.28
672.16
21.50
672.20
21.72
672.24
21.94
672.28
22.16
672.32
22.37
672.36
22.58
672.40
22.79
672.44
23.00
672.48
23.21
672.52
23.41
672.56
23.61
672.60
23.81
672.64
24.01
672.68
24.21
672.72
24.40
672.76
24.60
672.80
24.79
672.84
24.98
672.88
25.17
672.92
25.36
672.96
25.55
673.00
25.73
673.04
25.92
673.08
26.10
673.12
26.28
673.16
26.46
673.20
26.64
673.24
26.82
673.28
26.99
673.32
27.17
673.36
27.34
673.40
27.52
673.44
27.69
673.48
27.86

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 6-hr 50-yr Rainfall=4.92"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 36
Stage -Area -Storage for Pond 2A: Sand Filter
Elevation
Surface
Storage
(feet)
(sq-ft)
(cubic -feet)
666.00
2,385
0
666.10
2,432
241
666.20
2,480
487
666.30
2,529
737
666.40
2,578
992
666.50
2,627
1,253
666.60
2,677
1,518
666.70
2,727
1,788
666.80
2,778
2,063
666.90
2,829
2,344
667.00
2,881
2,629
667.10
2,931
2,920
667.20
2,982
3,215
667.30
3,033
3,516
667.40
3,085
3,822
667.50
3,137
4,133
667.60
3,190
4,449
667.70
3,243
4,771
667.80
3,296
5,098
667.90
3,350
5,430
668.00
3,404
5,768
668.10
3,457
6,111
668.20
3,511
6,459
668.30
3,565
6,813
668.40
3,620
7,173
668.50
3,675
7,537
668.60
3,730
7,907
668.70
3,786
8,283
668.80
3,842
8,665
668.90
3,899
9,052
669.00
3,956
9,445
669.10
4,012
9,843
669.20
4,069
10,247
669.30
4,126
10,657
669.40
4,183
11,072
669.50
4,241
11,493
669.60
4,299
11,920
669.70
4,358
12,353
669.80
4,417
12,792
669.90
4,476
13,237
670.00
4,536
13,687
670.10
4,612
14,145
670.20
4,689
14,610
670.30
4,767
15,082
670.40
4,845
15,563
670.50
4,924
16,052
670.60
5,004
16,548
670.70
5,084
17,052
670.80
5,165
17,565
670.90
5,246
18,085
671.00
5,328
18,614
Elevation
Surface
Storage
(feet)
(sq-ft)
(cubic -feet)
671.10
5,413
19,151
671.20
5,498
19,696
671.30
5,584
20,250
671.40
5,670
20,813
671.50
5,757
21,385
671.60
5,845
21,965
671.70
5,934
22,554
671.80
6,023
23,151
671.90
6,113
23,758
672.00
6,203
24,374
672.10
6,294
24,999
672.20
6,386
25,633
672.30
6,478
26,276
672.40
6,571
26,928
672.50
6,664
27,590
672.60
6,758
28,261
672.70
6,853
28,942
672.80
6,949
29,632
672.90
7,045
30,331
673.00
7,142
31,041
673.10
7,239
31,760
673.20
7,337
32,489
673.30
7,436
33,227
673.40
7,535
33,976
673.50
7,635
34,734

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 6-hr 50-yr Rainfall=4.92"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 37
Summary for Link 4: Post Total
Inflow Area = 191,882 sf, Inflow Depth > 2.84" for 50-yr event
Inflow = 13.87 cfs @ 3.27 hrs, Volume= 45,347 cf
Primary = 13.87 cfs @ 3.27 hrs, Volume= 45,347 cf, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
1
1
1
1
1
1
N
U
3
0
LL
Link 4: Post Total
Hydrograph
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105 110 115 120
Time (hours)
❑ Inflow
❑ Primary

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-19 Charlotte 6-hr 50-yr Rainfall=4.92"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 38
Hydrograph for Link 4: Post Total
Time
Inflow
Elevation
Primary
(hours)
(cfs)
(feet)
(cfs)
0.00
0.00
0.00
0.00
2.00
0.00
0.00
0.00
4.00
2.55
0.00
2.55
6.00
0.79
0.00
0.79
8.00
0.42
0.00
0.42
10.00
0.36
0.00
0.36
12.00
0.29
0.00
0.29
14.00
0.22
0.00
0.22
16.00
0.14
0.00
0.14
18.00
0.06
0.00
0.06
20.00
0.02
0.00
0.02
22.00
0.02
0.00
0.02
24.00
0.01
0.00
0.01
26.00
0.01
0.00
0.01
28.00
0.01
0.00
0.01
30.00
0.01
0.00
0.01
32.00
0.01
0.00
0.01
34.00
0.01
0.00
0.01
36.00
0.01
0.00
0.01
38.00
0.01
0.00
0.01
40.00
0.01
0.00
0.01
42.00
0.01
0.00
0.01
44.00
0.01
0.00
0.01
46.00
0.01
0.00
0.01
48.00
0.01
0.00
0.01
50.00
0.01
0.00
0.01
52.00
0.01
0.00
0.01
54.00
0.01
0.00
0.01
56.00
0.01
0.00
0.01
58.00
0.01
0.00
0.01
60.00
0.01
0.00
0.01
62.00
0.01
0.00
0.01
64.00
0.01
0.00
0.01
66.00
0.01
0.00
0.01
68.00
0.01
0.00
0.01
70.00
0.01
0.00
0.01
72.00
0.00
0.00
0.00
74.00
0.00
0.00
0.00
76.00
0.00
0.00
0.00
78.00
0.00
0.00
0.00
80.00
0.00
0.00
0.00
82.00
0.00
0.00
0.00
84.00
0.00
0.00
0.00
86.00
0.00
0.00
0.00
88.00
0.00
0.00
0.00
90.00
0.00
0.00
0.00
92.00
0.00
0.00
0.00
94.00
0.00
0.00
0.00
96.00
0.00
0.00
0.00
98.00
0.00
0.00
0.00
100.00
0.00
0.00
0.00
Time
Inflow
Elevation
Primary
(hours)
(cfs)
(feet)
(cfs)
102.00
0.00
0.00
0.00
104.00
0.00
0.00
0.00
106.00
0.00
0.00
0.00
108.00
0.00
0.00
0.00
110.00
0.00
0.00
0.00
112.00
0.00
0.00
0.00
114.00
0.00
0.00
0.00
116.00
0.00
0.00
0.00
118.00
0.00
0.00
0.00
120.00
0.00
0.00
0.00

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-1 Charlotte 6-hr 100-yr Rainfall=5.34"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 39
Time span=0.00-120.00 hrs, dt=0.02 hrs, 6001 points
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN
Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method
Subcatchment 2: Post -Detained Runoff Area=2.254 ac Runoff Depth=4.10"
Tc=5.0 min CN=89 Runoff=17.52 cfs 33,532 cf
Subcatchment 3: Post-Undetained Runoff Area=2.151 ac Runoff Depth=2.29"
Tc=10.0 min CN=70 Runoff=8.33 cfs 17,895 cf
Pond 2A: Sand Filter Peak Elev=670.62' Storage=16,655 cf Inflow=17.52 cfs 33,532 cf
Outflow=9.70 cfs 33,205 cf
Link 4: Post Total Inflow=17.83 cfs 51,100 cf
Primary=17.83 cfs 51,100 cf
Total Runoff Area = 191,882 sf Runoff Volume = 51,427 cf Average Runoff Depth = 3.22"

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-1 Charlotte 6-hr 100-yr Rainfall=5.34"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 40
Summary for Subcatchment 2: Post -Detained
Runoff = 17.52 cfs @ 3.15 hrs, Volume= 33,532 cf, Depth= 4.10"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 100-yr Rainfall=5.34"
Area (ac) CN Description
1.624 88 Post -Development Detained Areas
0.370 88 Post -Development Detained Areas
0.260 98 Roofs, HSG B
2.254 89 Weighted Average
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry, Post -Detained
Subcatchment 2: Post -Detained
Hydrograph
■ Runoff
Time (hours)

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-1 Charlotte 6-hr 100-yr Rainfall=5.34"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 41
Hydrograph for Subcatchment 2: Post -Detained
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
0.00
0.00
0.00
0.00
2.00
0.59
0.07
0.38
4.00
4.70
3.49
1.51
6.00
5.34
4.10
0.47
8.00
5.34
4.10
0.00
10.00
5.34
4.10
0.00
12.00
5.34
4.10
0.00
14.00
5.34
4.10
0.00
16.00
5.34
4.10
0.00
18.00
5.34
4.10
0.00
20.00
5.34
4.10
0.00
22.00
5.34
4.10
0.00
24.00
5.34
4.10
0.00
26.00
5.34
4.10
0.00
28.00
5.34
4.10
0.00
30.00
5.34
4.10
0.00
32.00
5.34
4.10
0.00
34.00
5.34
4.10
0.00
36.00
5.34
4.10
0.00
38.00
5.34
4.10
0.00
40.00
5.34
4.10
0.00
42.00
5.34
4.10
0.00
44.00
5.34
4.10
0.00
46.00
5.34
4.10
0.00
48.00
5.34
4.10
0.00
50.00
5.34
4.10
0.00
52.00
5.34
4.10
0.00
54.00
5.34
4.10
0.00
56.00
5.34
4.10
0.00
58.00
5.34
4.10
0.00
60.00
5.34
4.10
0.00
62.00
5.34
4.10
0.00
64.00
5.34
4.10
0.00
66.00
5.34
4.10
0.00
68.00
5.34
4.10
0.00
70.00
5.34
4.10
0.00
72.00
5.34
4.10
0.00
74.00
5.34
4.10
0.00
76.00
5.34
4.10
0.00
78.00
5.34
4.10
0.00
80.00
5.34
4.10
0.00
82.00
5.34
4.10
0.00
84.00
5.34
4.10
0.00
86.00
5.34
4.10
0.00
88.00
5.34
4.10
0.00
90.00
5.34
4.10
0.00
92.00
5.34
4.10
0.00
94.00
5.34
4.10
0.00
96.00
5.34
4.10
0.00
98.00
5.34
4.10
0.00
100.00
5.34
4.10
0.00
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
102.00
5.34
4.10
0.00
104.00
5.34
4.10
0.00
106.00
5.34
4.10
0.00
108.00
5.34
4.10
0.00
110.00
5.34
4.10
0.00
112.00
5.34
4.10
0.00
114.00
5.34
4.10
0.00
116.00
5.34
4.10
0.00
118.00
5.34
4.10
0.00
120.00
5.34
4.10
0.00

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-1 Charlotte 6-hr 100-yr Rainfall=5.34"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 42
Summary for Subcatchment 3: Post-Undetained
Runoff = 8.33 cfs @ 3.23 hrs, Volume= 17,895 cf, Depth= 2.29"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 100-yr Rainfall=5.34"
Area (ac) CN Description
2.151 70 Post -Development Undetained Areas
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
10.0 Direct Entry, Post-Undetained
■ Runoff
N
U
3
0
LL

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-1 Charlotte 6-hr 100-yr Rainfall=5.34"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 43
Hydrograph for Subcatchment 3: Post-Undetained
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
0.00
0.00
0.00
0.00
2.00
0.59
0.00
0.00
4.00
4.70
1.82
1.16
6.00
5.34
2.29
0.36
8.00
5.34
2.29
0.00
10.00
5.34
2.29
0.00
12.00
5.34
2.29
0.00
14.00
5.34
2.29
0.00
16.00
5.34
2.29
0.00
18.00
5.34
2.29
0.00
20.00
5.34
2.29
0.00
22.00
5.34
2.29
0.00
24.00
5.34
2.29
0.00
26.00
5.34
2.29
0.00
28.00
5.34
2.29
0.00
30.00
5.34
2.29
0.00
32.00
5.34
2.29
0.00
34.00
5.34
2.29
0.00
36.00
5.34
2.29
0.00
38.00
5.34
2.29
0.00
40.00
5.34
2.29
0.00
42.00
5.34
2.29
0.00
44.00
5.34
2.29
0.00
46.00
5.34
2.29
0.00
48.00
5.34
2.29
0.00
50.00
5.34
2.29
0.00
52.00
5.34
2.29
0.00
54.00
5.34
2.29
0.00
56.00
5.34
2.29
0.00
58.00
5.34
2.29
0.00
60.00
5.34
2.29
0.00
62.00
5.34
2.29
0.00
64.00
5.34
2.29
0.00
66.00
5.34
2.29
0.00
68.00
5.34
2.29
0.00
70.00
5.34
2.29
0.00
72.00
5.34
2.29
0.00
74.00
5.34
2.29
0.00
76.00
5.34
2.29
0.00
78.00
5.34
2.29
0.00
80.00
5.34
2.29
0.00
82.00
5.34
2.29
0.00
84.00
5.34
2.29
0.00
86.00
5.34
2.29
0.00
88.00
5.34
2.29
0.00
90.00
5.34
2.29
0.00
92.00
5.34
2.29
0.00
94.00
5.34
2.29
0.00
96.00
5.34
2.29
0.00
98.00
5.34
2.29
0.00
100.00
5.34
2.29
0.00
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
102.00
5.34
2.29
0.00
104.00
5.34
2.29
0.00
106.00
5.34
2.29
0.00
108.00
5.34
2.29
0.00
110.00
5.34
2.29
0.00
112.00
5.34
2.29
0.00
114.00
5.34
2.29
0.00
116.00
5.34
2.29
0.00
118.00
5.34
2.29
0.00
120.00
5.34
2.29
0.00

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-1 Charlotte 6-hr 100-yr Rainfall=5.34"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 44
Summary for Pond 2A: Sand Filter
Inflow Area =
98,184 sf,
Inflow Depth = 4.10"
for 100-yr event
Inflow =
17.52 cfs @
3.15 hrs, Volume=
33,532 cf
Outflow =
9.70 cfs @
3.26 hrs, Volume=
33,205 cf, Atten= 45%, Lag= 6.9 min
Primary =
9.70 cfs @
3.26 hrs, Volume=
33,205 cf
Routing by Stor-Ind method, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
Peak Elev= 670.62' @ 3.26 hrs Surf.Area= 5,021 sf Storage= 16,655 cf
Plug -Flow detention time= 381.6 min calculated for 33,205 cf (99% of inflow)
Center -of -Mass det. time= 380.1 min ( 584.7 - 204.6 )
Volume Invert
Avail.Storage Storage Description
#1 666.00'
34,734 cf Sand Filter (Conic) Listed below (Recalc)
Elevation Surf.Area
Inc.Store Cum.Store
Wet.Area
(feet)
(sq-ft)
(cubic -feet) (cubic -feet)
(sq-ft)
666.00
2,385
0 0
2,385
667.00
2,881
2,629 2,629
2,913
668.00
3,404
3,139 5,768
3,473
669.00
3,956
3,677 9,445
4,065
670.00
4,536
4,243 13,687
4,689
671.00
5,328
4,927 18,614
5,519
672.00
6,203
5,760 24,374
6,435
673.00
7,142
6,667 31,041
7,417
673.50
7,635
3,694 34,734
7,933
Device Routing
Invert
Outlet Devices
#1 Primary
666.00'
Sand Filter
Elev. (feet) 666.00 667.00 668.00
669.00 670.00 671.00 672.00
673.00
Disch. (cfs) 0.000 0.014 0.029 0.037 0.045 0.053 0.061 0.069
#2 Primary
666.90'
3.0" Vert. CP-Bleeder C= 0.600
#3 Primary
670.25'
48.0" x 48.0" Horiz. Orifice/Grate
C= 0.600
Limited to weir flow at low heads
#4 Device 3
662.47'
24.0" Round Culvert
L= 93.8' RCP, square edge headwall, Ke= 0.500
Inlet / Outlet Invert= 662.47' / 662.00' S= 0.0050 '/' Cc= 0.900
n= 0.013, Flow Area= 3.14 sf
Primary OutFlow Max=9.70 cfs @ 3.26 hrs HW=670.62' (Free Discharge)
1=Sand Filter (Custom Controls 0.05 cfs)
2=CP-Bleeder (Orifice Controls 0.45 cfs @ 9.13 fps)
3=Orifice/Grate (Passes 9.21 cfs of 11.79 cfs potential flow)
L4=Culvert (Inlet Controls 9.21 cfs @ 2.93 fps)

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-1 Charlotte 6-hr 100-yr Rainfall=5.34"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 45
Pond 2A: Sand Filter
Hydrograph
FL-1 n —fI o—w
❑ Primary
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105 110 115 120
Time (hours)

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-1 Charlotte 6-hr 100-yr Rainfall=5.34"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 46
Hydrograph for Pond 2A: Sand Filter
Time
Inflow
Storage
Elevation
Primary
(hours)
(cfs)
(cubic -feet)
(feet)
(cfs)
0.00
0.00
0
666.00
0.00
4.00
1.51
15,193
670.32
1.61
8.00
0.00
11,769
669.56
0.42
12.00
0.00
6,628
668.25
0.29
16.00
0.00
3,486
667.29
0.14
20.00
0.00
2,526
666.96
0.02
24.00
0.00
2,294
666.88
0.01
28.00
0.00
2,123
666.82
0.01
32.00
0.00
1,963
666.76
0.01
36.00
0.00
1,815
666.71
0.01
40.00
0.00
1,677
666.66
0.01
44.00
0.00
1,549
666.61
0.01
48.00
0.00
1,430
666.57
0.01
52.00
0.00
1,320
666.53
0.01
56.00
0.00
1,218
666.49
0.01
60.00
0.00
1,123
666.45
0.01
64.00
0.00
1,036
666.42
0.01
68.00
0.00
955
666.39
0.01
72.00
0.00
880
666.36
0.00
76.00
0.00
811
666.33
0.00
80.00
0.00
748
666.30
0.00
84.00
0.00
689
666.28
0.00
88.00
0.00
634
666.26
0.00
92.00
0.00
584
666.24
0.00
96.00
0.00
538
666.22
0.00
100.00
0.00
495
666.20
0.00
104.00
0.00
456
666.19
0.00
108.00
0.00
419
666.17
0.00
112.00
0.00
386
666.16
0.00
116.00
0.00
355
666.15
0.00
120.00
0.00
327
666.14
0.00

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-1 Charlotte 6-hr 100-yr Rainfall=5.34"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 47
Elevation Primary
(feet)
(cfs)
666.00
0.00
666.04
0.00
666.08
0.00
666.12
0.00
666.16
0.00
666.20
0.00
666.24
0.00
666.28
0.00
666.32
0.00
666.36
0.01
666.40
0.01
666.44
0.01
666.48
0.01
666.52
0.01
666.56
0.01
666.60
0.01
666.64
0.01
666.68
0.01
666.72
0.01
666.76
0.01
666.80
0.01
666.84
0.01
666.88
0.01
666.92
0.01
666.96
0.02
667.00
0.03
667.04
0.05
667.08
0.07
667.12
0.09
667.16
0.10
667.20
0.12
667.24
0.13
667.28
0.14
667.32
0.15
667.36
0.16
667.40
0.16
667.44
0.17
667.48
0.18
667.52
0.19
667.56
0.20
667.60
0.20
667.64
0.21
667.68
0.22
667.72
0.22
667.76
0.23
667.80
0.23
667.84
0.24
667.88
0.25
667.92
0.25
667.96
0.26
668.00
0.26
Stage -Discharge for Pond 2A: Sand Filter
Elevation Primary
(feet)
(cfs)
668.04
0.27
668.08
0.27
668.12
0.28
668.16
0.28
668.20
0.29
668.24
0.29
668.28
0.30
668.32
0.30
668.36
0.30
668.40
0.31
668.44
0.31
668.48
0.32
668.52
0.32
668.56
0.33
668.60
0.33
668.64
0.33
668.68
0.34
668.72
0.34
668.76
0.35
668.80
0.35
668.84
0.35
668.88
0.36
668.92
0.36
668.96
0.37
669.00
0.37
669.04
0.37
669.08
0.38
669.12
0.38
669.16
0.38
669.20
0.39
669.24
0.39
669.28
0.39
669.32
0.40
669.36
0.40
669.40
0.40
669.44
0.41
669.48
0.41
669.52
0.41
669.56
0.42
669.60
0.42
669.64
0.42
669.68
0.43
669.72
0.43
669.76
0.43
669.80
0.44
669.84
0.44
669.88
0.44
669.92
0.45
669.96
0.45
670.00
0.45
670.04
0.46
Elevation Primary
(feet)
(cfs)
670.08
0.46
670.12
0.46
670.16
0.46
670.20
0.47
670.24
0.47
670.28
0.75
670.32
1.45
670.36
2.39
670.40
3.52
670.44
4.82
670.48
6.26
670.52
7.83
670.56
8.92
670.60
9.45
670.64
9.95
670.68
10.42
670.72
10.88
670.76
11.31
670.80
11.73
670.84
12.13
670.88
12.52
670.92
12.90
670.96
13.27
671.00
13.62
671.04
13.97
671.08
14.31
671.12
14.64
671.16
14.96
671.20
15.28
671.24
15.59
671.28
15.89
671.32
16.19
671.36
16.48
671.40
16.77
671.44
17.05
671.48
17.33
671.52
17.61
671.56
17.87
671.60
18.14
671.64
18.40
671.68
18.66
671.72
18.91
671.76
19.16
671.80
19.41
671.84
19.65
671.88
19.89
671.92
20.13
671.96
20.37
672.00
20.60
672.04
20.83
672.08
21.06
Elevation Primary
(feet)
(cfs)
672.12
21.28
672.16
21.50
672.20
21.72
672.24
21.94
672.28
22.16
672.32
22.37
672.36
22.58
672.40
22.79
672.44
23.00
672.48
23.21
672.52
23.41
672.56
23.61
672.60
23.81
672.64
24.01
672.68
24.21
672.72
24.40
672.76
24.60
672.80
24.79
672.84
24.98
672.88
25.17
672.92
25.36
672.96
25.55
673.00
25.73
673.04
25.92
673.08
26.10
673.12
26.28
673.16
26.46
673.20
26.64
673.24
26.82
673.28
26.99
673.32
27.17
673.36
27.34
673.40
27.52
673.44
27.69
673.48
27.86

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-1 Charlotte 6-hr 100-yr Rainfall=5.34"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 48
Stage -Area -Storage for Pond 2A: Sand Filter
Elevation
Surface
Storage
(feet)
(sq-ft)
(cubic -feet)
666.00
2,385
0
666.10
2,432
241
666.20
2,480
487
666.30
2,529
737
666.40
2,578
992
666.50
2,627
1,253
666.60
2,677
1,518
666.70
2,727
1,788
666.80
2,778
2,063
666.90
2,829
2,344
667.00
2,881
2,629
667.10
2,931
2,920
667.20
2,982
3,215
667.30
3,033
3,516
667.40
3,085
3,822
667.50
3,137
4,133
667.60
3,190
4,449
667.70
3,243
4,771
667.80
3,296
5,098
667.90
3,350
5,430
668.00
3,404
5,768
668.10
3,457
6,111
668.20
3,511
6,459
668.30
3,565
6,813
668.40
3,620
7,173
668.50
3,675
7,537
668.60
3,730
7,907
668.70
3,786
8,283
668.80
3,842
8,665
668.90
3,899
9,052
669.00
3,956
9,445
669.10
4,012
9,843
669.20
4,069
10,247
669.30
4,126
10,657
669.40
4,183
11,072
669.50
4,241
11,493
669.60
4,299
11,920
669.70
4,358
12,353
669.80
4,417
12,792
669.90
4,476
13,237
670.00
4,536
13,687
670.10
4,612
14,145
670.20
4,689
14,610
670.30
4,767
15,082
670.40
4,845
15,563
670.50
4,924
16,052
670.60
5,004
16,548
670.70
5,084
17,052
670.80
5,165
17,565
670.90
5,246
18,085
671.00
5,328
18,614
Elevation
Surface
Storage
(feet)
(sq-ft)
(cubic -feet)
671.10
5,413
19,151
671.20
5,498
19,696
671.30
5,584
20,250
671.40
5,670
20,813
671.50
5,757
21,385
671.60
5,845
21,965
671.70
5,934
22,554
671.80
6,023
23,151
671.90
6,113
23,758
672.00
6,203
24,374
672.10
6,294
24,999
672.20
6,386
25,633
672.30
6,478
26,276
672.40
6,571
26,928
672.50
6,664
27,590
672.60
6,758
28,261
672.70
6,853
28,942
672.80
6,949
29,632
672.90
7,045
30,331
673.00
7,142
31,041
673.10
7,239
31,760
673.20
7,337
32,489
673.30
7,436
33,227
673.40
7,535
33,976
673.50
7,635
34,734

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-1 Charlotte 6-hr 100-yr Rainfall=5.34"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 49
Summary for Link 4: Post Total
Inflow Area = 191,882 sf, Inflow Depth > 3.20" for 100-yr event
Inflow = 17.83 cfs @ 3.24 hrs, Volume= 51,100 cf
Primary = 17.83 cfs @ 3.24 hrs, Volume= 51,100 cf, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-120.00 hrs, dt= 0.02 hrs
1
1
1
1
1
1
1
1
w 1
U
3 1
0
LL
Link 4: Post Total
Hydrograph
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105 110 115 120
Time (hours)
❑ Inflow
❑ Primary

Skyland Drive 10-4-2019
Skyland Drive Townhomes_Sand Filter_BMP Rev 9-6-1 Charlotte 6-hr 100-yr Rainfall=5.34"
Prepared by {American Engineering Associates} Printed 10/4/2019
HydroCAD® 10.00-24 s/n 10674 © 2018 HydroCAD Software Solutions LLC Page 50
Hydrograph for Link 4: Post Total
Time
Inflow
Elevation
Primary
(hours)
(cfs)
(feet)
(cfs)
0.00
0.00
0.00
0.00
2.00
0.00
0.00
0.00
4.00
2.78
0.00
2.78
6.00
0.85
0.00
0.85
8.00
0.42
0.00
0.42
10.00
0.36
0.00
0.36
12.00
0.29
0.00
0.29
14.00
0.22
0.00
0.22
16.00
0.14
0.00
0.14
18.00
0.06
0.00
0.06
20.00
0.02
0.00
0.02
22.00
0.02
0.00
0.02
24.00
0.01
0.00
0.01
26.00
0.01
0.00
0.01
28.00
0.01
0.00
0.01
30.00
0.01
0.00
0.01
32.00
0.01
0.00
0.01
34.00
0.01
0.00
0.01
36.00
0.01
0.00
0.01
38.00
0.01
0.00
0.01
40.00
0.01
0.00
0.01
42.00
0.01
0.00
0.01
44.00
0.01
0.00
0.01
46.00
0.01
0.00
0.01
48.00
0.01
0.00
0.01
50.00
0.01
0.00
0.01
52.00
0.01
0.00
0.01
54.00
0.01
0.00
0.01
56.00
0.01
0.00
0.01
58.00
0.01
0.00
0.01
60.00
0.01
0.00
0.01
62.00
0.01
0.00
0.01
64.00
0.01
0.00
0.01
66.00
0.01
0.00
0.01
68.00
0.01
0.00
0.01
70.00
0.01
0.00
0.01
72.00
0.00
0.00
0.00
74.00
0.00
0.00
0.00
76.00
0.00
0.00
0.00
78.00
0.00
0.00
0.00
80.00
0.00
0.00
0.00
82.00
0.00
0.00
0.00
84.00
0.00
0.00
0.00
86.00
0.00
0.00
0.00
88.00
0.00
0.00
0.00
90.00
0.00
0.00
0.00
92.00
0.00
0.00
0.00
94.00
0.00
0.00
0.00
96.00
0.00
0.00
0.00
98.00
0.00
0.00
0.00
100.00
0.00
0.00
0.00
Time
Inflow
Elevation
Primary
(hours)
(cfs)
(feet)
(cfs)
102.00
0.00
0.00
0.00
104.00
0.00
0.00
0.00
106.00
0.00
0.00
0.00
108.00
0.00
0.00
0.00
110.00
0.00
0.00
0.00
112.00
0.00
0.00
0.00
114.00
0.00
0.00
0.00
116.00
0.00
0.00
0.00
118.00
0.00
0.00
0.00
120.00
0.00
0.00
0.00

EROSION AND SEDIMENT
CONTROL CALCULATIONS

SEDIMENT BASIN
(per NCDENR EROSION AND SEDIMENT CONTROL MANUAL SECTION 6.61)
Project Information
Project Name: Skyland Drive Townhomes
Project #: C190010
Designed by: BHE Date: 4/10/2019
Revised by: Date:
Revised by: Date:
Basin #
Basin Type =
Drainage Area (ac) =
Disturbed Area (ac) =
Runoff Coefficient (c) =
Rainfall Intensity "i" (in/hr) =
Flow (Q10) (cfs) =
Required surface area (so =
Reauired Storaae (cf) =
Schematic Storage Dimensions:
Basin Side Slopes ( x: 1 ) =
Storage Depth "Z" (ft) =
Bottom Dimension =
Top Dimension (sediment storage elevation) =
Top of Dam Dimension =
Storage Provided (cf) =
Surface Area Provided (so =
Designed Storage Dimensions:
1
Phase 1
Sediment
(Per NCDNER EC Manual Ch. 6, Sec. 6.61)
1.10
1.03
0.50
(Smooth bare packed soil)
0.30
(Undeveloped)
7.03
(5 min time of concentration - 10 Year Storm)
3.9
(Q=c*i*drainage area)
1,682
(435 sf per cfs of Q10 peak inflow)
1.980
(1800 cf per acre of disturbed area)
(may not be actual size or rectangular shape)
3.0
3.20
65.0ft x 32.0ft
84.2 ft x 51.2 ft
101.0 ft x 68.0 ft
10,225.7
4,311.0
Elev (ft)
Area (SF)
Volume (CF)
667
2,108
0
668
2,700
2,404
669
3,352
5,430
670
4,064
9,138
671
4,837
13,589
672
5,669
18,842
673
6,562
24,957
Designed Storage Elevation (ft)=
670.20
Designed Surface Area (so=
4,219 O.K. > Minimum Minimum Surface Area
Designed Storage Volume (co=
10,028 O.K. > Minimum Required Storage
Bottom Elevation (ft)=
667.0
Top of Dam Elevation (ft)=
673.0
Emergency Spillway Elevation (ft)=
670.2 Riser to be emergency overflow
Sizing of Skimmer Orifice Diameter:
Table 6.64a, EC Manual Ch. 6, Sec. 6.64
Skimmer
Head on
Size
Skimmer
Inches
Feet
Skimmer Size (in) =
2
1.5
0.125
Head on Skimmer (ft) =
0.167
2
0.167
Dewatered Volume (co =
1,980
2.5
0.208
Dewatering Time (days) =
3
3
0.25
Calculated Orifice Size (in) =
0.84
4
0.333
Actual Orifice Size (in) =
1.00
5
0.333
8
0.5

Sizing of Riser Overflow:
Qriser (cfs) =
Riser Diameter (in) _
Spillway Length (ft) =
Spillway Crest Elevation (ft) =
Design High Water Depth Over Spillway (in) =
Velocity Over Spillway (fps) =
Emergency Spillway Elevation (ft) =
Freeboard (ft) =
Filter Width (ft) =
Top of Berm Elevation (ft) =
3.9
16.0
670.2
2
1.3
670.2
2.6
n/a
673.0
(Q10)
(Use permanent control structure dimensions)
(4' x 4' pre -cast structure)
(spillway set from permanent pond design)
(Cw=3.0)
Riser to be emergency overflow
(1 ft minimum to top of basin)
(8 ft minimum)
(Top of Basin Elevation)
Sizing of Antiflotation Block:
Inside Length (ft) =
4
Inside width (ft) =
4
Wall Thickness (in) =
6
Top of Structure =
670.2
Bottom of Structure =
662.5
Bottom Slab Lip (in) =
6
Bottom Slab Thickness (in) =
6
Volume of Structure (cf) =
70
Weight of Structure (lb) =
10,436
Volume of Water Displaced (cf) =
193.3
Weight of Water Displaced (lb) =
12,059
Bottom Slab Size:
Bottom Slab Lip (in) =
8
Thickness (in) =
8.00
Weight of Anchor (lb) =
2,844
Factor of Safety =
1.1
Check Culvert Capacity:
Invert Elevation Down (ft):
662.00
Invert Elevation Up (ft):
662.47
Pipe Length (ft):
93.8
Slope (ft/ft):
0.0050
Pipe Diameter (in):
24
Mannings:
0.013
Q10 (cfs):
3.9
See attached Culvert Analysis
Velocity Q10 (fps):
1.7
O.K. Velocity < 10 fps

Culvert Report
Hydraflow Express Extension for Autodesk0 AutoCADO Civil 3D0 by Autodesk, Inc.
SB1 PH1
Invert Elev Dn (ft)
= 662.00
Calculations
Pipe Length (ft)
= 93.79
Qmin (cfs)
Slope (%)
= 0.50
Qmax (cfs)
Invert Elev Up (ft)
= 662.47
Tailwater Elev (ft)
Rise (in)
= 24.0
Shape
= Circular
Highlighted
Span (in)
= 24.0
Qtotal (cfs)
No. Barrels
= 1
Qpipe (cfs)
n-Value
= 0.013
Qovertop (cfs)
Culvert Type
= Circular Concrete
Veloc Dn (ft/s)
Culvert Entrance
= Square edge w/headwall (C)
Veloc Up (ft/s)
Coeff. K,M,c,Y,k
= 0.0098, 2, 0.0398, 0.67, 0.5
HGL Dn (ft)
HGL Up (ft)
Embankment
Hw Elev (ft)
Top Elevation (ft)
= 673.00
Hw/D (ft)
Top Width (ft)
= 12.00
Flow Regime
Crest Width (ft)
= 0.00
Ele (R)
674.00
672.00
670.00
66300
66a 00
664.00
662.00
660.00
SB1 PHI
10 20 30 40 50 60 70 50 90 100 110 120 130
Di-Iw C.I-t HGL Embank
Wednesday, Apr 10 2019
= 3.90
= 3.90
_ (dc+D)/2
= 3.90
= 3.90
= 0.00
= 1.73
= 4.04
= 663.35
= 663.16
= 663.43
= 0.48
= Inlet Control
ft Depth (R)
11.53
963
7M
5.53
353
1.53
-0.47
-2.47
140
Reach (ft)

SEDIMENT BASIN
(per NCDENR EROSION AND SEDIMENT CONTROL MANUAL SECTION 6.61)
Project Information
Project Name: Skyland Drive Townhomes
Project #: C190010
Designed by: BHE Date: 10/4/2019
Revised by: Date:
Revised by: Date:
Basin # 1 Phase 2
Basin Type = Sediment (Per NCDNER EC Manual Ch. 6, Sec. 6.61)
Drainage Area (ac) = 2.25
Disturbed Area (ac) = 2.25
Runoff Coefficient (c) = 0.50 (Smooth bare packed soil)
Rainfall Intensity "i" (in/hr) = 7.03 (5 min time of concentration - 10 Year Storm)
Flow (Q10) (cfs) = 7.9 (Q=c"i"drainage area)
Required surface area (sf) = 3,440 (435 sf per cfs of Q10 peak inflow)
Required Storage (cf) = 4.050 (1800 cf per acre of disturbed area)
Schematic Storage Dimensions: (may not be actual size or rectangular shape)
Basin Side Slopes ( x: 1 ) =
3.0
Storage Depth "Z" (ft) =
3.20
Bottom Dimension =
70.0 ft x 36.0 ft
Top Dimension (sediment storage elevation) =
89.2 ft x 55.2 ft
Top of Dam Dimension =
148.0 ft x 114.0 ft
Storage Provided (cf) =
11,910.1
Surace Area Provided (sf) =
4,923.8
Designed Storage Dimensions:
Elev (ft)
Area (SF)
Volume (CF)
666
2,383
0
667
2,878
668
3,398
5,781
669
3,949
9,455
670
4,532
13,695
671
5,327
18,625
672
1 6,208
1 24,392
673
7,126
31,059
Designed Storage Elevation (ft)=
670.20
Designed Surface Area (sf)=
4,691
O.K. > Minimum Minimum Surface Area
Designed Storage Volume (cf)=
14,681
O.K. > Minimum Required Storage
Bottom Elevation (ft)=
660.00
Top of Dam Elevation (ft)=
673.0
Emergency Spillway Elevation (ft)=
670.2
Riser to be emergency overflow
Sizing of Skimmer Orifice Diameter:
Table 6.64a, EC Manual Ch. 6, Sec. 6.64
Skimmer Head on
Size Skimmer
Inches Feet
Skimmer Size (in) =
2
1.5 0.125
Head on Skimmer (ft) =
0.167
2 0.167
Dewatered Volume (cf) =
4,050
2.5 0.208
Dewatering Time (days) =
3
3 0.25
Calculated Orifice Size (in) =
1.20
4 0.333
Actual Orifice Size (in) =
1.00
5 0.333

in #1 - Phase 2
Sizing of Riser Overflow:
Qriser (cfs) =
Riser Diameter (in) _
Spillway Length (ft) =
Spillway Crest Elevation (ft) =
Design High Water Depth Over Spillway (in) =
Velocity Over Spillway (fps) =
Emergency Spillway Elevation (ft) =
Freeboard (ft) =
Filter Width (ft) =
Top of Berm Elevation (ft) =
5.7
16.0
670.2
3
1.5
670.2
2.6
n/a
673.0
(Q10)
(Use permanent control structure dimensions)
(4' x 4' pre -cast structure)
(spillway set from permanent pond design)
(Cw=3.0)
Riser to be emergeny overflow
(1 ft minimum to top of basin)
(8 ft minimum)
(Top of Basin Elevation)
Sizing of Antiflotation Block:
Inside Length (ft) =
4
Inside width (ft) =
4
Wall Thickness (in) =
6
Top of Structure =
670.2
Bottom of Structure =
662.5
Bottom Slab Lip (in) =
8
Bottom Slab Thickness (in) =
8
Volume of Structure (cf) =
70
Weight of Structure (lb) =
10,436
Volume of Water Displaced (cf) =
193.3
Weight of Water Displaced (lb) =
12,059
Bottom Slab Size:
Bottom Slab Lip (in) =
8
Thickness (in) =
8.00
Weight of Anchor (lb) =
2,844
Factor of Safety =
1.1
Check Culvert Capacity:
Invert Elevation Down (ft):
662.00
Invert Elevation Up (ft):
662.47
Pipe Length (ft):
93.8
Slope (ft/ft):
0.0050
Pipe Diameter (in):
24
Mannings:
0.013
Q10 (cfs):
5.7
See attached Culvert Analysis
Velocity Q10 (fps):
2.4
O.K. Velocity < 10 fps

Culvert Report
Hydraflow Express Extension for Autodesk0 AutoCADO Civil 3D0 by Autodesk, Inc.
SB1 PH2
Invert Elev Dn (ft)
= 662.00
Calculations
Pipe Length (ft)
= 93.79
Qmin (cfs)
Slope (%)
= 0.50
Qmax (cfs)
Invert Elev Up (ft)
= 662.47
Tailwater Elev (ft)
Rise (in)
= 24.0
Shape
= Circular
Highlighted
Span (in)
= 24.0
Qtotal (cfs)
No. Barrels
= 1
Qpipe (cfs)
n-Value
= 0.013
Qovertop (cfs)
Culvert Type
= Circular Concrete
Veloc Dn (ft/s)
Culvert Entrance
= Square edge w/headwall (C)
Veloc Up (ft/s)
Coeff. K,M,c,Y,k
= 0.0098, 2, 0.0398, 0.67, 0.5
HGL Dn (ft)
HGL Up (ft)
Embankment
Hw Elev (ft)
Top Elevation (ft)
= 673.00
Hw/D (ft)
Top Width (ft)
= 12.00
Flow Regime
Crest Width (ft)
= 0.00
Ele (R)
674.00
672.00
670.00
66300
666 00
664.00
662.00
660.00
SB1 PH2
10 20 30 40 50 60 70 60 90 10❑ 110 120 130
Di-Iw C.I-t HGL Embank
Wednesday, Apr 10 2019
= 5.70
= 5.70
_ (dc+D)/2
= 5.70
= 5.70
= 0.00
= 2.39
= 4.53
= 663.42
= 663.31
= 663.66
= 0.59
= Inlet Control
ft Depth (R)
11.53
963
7M
5.53
353
1.53
-0.47
-2.47
140
Reach (ft)

SKIMMER SEDIMENT BASIN
(per NCDENR EROSION AND SEDIMENT CONTROL MANUAL SECTION 6.64)
Project Information
Project Name: Skyland Drive Townhomes
Project #: C190010
Designed by: BHE Date: 4/10/2019
Revised by: Date:
Revised by: Date:
Basin #
Basin Type =
Drainage Area (ac) =
Disturbed Area (ac) =
Runoff Coefficient (c) =
Rainfall Intensity "i" (in/hr) =
Flow (Q10) (cfs) =
Required surface area (sf) =
Reauired Storaae (cf) =
Schematic Storage Dimensions:
Basin Side Slopes ( x : 1 ) =
Storage Depth "Z" (ft) =
Bottom Dimension =
Top Dimension (sediment storage elevation) =
Top of Dam Dimension =
Storage Provided (cf) =
Surface Area Provided (sf) =
Designed Storage Dimensions:
2
Phase 1
Skimmer
(Per NCDNER EC Manual Ch. 6, Sec. 6.64)
1.17
1.05
0.50
(Smooth bare packed soil)
0.30
(Undeveloped)
7.03
(5 min Tc - 10 Year Storm, Rural Sub use 30 min.)
3.9
(Q=c*i*drainage area)
1,282
(325 sf per cfs of Q10 peak inflow)
2.106
(1800 cf per acre of disturbed area)
(may not be actual size or rectangular shape)
2.0
2.00
25.0 ft x 53.0 ft
33.0ft x 61.0ft
41.0ft x 69.0ft
3,338.0
2,013.0
Elev (ft)
Area (SF)
Volume (CF)
657
1,237
0
658
1,526
1,382
659
1,840
3,065
660
2,180
5,075
661
2,544
Designed Storage Elevation (ft)=
659.00
Designed Surface Area (sf)=
1,840
Designed Storage Volume (cf)=
3,065
Bottom Elevation (ft)=
657.0
Top of Dam Elevation (ft)=
661.0
Emergency Spillway Elevation (ft)=
659.5
O.K. > Minimum Minimum Surface Area
O.K. > Minimum Required Storage

Sizing of Skimmer Orifice Diameter:
Table 6.64a, EC Manual Ch. 6, Sec. 6.64
Skimmer
Head on
Size
Skimmer
Inches
Feet
Skimmer Size (in) =
2
1.5
0.125
Head on Skimmer (ft) =
0.167
2
0.167
Dewatered Volume (cf) =
2,106
2.5
0.208
Dewatering Time (days) =
3
3
0.25
Calculated Orifice Size (in) =
0.86
4
0.333
Actual Orifice Size (in) =
0.90
5
0.333
6
0.417
8
0.5
Sizing of Emergency Spillway:
Qspillway (cfs) =
3.9
(Q10)
Spillway Length (ft) =
20.0
(20 ft minimum spillway length, Cw=3.0)
Spillway Crest Elevation (ft) =
659.5
(1.0 ft min. above sediment storage depth)
Design High Water Depth Over Spillway (in) =
2
(6 in. maximum, Cw=3.0)
Velocity Over Spillway (fps) =
1.2
Freeboard (ft) =
1.3
(1 ft minimum)
Filter Width (ft) =
n/a
(8 ft minimum)
Top of Berm Elevation (ft) =
661.0
(Top of Basin Elevation)

SEDIMENT BASIN
DESIGN CRITERIA
DRAINAGE
AREA
>10 AC.
(ACRES)
<100 AC.
MIN.
LENGTH TO
2:1
WIDTH RATIO
MAX.
LENGTH TO
6:1
WIDTH RATIO
1800
MIN.
(CU. FT.
VOLUME
PER AC.
REQUIRED
DISTURBED)
435
SURFACE
(SQ.FT. PER
AREA
CFS Q10)
REQUIRED
DATA BLOCK
PLAN VIEW
INFLOW
STRUCTURE
AVERAGE AREA`
WIDTH W =
L
* AREA OF BASIN WATER SURFACE
AT TOP OF PRINCIPAL SPILLWAY
CROSS-SECTION VIEW SEE NOTE #3
T FREEBOARD
INFLOW 6" MIN. INVERT ELEVATION
STRUCTURE OF EMERGENCY SPILLWAY
PRIMARY SPILLWAY
2' 1MIN(RISER) w Il
DEWATERING
ZONE -
FILTER FABRIC
SEDIMENT
STORAGE ZONE
BAFFLE
L=20'
MIN.
3RD BAFFLE:
HARDWARE
CLOTH
SURROUNDING
SKIMMER
SER
NOTES:
1. REFER TO NCESCPDM
SECTION #6.61 FOR
ADDITIONAL DESIGN
SPECIFICATIONS
REGARDING SEDIMENT
BASINS.
2. REFER TO BAFFLE
INSTALLATION DETAIL FOR
BAFFLE SPACING AND
INSTALLATION.
3. FIRST BAFFLE IS TO BE
CONSTRUCTED OF
RIP -RAP AND #5 WASHED
STONE, WITH A MIN.
HEIGHT OF 3' AND MIN.
TOPWIDTH OF 2'.
4. FLASHBOARD RISER NOT
PERMITTED FOR USE
ANTI -SEEP
COLLAR NOT TO SCALE
PHASE
BASIN
DRAINAGE
AREA
(ACRES)
DENUDED
AREA
(ACRES)
Q10
(CFS)
BASIN VOLUME
SURFACE AREA
CLEANOUT
DEPTH H/2
(FT)
H
(FT)
Z
(FT)
L
(FT)
T
(FT)
W
(FT)
SKIMMER
PIPE
DIA.
SKIMMER
ORIFICE
DIA.
REQUIRED
(CF)
PROVIDED
(CF)
REQUIRED
(SF)
PROVIDED
(SF)
1
1
1.10
1.03
3.87
1,980
10,435
1,682
4,638
1.4
2.80
6
35
83.2
10
2
1.00
2
1 1
1 1.62
1 1.56
1 5.69
1 2,916
10,435
1 2,477
4,638
1 1.4
1 2.80
6
1 35
183.7
1 10
1 2
1 1.00
SEDIMENT BASIN
N.T.S.

SKIMMER SEDIMENT BASIN
DESIGN CRITERIA
DRAINAGE
AREA
< 10 AC.
(ACRES)
MIN.
LENGTH TO
2:1
WIDTH RATIO
MAX.
LENGTH TO
6:1
WIDTH RATIO
MIN.
1800
VOLUME
(CU. FT.
REQUIRED
PER AC.
DISTURBED)
325
SURFACE
(SQ. FT. PER
AREA
CFS Q10)
REQUIRED
DATA BLOCK
PLAN VIEW
IN
AVERAGE_
AREA* 1 1
WIDTH LENGTH \
* AREA OF BASIN WATER SURFACE
AT TOP OF PRIMARY SPILLWAY
CROSS-SECTION VIEW
INFLOW
DEWATERING
ZONE -
FILTER FABRIC
BAFFLES
10,
MIN.
SKIMMER
DEWATERING
DEVICE
v� BAFFLES
(CLDS
#30.19) 1' FREEBOARD
6" MAX. DEPTH OF FLOW OVER
EMERGENCY SPILLWAY
Z=5' MAX.
CLEANOUT SKIMMER AF
DEPTH LENGTH =
(H/2) 1' SEDIMENT H x 1.5
STORAGE (MIN. 5')
NOTES:
1.
REFER TO NCESCPDM
SECTION #6.64 FOR
ADDITIONAL DESIGN
EMBANKMENT
SPECIFICATIONS
REGARDING SKIMMER
SEDIMENT BASINS.
2.
REFER TO BAFFLE
INSTALLATION DETAIL FO
BAFFLE SPACING AND
INSTALLATION.
3.
TURBIDITY CURTAIN MAY
BE USED IN LIEU OF
POROUS BAFFLES.
4.
SKIMMER INVERT
ELEVATION = BASIN
EMERGENCY
BOTTOM + 1' MIN.
SPILLWAY
5.
H = SPILLWAY ELEVATION -
SKIMMER INVERT
L
ELEVATION
W=5' MIN.
EMBANKMENT
T=1.5' MIN.
H=Z MIN. EMERGENCY
SPILLWAY
SPECIFY
SEEPAGE
CONTROL NOT TO SCALE
MEASURES
PHASE
BASIN
DRAINAGE
AREA
(ACRES)
DENUDED
AREA
(ACRES)
Q10
(CFS)
BASIN VOLUME
SURFACE AREA
CLEANOUT
DEPTH Hl2
(FT)
H
(FT)
Z
(FT)
L
(FT)
T
(FT)
W
(FT)
SKIMMER
PIPE
DIA.
SKIMMER
ORIFICE
DIA.
REQUIRED
(CF)
PROVIDED
(CF)
REQUIRED
(SF)
PROVIDED
(SF)
1
2
1.17
1.05
3.94
2,106
3,065
1,282
1,840
1
2.00
4
20
1.5
5
2
0.90
SKIMMER SEDIMENT BASIN
N.T.S.

RIPRAP APRON
CALCULATIONS

20
10
R
3 0
l�l
Outlet IW = Do + La
pipe
i
diameter (Do)
La --•1
�,: T ilwater - 0.5Do
Al2-FES
18" Diameter
Q10=5.80cfs
La = 10'
d5O = 6"
W = 11.5'
3Do = 4.5'
t = 1.5'
1
toy`
r o,� p.P 60
L Qf i
Appendices
" I.,...I '.I....I 11'I.I IIII.I:'I.I....I I I I I 1 1 1 1 1 ' I I I I l I I'.I 'I I I I I.'i 10
3 5 10 20 50 100 200 500 1000
5.80 cfs Discharge (0/sec)
Curves may not be extrapolated.
Figure 8.06a Design of outlet protection protection from a round pipe flowing full, minimum tailwater condition (Tw < 0.5 diameter).
Rev. 12/93 8.06.3

3 0
l�l
Outlet IW = Do + La
pipe
i
diameter (Do)
La --•1
�,: T ilwater - 0.5Do
FES-C2
24" Diameter
Q10=1.33cfs
La =
13'
d5O
= 6"
W =
15'
3Do
= 6'
t = 1.5'
toy`
r o,� p.P 60
L Qf i
20
10
R
1
Appendices
"i_... I.,...I '.I....I I I I I I I '.I I I I''i10
3 5 10 20 50 100 200 500 1000
1.33 cfs Discharge (0/sec)
Curves may not be extrapolated.
Figure 8.06a Design of outlet protection protection from a round pipe flowing full, minimum tailwater condition (Tw < 0.5 diameter).
Rev. 12/93 8.06.3

APPENDICES

\ Raw
INV:666.2
R/W (PARTIALLY Bus
BURIED) D�D� SHEL TER
— — _ —R/W-- — R/W — — R/W — — R/W — — R/� R/W — — —R/W-- — R/W —
�___
R/W R/W — —
N v: 66 z 2 —�—
R /W —
— w —w
w--w n
\----\ w—
III �— --� ——w--w--w——w--w-- ——--w—I—w--w--w--w--w--w— W—
w w— w— w--w
v—,N--w--ate—— I'
—w--
�/W--W--w--w--
w — — w — — w ! — I I GE PA vEM�N
NV: 70.2 INV:670.6
ED
w W— IWj—W--Wof -- —w— W--VJ
675
R/W -� A13-FES — ICo
/ — EDGE OF PAVEMENT — D PP —
x �x�x � —lx x x x x z TE � 9y��
QV: 669.82
��/V�, B1 = — R/W — 8/ / R/W — ���� 18 o
A15-CB
68p 0.54 AC B1-FES 62-JB —� ` A13 R I -Cr
x
675 /W LP TANK
\ A14-CB 0.10 AC \ i R/W — — R/ l
\ /
8" HD lk\ \ 8" HDPE 8" E
/ R F DRA IN \ \ ROOF DRAIN I / I D AIN
S=2. % \ S=1.0% S= ° 0
ol
\ A15 \
AD 0.14 Ac �a
/ Al
RED 0.13c _ I
A5-CB A4-CB \ \ I I I
NOW OR FORMERLY I AS I / / / /A j
JOHNNIE F SULLIVAN x I
DB 7447, PG 58 I FO.24 Ac A7 °
PIN:5660-94-0591
TRACT 1 AND PART OF TRACT 2
MB 35, PG 33 AC
997. SKYLAND DR. A3 l / I \
MT. PLEASANT, NC 28124 x k / 6 A4 0.21 AC
0
ZONED "RL" / I� ° AS a ,
.06 AC
rw/A3-CB _ 0.07 Ac �` NOW OR FORMERLY
A8-CB/ A7-CB I I I \ qp JERRY R TUCKER &
O
/1 I cp ROSE P TUCKER
DB 12430, PG 49
°O PIN:5660-95-6392
i A9 A9-CB / // l �� A6 I A2 1 1
TRACT 1
/ / / / 0.13 AC / 3435 HIGHWAY 73 E
\ ��h 0.03 AC A6 CB A2-CB 0.06 Ac CONCORD, NC 28025
x R/W R R W I I I ZONED "RH"
DR
1 \ .00 OF
\ A10 / / / � \ \ / Al 5
x o.10 AC � /��1h / 1 1 1 III ,\
660 10.12 AC \
I I
x Al2-HW / \ \ \ \ \ \ \ \ /
x x
/ —
x c) C2-FES / \ \—
r/iceC1-CS
NOWOOR RGE FORMERLY HOE&
FREDA E. SHOE
PIN. 5660-95 7144
LOTS 35 40
1MB 08, OT
P LEA ANT, N 2
/ T.
MT. PLEASANT, NC 28124
ZONED "RH"
_ x- X
/X x x x _ _ _ R W / _ _ R� / R/ R/W — — R/W — — R/W
R/—� -- W —x — x /xW x— x x x— x xR/W x x x x/ x x I I CONCRETE
41 ORlVE
—w — w —
\ / R/W R/W
— —
R/W R/W —Ce>- — R/W — R/W — — R/V� s
GRAPHIC SCALE
30 0 15 30 60
( IN FEET )
1 inch = 30 ft.
LEGEND
PROPOSED CONCRETE AREAS
°
PROPOSED PAVEMENT
PROPOSED MILL & RESURFACE
RIP RAP
DI
DROP INLET
CB
CATCH BASIN
RCP
REINFORCED CONCRETE PIPE
FES
FLARED END SECTION
SSE
SANITARY SEWER EASEMENT
SIDE
STORM DRAIN EASEMENT
SWE
SIDEWALK EASEMENT
UE
UTILITY EASEMENT
BMP
BEST MANAGEMENT PRACTICE
EX. CATCH BASIN & PIPE
EX. STORM DRAIN & PIPE
R/W
RIGHT OF WAY LINE
PROPERTY LINE
ADJACENT PROPERTY LINE
EASEMENT LINE
—PCCE
— —PCCE
POST CONSTR. ACCESS EASEMENT
ss
ss
EX. G RAVITY S EW E R
UTUTUT
EX. UNDERGROUND TELEPHONE LINE
G
G
EX. GAS LINE
UGE
UGE
EX. UNDERGROUND ELECTRIC LINES
OE
OE
OE
EX. OVERHEAD ELECTRIC
www
EX. WATER LINE
STIPULATION FOR REUSE
THIS DRAWING WAS PREPARED FOR USE
ON A SPECIFIC SITE, SKYLAND DRIVE
TOWNHOMESI S. SKYLAND DRIVE, MT.
PLEASANT, INC, CONTEMPORANEOUSLY
WITH ITS ISSUE DATE ON 10/07/19. AND
IT IS NOT SUITABLE FOR USE ON A
DIFFERENT PROJECT SITE OR AT A LATER
TIME. USE OF THIS DRAWING FOR
REFERENCE OR EXAMPLE ON ANOTHER
PROJECT REQUIRES THE SERVICES OF
PROPERLY LICENSED ARCHITECTS AND
ENGINEERS. REPRODUCTION OF THIS
DRAWING FOR REUSE ON ANOTHER
PROJECT IS NOT AUTHORIZED AND MAY
BE CONTRARY TO THE LAW.
lJ 1
W
M'®
Cq
W
'--I
Co
®
W
Cn
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U
1/
W
0
a
Coo
MODIFICATION LOG
JOB NUMBER: C190010
CHECKED BY: BMF
DRAWN BY: BHE
DATE: 10-07-2019
1,88E-0 # W2il�
Z
t 10
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Q00
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.` V o
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SHEET:
C49 1

\ Raw
_R/W_- - R - - R/W - - R/W - - R/W NN - R/W - R/W - -
- -R/W-- _ R/W /
OE-OE-OEOEOE OE -O - _
- OE �E -OE� OE OE -eE DOE OE OE OE OE � R/W _
- - `' ('-OE-OE-OE--OEM- _ R W
_ \
_- - IVE S•R• OE-OE--OE--OE--OE--OE-- OE - -OE - - OE - U--
W_- W ��
I \ _ - w - - w - w - - (60 PUBLIC R/W -MAINTAINED) ou- -
\ � W--w- yq� w--w=-7nt- -- �
w--w--w----w--w--v�wv� -w w--;�w--w--w--w--w--w--w--w-- - �-w--w--w- �
w--w--w--w;�w
_R/W �\-o�-°€- -� - --of-�oL-�s- -�-�s-�s- I
OEOE - OE - /\�__----�- dS
BENCHMARK �- -OE - OE---- OF= - OE -�OE I E n E - OE _ OE OE- °E - - OE -
NAIL IN PP _ \ \ \ _
ELV. 6B0.32 K/W� \ K/W� R/W 9� /\_ J J ,, _ - 0� = II�-ODE - E - --OE --
(NAVDBB) soft\ V A / \ �\ LL �_ _ - °€- o_E -��
TEMPORARY R/W
CONSTRUCTION R/W -
\ ENTRANCE
ROCK PIPE INLET
PROTECTION \ �
v � 40a CONCR TE SILT FEK"TYP )
LIMITS OF WAS LIT LL
SILT FENCE (TYP.) DISTURBANCE (TYP.) ' �\� ` I � ` )
S RAINAGE AREA a LIMITS OF v
B P.)
B IN Nl)�A\BER 1
PHA E\
\
BASIN TYPE: SKIMMER \
\ v / DRAINAGE AREA: 1.17 AC-
\ DISTURBED AREA: 1.05 AC lwoo
x \ \ 9�` \ ' / / / \ \ ago ova
REQD. SURFA�E ARE :T 1,28 FS-
\ PROV. SURFACE AREA 1840 SSF
I -
x /„ J / E n B �TORAG OL: 2,106 CF
NOW OR FORMERLY I \ I / / / PROM STORAGE VOL: 3,065 CF \
BOTTOM ELEV: 657.00
JOHNNIE F SULLIVAN x a / / STORAGE ELEV: 659.00 _
DB 7447, PG 58 ( SOIL STOCK ILE AREA I i / / CLEAN OUT DEPTH 1.00,
EV': \
PIN: 5660-94-0591 I / \ I / / / TOP OF BERM EL61. 0
TRACT 1 AND PART OF TRACT 2 EMER. SPILLWAY ELEV:6 5 \ `
MB 35, PG 33 \ / % / / / / EMER. SPILLWAY WIDTH: 20' \ I
997. SKYLAND DR. l ) I / / / \ SKIMMER PIPE DIlk- 9 0\
MT. PLEASANT, NC 28124 x ROCK CHECK DAM (TYP.) / / SKIMMER ORIFICE DIA: \
ZONED "RL" -2-SKIM-MB ER SKIM- WIT-W INV UP: 6 7.
0.9"ORIFICE \ INV DOWN: 6 .0� SB2 1 D AIN E AREA (
BASIN NUMBER: 1 x I / / / / I I \ \ I NOW OR FORMERLY
PHASE: 1 / ) / TEMPORARY DIVERSION S JERRY R TUCKER &
DITCH (TYP.) / ROSE P TUCKER
BASIN TYPE: SEDIMENT x / / 66� �MIN.10' I I I I I I \ \ \ \ I DB 12430, PG 49
DRAINAGE AREA: 1.10 AC
/ / � \ PIN: 5660-95-6392
DISTURBED AREA: 1.03 AC SILT FENCE (TYP.) RIP AP A PRO I I I \ 1 I TRACT 1
Q10: 3.9 CFS x
MB 72, PG 107
REQD. SURFACE AREA: 1,682 SF T / / h 3435 HIGHWAY 73 E
PROV. SURFACE AREA: 4,219 SF
I I / CONCORD, NC 28025
READ. STORAGE VOL: 1,9
80 CF �� / / / /\ TEMPORARY I I / I I I I i I ZONED "RH"
PROV. STORAGE VOL: 10,028 CF �� / / / / / SLOPE DRAINELEV: 667.00
1 I I
STOORAGE TTOM ELEV: 670.20 /\ / / / / AzR K PIPE INLET
P TECIO I \ I \ I I )
CLEAN OUT DEPTH: 1.60'
-
TOP OF BERM ELEV: 673.00 �� / / c / 660
SKIMMER PIPE DIA: - 2.0" / TEMP RWRY DIV ON I I X
SKIMMER ORIFICE DIA: 1.0" \\ - �� 1 ROCK PIPE INLET TEMP ARY / / / 660 0 I C I
RISER TOP ELEV: 670.20 �� / / / / / o o
PE DRAIN
RISER DIA: 4' X 4' PRECAST STRUCTURE \/ 685 PROTECTION / �
CULVERT DIA: 24" RCP �I ITSF �/ ISTURB C P RAP RON � I L1DIS URBED
CULVER LENGTH: 94' / / 655 0' E ER EN Y SPILLW V CK CH DA TV
INV UP: 657.00 x / /gyp- / / /s( I
INV DOWN: 654.00
RIPRAP APRON
x
BAFFLES
MIN. 10'SPACING x
/ / / '-
/ �X \X /
� X
24 RCPF (S�,�
// \
EXISTING POND
i 4' X 4' PRECAST
STRUCTURE
/ SEE SHEET C5.1
FOR DETAILS
SKIMMER WITH 1�.
.0" ORIFICE \.
i
F
x= - '� =x - x R/xW x- x x x- x xR/W x x
EROSION AND SEDIMENT CONTROL NOTES:
1. IF NECESSARY, SLOPES WHICH EXCEED EIGHT (8) FEET SHOULD BE STABILIZED WITH SYNTHETIC OR VEGETATIVE MAT,
IN ADDITION TO HYDROSEEDING. IT MAY BE NECESSARY TO INSTALL TEMPORARY SLOPE DRAINS DURING
CONSTRUCTION. TEMPORARY BERMS MAY BE NEEDED DAILY UNTIL THE SLOPE IS BROUGHT TO GRADE.
2. STABILIZATION MEASURES SHALL BE INITIATED AS SOON AS PRACTICABLE IN PORTIONS OF THE SITE WHERE
CONSTRUCTION ACTIVITIES HAVE TEMPORARILY OR PERMANENTLY CEASED, BUT IN NO CASE MORE THAN FOURTEEN
(14) DAYS AFTER WORK HAS CEASED, EXCEPT AS STATED BELOW:
ALL PERIMETER DIKES, SWALES, DITCHES, PERIMETER SLOPES AND ALL SLOPES STEEPER THAN 3 HORIZONTAL TO 1
VERTICAL (3:1) SHALL BE PROVIDED TEMPORARY OR PERMANENT STABILIZATION WITH GROUND COVER AS SOON
AS PRACTICABLE BUT IN ANY EVENT WITHIN 7 CALENDAR DAYS FROM THE LAST LAND -DISTURBING ACTIVITY. ALL
OTHER DISTURBED AREAS SHALL BE PROVIDED TEMPORARY OR PERMANENT STABILIZATION WITH GROUND
COVER AS SOON AS PRACTICABLE BUT IN ANY EVENT WITHIN 14 CALENDAR DAYS FROM THE LAST
LAND -DISTURBING ACTIVITY.
3. ALL CUT AND FILL SLOPES AND CHANNEL SIDE SLOPES WHICH ARE NOT TO BE PAVED SHALL BE SEEDED UNTIL A GOOD
STAND OF GRASS IS OBTAINED IN ACCORDANCE WITH THE SEEDING SCHEDULE ON SHEET C7.4. ALL SEEDING WILL BE
MULCHED.
4. ALL SEDIMENT AND EROSION CONTROL DEVICES SHALL BE INSPECTED EVERY SEVEN (7) DAYS AND WITHIN 24 HOURS
AFTER EACH RAINFALL OCCURRENCE THAT EXCEEDS ONE-HALF (0.5) INCH. IF SITE INSPECTIONS IDENTIFY BMPS THAT
ARE DAMAGED OR NOT OPERATING EFFECTIVELY, MAINTENANCE MUST BE PERFORMED AS SOON AS PRACTICABLE OR
AS REASONABLY POSSIBLE AND BEFORE THE NEXT STORM EVENT WHENEVER PRACTICABLE.
5. IF WATER IS ENCOUNTERED WHILE TRENCHING, THE WATER SHOULD BE FILTERED TO REMOVE ANY SEDIMENTS
BEFORE BEING PUMPED BACK INTO ANY STORMWATER SYSTEMS, WATER COURSES AND WATERS OF THE STATE (WOS)
OR WATERS OF THE UNITED STATES (WOU.S.).
6. ALL EROSION CONTROL DEVICES SHALL BE PROPERLY MAINTAINED DURING ALL PHASES OF CONSTRUCTION UNTIL THE
COMPLETION OF ALL CONSTRUCTION ACTIVITIES AND ALL DISTURBED AREAS HAVE BEEN STABILIZED. ADDITIONAL
CONTROL DEVICES MAY BE REQUIRED DURING CONSTRUCTION IN ORDER TO CONTROL EROSION AND/OR OFFSITE
SEDIMENTATION. ALL TEMPORARY CONTROL DEVICES SHALL BE REMOVED ONCE CONSTRUCTION IS COMPLETE AND
THE SITE IS STABILIZED.
7. THE CONTRACTOR MUST TAKE NECESSARY ACTION TO MINIMIZE THE TRACKING OF MUD ONTO PAVED ROADWAY
FROM CONSTRUCTION AREAS AND THE GENERATION OF DUST. THE CONTRACTOR SHALL DAILY REMOVE MUD/SOIL
FROM PAVEMENT, AS MAY BE REQUIRED.
8. ALL CONSTRUCTION TRAFFIC SHALL ENTER AND EXIT THE SITE VIA THE CONSTRUCTION ENTRANCE.
9. EXCAVATED MATERIAL FROM TRENCHES SHALL BE PLACED ON THE UPGRADE SIDE OF THE TRENCH TO ALLOW
MATERIAL TO ERODE INTO THE TRENCH. CONSTRUCTION MAINTENANCE AND REMOVAL OF ALL EROSION CONTROL
DEVICES ARE THE RESPONSIBILITY OF GRADING CONTRACTOR UNLESS OTHERWISE NOTED.
10. THE EROSION CONTROL MEASURES SHOWN ON THIS DRAWING ARE RECOMMENDED AT A MINIMUM. ACTUAL
MEASURE NECESSARY FOR CONTAINMENT OF RUN-OFF SHALL BE THE RESPONSIBILITY OF THE CONTRACTOR AND B
FIELD VERIFIED.
11. ADDITIONAL MEASURES TO CONTROL EROSION AND SEDIMENT MAY BE REQUIRED BY A REPRESENTATIVE OF THE
TOWN ENGINEERING DEPARTMENT.
12. SLOPES SHALL BE GRADED NO STEEPER THAN 2:1. FILL SLOPES GREATER THAN 10' REQUIRE ADEQUATE TERRACING
13. A GRADING PLAN MUST BE SUBMITTED FOR ANY LOT GRADING EXCEEDING ONE ACRE THAT WAS NOT PREVIOUSLY
APPROVED.
14. ON -SITE BURIAL PITS ARE NOT ALLOWED, UNLESS WRITTEN APPROVAL IS RECEIVED FROM THE OWNER AND AN
ON -SITE DEMOLITION LANDFILL PERMIT IS RECEIVED FROM THE ZONING ADMINISTRATOR.
15. GRADING MORE THAN ONE ACRE WITHOUT AN APPROVED EROSION CONTROL PLAN IS A VIOLATION OF THE
TOWN/COUNTY EROSION CONTROL ORDINANCE AND IS SUBJECT TO A FINE.
16. DRIVEWAY PERMIT FOR CONSTRUCTION ENTRANCES IN NCDOT RIGHT OF WAY MUST BE PRESENTED AT
PRE -CONSTRUCTION MEETING.
17. A PREWORK MEETING SHALL BE SCHEDULED WITH THE TOWN INSPECTOR PRIOR TO CONSTRUCTION.
18. APPROVAL OF THE EROSION AND SEDIMENT CONTROL PLANS BY THE TOWN OF MT. PLEASANT GRANTS COVERAGE
THE DEVELOPMENT UNDER THE STATE OF NORTH CAROLINA DEPARTMENT OF ENVIRONMENTAL QUALITY RESOUR
(NCDEQ) DIVISION OF WATER QUALITY (DWQ) GENERAL PERMIT - NCG 010000 TO DISCHARGE STORMWATER UND
THE NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM FOR CONSTRUCTION ACTIVITIES. THE FINANCIALLY
RESPONSIBLE PARTY FOR THIS DEVELOPMENT IS RESPONSIBLE FOR MEETING THE REQUIREMENTS OF THE GENERA
PERMIT.
19. LITTER, CONSTRUCTION DEBRIS, OILS, FUELS AND BUILDING PRODUCTS WITH SIGNIFICANT POTENTIAL FOR IMPACT
(SUCH AS STOCKPILES OF FRESHLY TREATED LUMBER) AND CONSTRUCTION CHEMICALS THAT COULD BE EXPOSED
STORM WATER MUST BE PREVENTED FROM BECOMING A POLLUTANT SOURCE IN STORM WATER DISCHARGES.
20. SHOW BMP MEASURES FOR CONCRETE TRUCK WASHOUT AREA, OR ADD THE FOLLOWING NOTES:
CONCRETE TRUCKS SHALL NOT TYPICALLY BE WASHED OUT ON SITE. IF CONCRETE TRUCK WASHOUT IS PERM(
ON SITE, COORDINATE LOCATION AND BMP'S WITH SITE INSPECTOR.
DO NOT DISPOSE OF CONCRETE TRUCK WASHOUT WASTE BY DUMPING INTO A SANITARY SEWER, STORM DRA
OR ONTO SOIL OR PAVEMENT THAT CARRIES STORM WATER RUNOFF.
PERMIT
ELEV. �59
x
�\ \I (SILT FENCE (TYP.)
x
F x
TR P OT\T ON \\ \� \ /I
\ \\ \ \-x x x x \x \\
0 V /
I� I I
NOW OR FORMERLY
GEORGE A SHOE &
I FREDA E. SHOE
DB 545, PG. 330
PIN:5660-95-7144
I \ 1 I I LOTS 35-40
MB 8, PG 63
1010 ABBOTT ST.
MT. PLEASANT, NC 28124
ZONED "RH"
i II l/1 I�I
I I I I I I I I
R/W - _ R� / R/W - - R/\n/ - p�\n/
/ / + + bE"--� OE - OE 'OE " -OE
-
7 E- OE -pE-
X X X X -x / 0- OE--OET- OE- -OE-
ABBOTT STREET / M 7`1x
(40' PUBLIC R/W)
(PB 8/63, DB 350/510) �w - �, Z_
CONCRETE TRUCK WASHOUT SHALL BE DISPOSED OF IN ACCORDANCE WITH THE FOLLOWING: /
DESIGNATED AREA THAT WILL LATER BE BACKFILLED (SLURRY PIT) I \ l RIM 690, 77
DESIGNATED AREA WHERE CONCRETE WASH CAN HARDEN AND BE DISPOSED OF AS SOLID WASTE. INV: 685.12
LOCATION THAT IS NOT SUBJECT TO WATER RUNOFF, AND MORE THAN 50 FEET AWAY FROM A STORM DRAIN, / o ( / (HEAD OF LINE)
OPEN DITCH, OR RECEIVING WATER WAY.
PUMP EXCESS CONCRETE IN CONCRETE PUMP BIN BACK INTO CONCRETE MIXER TRUCK. o I
CONCRETE WASHOUT FROM CONCRETE PUMPER BINS CAN BE WASHED INTO CONCRETE PUMPER TRUCKS AND - oe
DISCHARGED INTO DESIGNATED WASHOUT AREA OR PROPERLY DISPOSED OF OFFSITE. -�I°E- - oe _ A
Ljj
21. ALL CHEMICAL SPILLS, OIL SPILLS, OR FISH KILLS MUST BE REPORTED TO NCDEQ- CALL THE 24-HOUR EMERGENCY N M
RESPONSE LINE AT 1-800-858-0368.Lij
m
22. TEMPORARY TOILET FACILITIES SHALL BE PROVIDED FOR ALL CONSTRUCTION WORKERS AND SITE VISITORS IN I \ a a
ACCORDANCE WITH 2O06 INTERNATIONAL PLUMBING CODE GENERAL REGULATIONS, SECTION 311. PORTABLE N 0, Q, c
FACILITIES SHALL BE PLACED ON LEVEL GROUND AND AWAY FROM STORM DRAINAGE SYSTEMS (DITCHES, CATCH N W
BASINS, ETC.). DISPOSAL AND HANDLING OF SANITARY WASTE MUST COMPLY WITH STATE AND LOCAL
REQUIREMENTS.
23. FINAL GRADES FOR GRASSED AND LANDSCAPED AREAS SHALL REQUIRE A MINIMUM OF 4-6" OF CLEAN TOP SOIL, FREE SSMH
OF DEBRIS AND CONTAMINANTS, AND PREFERABLY OF NATIVE ORIGIN. S RIM: 688.83
INV: 683.73
24. SILT FENCE AND TREE PROTECTION SHOWN OFFSET FROM LIMITS OF DISTURBANCE FOR CLARIFICATION PURPOSES.
TO
CES 25. CONCRETE WASHOUT STATION AND STOCKPILES SHOULD NOT BE LOCATED WITHIN 50 FEET OF ANY STORM DRAINS,
ER BASINS, OR STREAMS UNLESS NO ALTERNATIVE IS FEASIBLE.
L 26. ANY OFF -SITE BORROW AND WASTE REQUIRED FOR THIS PROJECT MUST COME FROM A SITE WITH AN APPROVED
EROSION CONTROL PLAN, A SITE REGULATED UNDER THE MINING ACT OF 1971, OR A LANDFILL REGULATED BY THE
DIVISION OF SOLID WASTE MANAGEMENT. TRASH/DEBRIS FROM DEMOLITION ACTIVITIES OR GENERATED BY ANY
ACTIVITIES ON SITE MUST BE DISPOSED OF AT A FACILITY REGULATED BY THE DIVISION OF SOLID WASTE
TO MANAGEMENT OR PER DIVISION OF SOLID WASTE MANAGEMENT OR DIVISION OF WATER RESOURCES RULES AND
REGULATIONS.
27. PER SECTION 6.20 OF THE NORTH CAROLINA EROSION AND SEDIMENT CONTROL PLANNING AND DESIGN MANUAL,
DIVERSIONS THAT WILL STAY IN PLACE LONGER THAN 30 WORKING DAYS SHOULD BE SEEDED AND MULCHED AS SOON
AS THEY ARE CONSTRUCTED TO PRESERVE DIKE HEIGHT AND REDUCE MAINTENANCE.
GRAPHIC SCALE
30 0 15 30 60
( IN FEET)
1 inch = 30 ft.
LEGEND
WETLANDS
_SF
SILT FENCE
-sF SF -
SILT FENCE OUTLET
TP
TREE PROTECTION FENCE
■
TRIBUTARY AREA
HE
LIMITS OF DISTURBANCE
ARK
ROCK CHECK DAM
rl
INLET PROTECTION
GENERAL NOTES
1. ALL MATERIALS, CONSTRUCTION, AND PLANS ARE TO COMPLY WITH CURRENT
TOWN OF MT. PLEASANT AND NCDENR STANDARD SPECIFICATIONS AND
DETAILS.
2. CONTACT NORTH CAROLINA ONE CALL SERVICE @ 811 OR 800-632-4949 AND
TOWN OF MT. PLEASANT, A MINIMUM OF 72 HOURS BEFORE DIGGING.
3. ANY SITE GRADING SHALL COMPLY WITH INTENT OF ORIGINAL DEVELOPMENT
GRADING AND DRAINAGE PLANS.
4. THE CONTRACTOR SHALL VERIFY ALL EXISTING STRUCTURES PRIOR TO
CONSTRUCTION. ALL DISCREPANCIES SHALL BE REPORTED TO THE ENGINEER.
5. NO BMPS SHALL BE PLACED ON ADJACENT PROPERTY WITHOUT THE WRITTEN
CONSENT OF THE PROPERTY OWNER AND THE TOWN OF MT. PLEASANT.
6. THE NCDENR EROSION CONTROL MANUAL AND TOWN OF MT. PLEASANT
STANDARDS SHALL BE USED AS A GUIDELINE FOR IMPPLEMENTATION AND
MAINTENANCE OF BMPS. THE FOLLOWING BMPS:
• SURFACE ROUGHENING
• STABILIZED CONSTRUCTION ENTRANCE
• SILT FENCE
• HARDWARE FABRIC AND STONE INLET PROTECTION
• CHECK DAMS
• TEMPORARY SEEDING
• PERMANENT SEEDING
• MULCHING
• SOD
SITE INFO
CONSTRUCTION START DATE: AUGUST, 2019
DISTURBED AREA: 3.09 ACRES
CONSTRUCTION SEQUENCE
1. OBTAIN ALL REQUIRED PERMITS.
2. SET UP AN ON -SITE PRE CONSTRUCTION CONFERENCE WITH THE EROSION
CONTROL INSPECTOR TO DISCUSS EROSION CONTROL MEASURES. FAILURE
TO SCHEDULE SUCH CONFERENCE 48 HOURS PRIOR TO ANY LAND
DISTURBING ACTIVITY IS A VIOLATION OF THE TOWN CODE AND IS SUBJECT
TO FINE.
3. MAKE ANY REQUIRED MODIFICATIONS TO THE EROSION AND SEDIMENT
CONTROL PLANS. ALL MODIFICATIONS TO THE EROSION AND SEDIMENT
CONTROL PLANS SHALL BE DOCUMENTED ON THE ON -SITE APPROVED PLANS.
4. INSTALL GRAVEL CONSTRUCTION ENTRANCE ON S. SKYLAND DRIVE.
5. INSTALL PERIMETER SILT FENCE, INLET PROTECTION, SEDIMENT BASINS,
TEMPORARY DIVERSION DITCHES AND OTHER MEASURES AS SHOWN ON THE
PLANS CLEARING ONLY AS NECESSARY TO INSTALL THESE DEVICES.
6. CALL FOR ON -SITE INSPECTION BY THE EROSION CONTROL INSPECTOR. WHEN
APPROVED, THE INSPECTOR ISSUES THE GRADING PERMIT AND CLEARING
AND GRUBBING MAY BEGIN.
7. LIMIT CLEARING AND GRUBBING OF THE SITE TO AREAS THAT WILL BE MASS
GRADED. WHENEVER POSSIBLE, EXISTING VEGETATION SHALL REMAIN IN
PLACE TO PREVENT EROSION OF THE SITE.
8. BEGIN MASS GRADING ACTIVITIES. AS SITE IS GRADED AND PADS BUILT UP,
CONTRACTOR SHALL MINIMIZE THE AMOUNT OF STORMWATER FLOWING
OVER FILL SLOPES BY USING DIVERSION DITCHES AND SLOPE DRAINS. DITCHES
AND SLOPE DRAINS SHOWN ON PLANS DEPICT THE REQUIRED DIVERSION
DITCHES AND SLOPE DRAINS AT FINAL PAD GRADE. ADDITIONAL MEASURES
MAY BE NEEDED AS PROGRESSES. CONTRACTOR SHALL LIMIT DRAINAGE
AREAS FLOWING TO EACH OF THE PROPOSED BASINS TO THE MAXIMUM
AREA THAT IS DESIGNATED FOR EACH BASIN. THIS SHALL BE ACCOMPLISHED
BY ADJUSTING THE PROPOSED DIVERSION DITCHES AS THE SITE IS GRADED.
SOIL MAP LEGEND
E n D Enon Sandy Loam
E n B Enon Sandy Loam
STIPULATION FOR REUSE
THIS DRAWING WAS PREPARED FOR USE
ON A SPECIFIC SITE, SKYLAND DRIVE
TOWNHOMES, S. SKYLAND DRIVE, MT.
PLEASANT, INC, CONTEMPORANEOUSLY
WITH ITS ISSUE DATE ON 10/07/19. AND
IT IS NOT SUITABLE FOR USE ON A
DIFFERENT PROJECT SITE OR AT A LATER
TIME. USE OF THIS DRAWING FOR
REFERENCE OR EXAMPLE ON ANOTHER
PROJECT REQUIRES THE SERVICES OF
PROPERLY LICENSED ARCHITECTS AND
ENGINEERS. REPRODUCTION OF THIS
DRAWING FOR REUSE ON ANOTHER
PROJECT IS NOT AUTHORIZED AND MAY
BE CONTRARY TO THE LAW.
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DATE: 10-07-2019
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STORAGE ELEV: 670.20
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SKIMMER PIPE DIA: 2.0"
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EROSION AND SEDIMENT CONTROL NOTES: /.
1. IF NECESSARY, SLOPES WHICH EXCEED EIGHT (8) FEET SHOULD BE STABILIZED WITH SYNTHETIC OR VEGETATIVE MAT, 10. THE EROSION CONTROL MEASURES SHOWN ON THIS DRAWING ARE RECOMMENDED AT A MINIMUM. ACTUAL CONCRETE TRUCK WASHOUT SHALL BE DISPOSED OF IN ACCORDANCE WITH THE FOLLOWING: /
IN ADDITION TO HYDROSEEDING. IT MAY BE NECESSARY TO INSTALL TEMPORARY SLOPE DRAINS DURING MEASURE NECESSARY FOR CONTAINMENT OF RUN-OFF SHALL BE THE RESPONSIBILITY OF THE CONTRACTOR AND BE /
CONSTRUCTION. TEMPORARY BERMS MAY BE NEEDED DAILY UNTIL THE SLOPE IS BROUGHT TO GRADE. FIELD VERIFIED. DESIGNATED AREA THAT WILL LATER BE BACKFILLED (SLURRY PIT) /� I RIM 690,77
DESIGNATED AREA WHERE CONCRETE WASH CAN HARDEN AND BE DISPOSED OF AS SOLID WASTE. I I �INV: 685,12
2. STABILIZATION MEASURES SHALL BE INITIATED AS SOON AS PRACTICABLE IN PORTIONS OF THE SITE WHERE 11. ADDITIONAL MEASURES TO CONTROL EROSION AND SEDIMENT MAY BE REQUIRED BY A REPRESENTATIVE OF THE LOCATION THAT IS NOT SUBJECT TO WATER RUNOFF, AND MORE THAN 50 FEET AWAY FROM A STORM DRAIN, / o i (HEAD DE LINE)
CONSTRUCTION ACTIVITIES HAVE TEMPORARILY OR PERMANENTLY CEASED, BUT IN NO CASE MORE THAN FOURTEEN TOWN ENGINEERING DEPARTMENT. OPEN DITCH, OR RECEIVING WATER WAY.
(14) DAYS AFTER WORK HAS CEASED, EXCEPT AS STATED BELOW: PUMP EXCESS CONCRETE IN CONCRETE PUMP BIN BACK INTO CONCRETE MIXER TRUCK. o I
12. SLOPES SHALL BE GRADED NO STEEPER THAN 2:1. FILL SLOPES GREATER THAN 10' REQUIRE ADEQUATE TERRACING. - CONCRETE WASHOUT FROM CONCRETE PUMPER BINS CAN BE WASHED INTO CONCRETE PUMPER TRUCKS AND P`D - oe OE
ALL PERIMETER DIKES, SWALES, DITCHES, PERIMETER SLOPES AND ALL SLOPES STEEPER THAN 3 HORIZONTAL TO 1 DISCHARGED INTO DESIGNATED WASHOUT AREA OR PROPERLY DISPOSED OF OFFSITE. of
VERTICAL (3:1) SHALL BE PROVIDED TEMPORARY OR PERMANENT STABILIZATION WITH GROUND COVER AS SOON 13. A GRADING PLAN MUST BE SUBMITTED FOR ANY LOT GRADING EXCEEDING ONE ACRE THAT WAS NOT PREVIOUSLY I LN.,1
AS PRACTICABLE BUT IN ANY EVENT WITHIN 7 CALENDAR DAYS FROM THE LAST LAND -DISTURBING ACTIVITY. ALL APPROVED. 21. ALL CHEMICAL SPILLS, OIL SPILLS, OR FISH KILLS MUST BE REPORTED TO NCDEQ- CALL THE 24-HOUR EMERGENCY
OTHER DISTURBED AREAS SHALL BE PROVIDED TEMPORARY OR PERMANENT STABILIZATION WITH GROUND RESPONSE LINE AT 1-800-858-0368.
COVER AS SOON AS PRACTICABLE BUT IN ANY EVENT WITHIN 14 CALENDAR DAYS FROM THE LAST 14. ON -SITE BURIAL PITS ARE NOT ALLOWED, UNLESS WRITTEN APPROVAL IS RECEIVED FROM THE OWNER AND AN _� LLI M oo
LAND DISTURBING ACTIVITY. ON -SITE DEMOLITION LANDFILL PERMIT IS RECEIVED FROM THE ZONING ADMINISTRATOR. 22. TEMPORARY TOILET FACILITIES SHALL BE PROVIDED FOR ALL CONSTRUCTION WORKERS AND SITE VISITORS IN ° a a
ACCORDANCE WITH 2O06 INTERNATIONAL PLUMBING CODE GENERAL REGULATIONS, SECTION 311. PORTABLE 10, Q, o
3. ALL CUT AND FILL SLOPES AND CHANNEL SIDE SLOPES WHICH ARE NOT TO BE PAVED SHALL BE SEEDED UNTIL A GOOD 15. GRADING MORE THAN ONE ACRE WITHOUT AN APPROVED EROSION CONTROL PLAN IS A VIOLATION OF THE FACILITIES SHALL BE PLACED ON LEVEL GROUND AND AWAY FROM STORM DRAINAGE SYSTEMS (DITCHES, CATCH W
STAND OF GRASS IS OBTAINED IN ACCORDANCE WITH THE SEEDING SCHEDULE ON SHEET C7.4. ALL SEEDING WILL BE TOWN/COUNTY EROSION CONTROL ORDINANCE AND IS SUBJECT TO A FINE. BASINS, ETC.). DISPOSAL AND HANDLING OF SANITARY WASTE MUST COMPLY WITH STATE AND LOCAL
MULCHED. REQUIREMENTS.
16. DRIVEWAY PERMIT FOR CONSTRUCTION ENTRANCES IN NCDOT RIGHT OF WAY MUST BE PRESENTED AT
4. ALL SEDIMENT AND EROSION CONTROL DEVICES SHALL BE INSPECTED EVERY SEVEN (7) DAYS AND WITHIN 24 HOURS PRE -CONSTRUCTION MEETING. 23. FINAL GRADES FOR GRASSED AND LANDSCAPED AREAS SHALL REQUIRE A MINIMUM OF 4-6" OF CLEAN TOP SOIL, FREE SSMH
AFTER EACH RAINFALL OCCURRENCE THAT EXCEEDS ONE-HALF (0.5) INCH. IF SITE INSPECTIONS IDENTIFY BMPS THAT OF DEBRIS AND CONTAMINANTS, AND PREFERABLY OF NATIVE ORIGIN. S RIM: 688,5,1,
ARE DAMAGED OR NOT OPERATING EFFECTIVELY, MAINTENANCE MUST BE PERFORMED AS SOON AS PRACTICABLE OR
17. A FIREWORK MEETING SHALL BE SCHEDULED WITH THE TOWN INSPECTOR PRIOR TO CONSTRUCTION. �INV: 68I3
AS REASONABLY POSSIBLE AND BEFORE THE NEXT STORM EVENT WHENEVER PRACTICABLE. 24. SILT FENCE AND TREE PROTECTION SHOWN OFFSET FROM LIMITS OF DISTURBANCE FOR CLARIFICATION PURPOSES.
18. APPROVAL OF THE EROSION AND SEDIMENT CONTROL PLANS BY THE TOWN OF MT. PLEASANT GRANTS COVERAGE TO
5. IF WATER IS ENCOUNTERED WHILE TRENCHING, THE WATER SHOULD BE FILTERED TO REMOVE ANY SEDIMENTS THE DEVELOPMENT UNDER THE STATE OF NORTH CAROLINA DEPARTMENT OF ENVIRONMENTAL QUALITY RESOURCES 25. CONCRETE WASHOUT STATION AND STOCKPILES SHOULD NOT BE LOCATED WITHIN 50 FEET OF ANY STORM DRAINS,
BEFORE BEING PUMPED BACK INTO ANY STORMWATER SYSTEMS, WATER COURSES AND WATERS OF THE STATE (WOS) (NCDEQ) DIVISION OF WATER QUALITY (DWQ) GENERAL PERMIT - NCG 010000 TO DISCHARGE STORMWATER UNDER BASINS, OR STREAMS UNLESS NO ALTERNATIVE IS FEASIBLE.
OR WATERS OF THE UNITED STATES (WOU.S.). THE NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM FOR CONSTRUCTION ACTIVITIES. THE FINANCIALLY
RESPONSIBLE PARTY FOR THIS DEVELOPMENT IS RESPONSIBLE FOR MEETING THE REQUIREMENTS OF THE GENERAL 26. ANY OFF -SITE BORROW AND WASTE REQUIRED FOR THIS PROJECT MUST COME FROM A SITE WITH AN APPROVED
6. ALL EROSION CONTROL DEVICES SHALL BE PROPERLY MAINTAINED DURING ALL PHASES OF CONSTRUCTION UNTIL THE PERMIT. EROSION CONTROL PLAN, A SITE REGULATED UNDER THE MINING ACT OF 1971, OR A LANDFILL REGULATED BY THE
COMPLETION OF ALL CONSTRUCTION ACTIVITIES AND ALL DISTURBED AREAS HAVE BEEN STABILIZED. ADDITIONAL DIVISION OF SOLID WASTE MANAGEMENT. TRASH/DEBRIS FROM DEMOLITION ACTIVITIES OR GENERATED BY ANY
CONTROL DEVICES MAY BE REQUIRED DURING CONSTRUCTION IN ORDER TO CONTROL EROSION AND/OR OFFSITE 19. LITTER, CONSTRUCTION DEBRIS, OILS, FUELS AND BUILDING PRODUCTS WITH SIGNIFICANT POTENTIAL FOR IMPACT ACTIVITIES ON SITE MUST BE DISPOSED OF AT A FACILITY REGULATED BY THE DIVISION OF SOLID WASTE
SEDIMENTATION. ALL TEMPORARY CONTROL DEVICES SHALL BE REMOVED ONCE CONSTRUCTION IS COMPLETE AND (SUCH AS STOCKPILES OF FRESHLY TREATED LUMBER) AND CONSTRUCTION CHEMICALS THAT COULD BE EXPOSED TO MANAGEMENT OR PER DIVISION OF SOLID WASTE MANAGEMENT OR DIVISION OF WATER RESOURCES RULES AND
THE SITE IS STABILIZED. STORM WATER MUST BE PREVENTED FROM BECOMING A POLLUTANT SOURCE IN STORM WATER DISCHARGES. REGULATIONS.
7. THE CONTRACTOR MUST TAKE NECESSARY ACTION TO MINIMIZE THE TRACKING OF MUD ONTO PAVED ROADWAY 20. SHOW BMP MEASURES FOR CONCRETE TRUCK WASHOUT AREA, OR ADD THE FOLLOWING NOTES: 27. PER SECTION 6.20 OF THE NORTH CAROLINA EROSION AND SEDIMENT CONTROL PLANNING AND DESIGN MANUAL,
FROM CONSTRUCTION AREAS AND THE GENERATION OF DUST. THE CONTRACTOR SHALL DAILY REMOVE MUD/SOIL DIVERSIONS THAT WILL STAY IN PLACE LONGER THAN 30 WORKING DAYS SHOULD BE SEEDED AND MULCHED AS SOON
FROM PAVEMENT, AS MAY BE REQUIRED. CONCRETE TRUCKS SHALL NOT TYPICALLY BE WASHED OUT ON SITE. IF CONCRETE TRUCK WASHOUT IS PERMITTED AS THEY ARE CONSTRUCTED TO PRESERVE DIKE HEIGHT AND REDUCE MAINTENANCE.
ON SITE, COORDINATE LOCATION AND BMP'S WITH SITE INSPECTOR.
8. ALL CONSTRUCTION TRAFFIC SHALL ENTER AND EXIT THE SITE VIA THE CONSTRUCTION ENTRANCE.
DO NOT DISPOSE OF CONCRETE TRUCK WASHOUT WASTE BY DUMPING INTO A SANITARY SEWER, STORM DRAIN
9. EXCAVATED MATERIAL FROM TRENCHES SHALL BE PLACED ON THE UPGRADE SIDE OF THE TRENCH TO ALLOW OR ONTO SOIL OR PAVEMENT THAT CARRIES STORM WATER RUNOFF.
MATERIAL TO ERODE INTO THE TRENCH. CONSTRUCTION MAINTENANCE AND REMOVAL OF ALL EROSION CONTROL
DEVICES ARE THE RESPONSIBILITY OF GRADING CONTRACTOR UNLESS OTHERWISE NOTED.
GRAPHIC SCALE
30 0 15 30 60
( IN FEET)
1 inch = 30 ft.
LEGEND
WETLANDS
_SF SILT FENCE
-sF SF - SILT FENCE OUTLET
TP TREE PROTECTION FENCE
� M m m m � TRIBUTARY AREA
or LIMITS OF DISTURBANCE
ARK
ROCK CHECK DAM
INLET PROTECTION
GENERAL NOTES
1. ALL MATERIALS, CONSTRUCTION, AND PLANS ARE TO COMPLY WITH CURRENT
TOWN OF MT. PLEASANT AND NCDENR STANDARD SPECIFICATIONS AND
DETAILS.
2. CONTACT NORTH CAROLINA ONE CALL SERVICE @ 811 OR 800-632-4949 AND
TOWN OF MT. PLEASANT, A MINIMUM OF 72 HOURS BEFORE DIGGING.
3. ANY SITE GRADING SHALL COMPLY WITH INTENT OF ORIGINAL DEVELOPMENT
GRADING AND DRAINAGE PLANS.
4. THE CONTRACTOR SHALL VERIFY ALL EXISTING STRUCTURES PRIOR TO
CONSTRUCTION. ALL DISCREPANCIES SHALL BE REPORTED TO THE ENGINEER.
5. NO BMPS SHALL BE PLACED ON ADJACENT PROPERTY WITHOUT THE WRITTEN
CONSENT OF THE PROPERTY OWNER AND THE TOWN OF MT. PLEASANT.
6. THE NCDENR EROSION CONTROL MANUAL AND TOWN OF MT. PLEASANT
STANDARDS SHALL BE USED AS A GUIDELINE FOR IMPPLEMENTATION AND
MAINTENANCE OF BMPS. THE FOLLOWING BMPS:
• SURFACE ROUGHENING
• STABILIZED CONSTRUCTION ENTRANCE
• SILT FENCE
• HARDWARE FABRIC AND STONE INLET PROTECTION
• CHECK DAMS
• TEMPORARY SEEDING
• PERMANENT SEEDING
• MULCHING
• SOD
SITE INFO
CONSTRUCTION START DATE: AUGUST, 2019
DISTURBED AREA: 3.09 ACRES
CONSTRUCTION SEQUENCE
1. CONTRACTOR SHALL MEET WITH THE EROSION CONTROL INSPECTOR PRIOR
TO COMMENCING WITH PHASE 2 EROSION CONTROL MEASURES.
2. INSTALL REMAINING SILT FENCE, DIVERSION DITCHES AND OTHER MEASURES
AS SHOWN ON THE PHASE 2 PLANS, CLEARING ONLY AS NECESSARY TO
INSTALL THESE DEVICES.
3. CONTINUE MASS GRADING ACTIVITIES. AS SITE IS GRADED AND PADS BUILT
UP, CONTRACTOR SHALL MINIMIZE THE AMOUNT OF STORMWATER
FLOWING OVER FILL SLOPES BY USING DIVERSION DITCHES AND SLOPE
DRAINS. DITCHES AND SLOPE DRAINS SHOWN ON PLANS DEPICT THE
REQUIRED DIVERSION DITCHES AND SLOPE DRAINS AT FINAL PAD GRADE.
ADDITIONAL MEASURES MAY BE NEEDED AS GRADING PROGRESSES.
CONTRACTOR SHALL LIMIT DRAINAGE AREAS FLOWING TO EACH OF THE
PROPOSED BASINS TO THE MAXIMUM AREA THAT IS DESIGNATED FOR EACH
BASIN. THIS SHALL BE ACCOMPLISHED BY ADJUSTING THE PROPOSED
DIVERSION DITCHES AS THE SITE IS GRADED.
4. LIMIT CLEARING AND GRUBBING OF SITE TO AREAS THAT WILL BE MASS
GRADED. WHENEVER POSSIBLE, EXISTING VEGETATION SHALL REMAIN IN
PLACE TO PREVENT EROSION OF THE SITE.
5. CONSTRUCTION OF THE STREETS, THE ASSOCIATED UTILITIES, INCLUDING
LATERALS, TO THE COMPLETED AND INSPECTED.
6. RECONFIGURE SILT FENCE AS NECESSARY.
7. INSTALL INLET PROTECTION AND OTHER MEASURES AS SHOWN ON PHASE 2
PLANS AS THE PROPOSED STORM SYSTEM IS INSTALLED.
8. ALL AREAS THAT WILL GO UNWORKED FOR 14 DAYS OR MORE MUST BE
STABILIZED IMMEDIATELY. STABILIZATION STANDARDS SHOULD BE
MAINTAINED THROUGHOUTTHE CONSTRUCTION PROCESS.
9. STRIPPED TOPSOIL SHALL BE STOCKPILED IN DESIGNATED AREAS WITH SILT
FENCE PROVIDED AROUND THE PERIMETER OF THE STOCKPILE.
10. MAINTAIN AND ADJUST THE EROSION AND SEDIMENT CONTROL MEASURES
AS MASS GRADING PROGRESSES TO MAINTAIN PROPER EROSION AND
SEDIMENT CONTROL.
11. THE CONTRACTOR SHALL DILIGENTLY AND CONTINUOUSLY MAINTAIN ALL
EROSION CONTROL DEVICES AND STRUCTURES.
12. STABILIZE THE SITE AS AREAS ARE BROUGHT TO GRADE.
13. INSPECT BMPS ONCE PER EVERY CALENDAR WEEK, PER THE NCDEQ
REQUIREMENTS. ALL INSPECTION AND REPORTING SHALL BE IN COMPLIANCE
WITH THE NCDEQ GENERAL PERMIT NCGO10000, LATEST EDITION.
SOIL MAP LEGEND
E n D Enon Sandy Loam
E n B Enon Sandy Loam
_-
*** 3 Days Before Digging ***
- 0-07-19
North Carolina 811
811 or 1-800-632-4949
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STIPULATION FOR REUSE
THIS DRAWING WAS PREPARED FOR USE
ON A SPECIFIC SITE, SKYLAND DRIVE
TOWNHOMES, S. SKYLAND DRIVE, MT.
PLEASANT, NC, CONTEMPORANEOUSLY
WITH ITS ISSUE DATE ON 10/07/19. AND
IT IS NOT SUITABLE FOR USE ON A
DIFFERENT PROJECT SITE OR AT A LATER
TIME. USE OF THIS DRAWING FOR
REFERENCE OR EXAMPLE ON ANOTHER
PROJECT REQUIRES THE SERVICES OF
PROPERLY LICENSED ARCHITECTS AND
ENGINEERS. REPRODUCTION OF THIS
DRAWING FOR REUSE ON ANOTHER
PROJECT IS NOT AUTHORIZED AND MAY
BE CONTRARY TO THE LAW.
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MODIFICATION LOG
JOB NUMBER: C190010
CHECKED BY: BMF
DRAWN BY: BHE
DATE: 10-07-2019
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EROSION
CONTROL
PLAN PHASE 2
SHEET:
C791

R/v
� Rn,
INV; 666.2
R/W (PARTIALL r Bus
BURIED) N�G� SHEL TER
_R/W_- - R - - R/W - - R/W - - ��.R/W R/W7- R/W - R W/ R/W OE-OE-OEOEOE OE -0 --OF-R/WOE OE �OE� OE OE �9E DOE OE OE OE OE R/W OE -OE -OE$ --OE-
\ --�• _ \ ii DRIVE S•R• 2�57 --0=- =0E\ OE--OE--OE- -OE _ n -
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NAIL PP v v / s9.82
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S=2. % \ \ S=1.0% I S= A T a
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1 2 3-, 4 6 7 \ 8/ 9 10
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NOW OR FORMERLY
DB 7447, PG 58
5660-94-0591
TRACT I AND PART OF TRACT 2
1
997. SKYLAND ••
MT. PLEASANT, NC28124
ZONED "RL"
2
'all
I
- 680
1
2
13
14
15 T_
---16
SILT FENCE p.)
I
LIMITS
DISTU ANCE
I
NOW OR FORMERLY
JERRY R TUCKER &
ROSE P TUCKER
DB 12430, PG 49
PIN: 5660-95-6392
x /C \ \ U A R I E \ \\ I I \ TRACTI
INLET PR CTIO � � � 1 MB 72, PG 107
\ �� \ (7) V / (P16 . S{h B IC O 3435 HIGHWAY73 E
\ CONCORD,ZONED"RH"
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i
FREDA E. SHOE
\ x // DB 545, PG. 330
BMP ro PIN:5660-95-7144
SEESHIETC / / / / /\ / EXISTING POND I \ \ I I I I - I- I / I I
Ix \ \ LOTS 35 40
8, o 10OT
MT. PLEASANT, NC 28124
ZONED „RH„
X_
\X
_ R/�✓- f -/��� R/W -X - X /vn/ - o / - - R/W - R/W �- _ _ �R -� \ R/W - - -OE- - �R6 of - DE R6 of - -
X"" X X j X X X X X X X X X OE -- OE -- E- °E CONCRE7t
- \\\ \\ X x ,� 0-OE--7T i DRIVE
x /
/ABBOTT STREE / a % I
(40' PUBLIC R/W)
(PB 8/63, DB 350/510)
� � III II II II I II III w - w - �
M Jam' FM FM� FM
EROSION AND SEDIMENT CONTROL NOTES:
1. IF NECESSARY, SLOPES WHICH EXCEED EIGHT (8) FEET SHOULD BE STABILIZED WITH SYNTHETIC OR VEGETATIVE MAT, 10. THE EROSION CONTROL MEASURES SHOWN ON THIS DRAWING ARE RECOMMENDED AT A MINIMUM. ACTUAL CONCRETE TRUCK WASHOUT SHALL BE DISPOSED OF IN ACCORDANCE WITH THE FOLLOWING: /
IN ADDITION TO HYDROSEEDING. IT MAY BE NECESSARY TO INSTALL TEMPORARY SLOPE DRAINS DURING MEASURE NECESSARY FOR CONTAINMENT OF RUN-OFF SHALL BE THE RESPONSIBILITY OF THE CONTRACTOR AND BE I
\
CONSTRUCTION. TEMPORARY BERMS MAY BE NEEDED DAILY UNTIL THE SLOPE IS BROUGHT TO GRADE. FIELD VERIFIED. DESIGNATED AREA THAT WILL LATER BE BACKFILLED (SLURRY PIT) \\ RIM 690 77
DESIGNATED AREA WHERE CONCRETE WASH CAN HARDEN AND BE DISPOSED OF AS SOLID WASTE. I I �\ IINV: 685.12
2. STABILIZATION MEASURES SHALL BE INITIATED AS SOON AS PRACTICABLE IN PORTIONS OF THE SITE WHERE 11. ADDITIONAL MEASURES TO CONTROL EROSION AND SEDIMENT MAY BE REQUIRED BY A REPRESENTATIVE OF THE LOCATION THAT IS NOT SUBJECT TO WATER RUNOFF, AND MORE THAN 50 FEET AWAY FROM A STORM DRAIN, / o (HEAD of LINE)
CONSTRUCTION ACTIVITIES HAVE TEMPORARILY OR PERMANENTLY CEASED, BUT IN NO CASE MORE THAN FOURTEEN TOWN ENGINEERING DEPARTMENT. OPEN DITCH, OR RECEIVING WATER WAY. A
(14) DAYS AFTER WORK HAS CEASED, EXCEPT AS STATED BELOW: PUMP EXCESS CONCRETE IN CONCRETE PUMP BIN BACK INTO CONCRETE MIXER TRUCK. \ I W
12. SLOPES SHALL BE GRADED NO STEEPER THAN 2:1. FILL SLOPES GREATER THAN 10' REQUIRE ADEQUATE TERRACING. CONCRETE WASHOUT FROM CONCRETE PUMPER BINS CAN BE WASHED INTO CONCRETE PUMPER TRUCKS AND - of c,
ALL PERIMETER DIKES, SWALES, DITCHES, PERIMETER SLOPES AND ALL SLOPES STEEPER THAN 3 HORIZONTAL TO 1 DISCHARGED INTO DESIGNATED WASHOUT AREA OR PROPERLY DISPOSED OF OFFSITE. °E- - of
VERTICAL (3:1) SHALL BE PROVIDED TEMPORARY OR PERMANENT STABILIZATION WITH GROUND COVER AS SOON 13. A GRADING PLAN MUST BE SUBMITTED FOR ANY LOT GRADING EXCEEDING ONE ACRE THAT WAS NOT PREVIOUSLY
AS PRACTICABLE BUT IN ANY EVENT WITHIN 7 CALENDAR DAYS FROM THE LAST LAND -DISTURBING ACTIVITY. ALL APPROVED. 21. ALL CHEMICAL SPILLS, OIL SPILLS, OR FISH KILLS MUST BE REPORTED TO NCDEQ- CALL THE 24-HOUR EMERGENCY N M
OTHER DISTURBED AREAS SHALL BE PROVIDED TEMPORARY OR PERMANENT STABILIZATION WITH GROUND RESPONSE LINE AT 1-800-858-0368.
COVER AS SOON AS PRACTICABLE BUT IN ANY EVENT WITHIN 14 CALENDAR DAYS FROM THE LAST 14. ON -SITE BURIAL PITS ARE NOT ALLOWED, UNLESS WRITTEN APPROVAL IS RECEIVED FROM THE OWNER AND AN _\ LLI m oo
LAND -DISTURBING ACTIVITY. ON -SITE DEMOLITION LANDFILL PERMIT IS RECEIVED FROM THE ZONING ADMINISTRATOR. 22. TEMPORARY TOILET FACILITIES SHALL BE PROVIDED FOR ALL CONSTRUCTION WORKERS AND SITE VISITORS IN a a
ACCORDANCE WITH 2O06 INTERNATIONAL PLUMBING CODE GENERAL REGULATIONS, SECTION 311. PORTABLE I \ o o
3. ALL CUT AND FILL SLOPES AND CHANNEL SIDE SLOPES WHICH ARE NOT TO BE PAVED SHALL BE SEEDED UNTIL A GOOD 15. GRADING MORE THAN ONE ACRE WITHOUT AN APPROVED EROSION CONTROL PLAN IS A VIOLATION OF THE FACILITIES SHALL BE PLACED ON LEVEL GROUND AND AWAY FROM STORM DRAINAGE SYSTEMS (DITCHES, CATCH N W
STAND OF GRASS IS OBTAINED IN ACCORDANCE WITH THE SEEDING SCHEDULE ON SHEET C7.4. ALL SEEDING WILL BE TOWN/COUNTY EROSION CONTROL ORDINANCE AND IS SUBJECT TO A FINE. BASINS, ETC.). DISPOSAL AND HANDLING OF SANITARY WASTE MUST COMPLY WITH STATE AND LOCAL
MULCHED. REQUIREMENTS.
16. DRIVEWAY PERMIT FOR CONSTRUCTION ENTRANCES IN NCDOT RIGHT OF WAY MUST BE PRESENTED AT
4. ALL SEDIMENT AND EROSION CONTROL DEVICES SHALL BE INSPECTED EVERY SEVEN (7) DAYS AND WITHIN 24 HOURS PRE -CONSTRUCTION MEETING. 23. FINAL GRADES FOR GRASSED AND LANDSCAPED AREAS SHALL REQUIRE A MINIMUM OF 4-6" OF CLEAN TOP SOIL, FREE SSMH
AFTER EACH RAINFALL OCCURRENCE THAT EXCEEDS ONE-HALF (0.5) INCH. IF SITE INSPECTIONS IDENTIFY BMPS THAT OF DEBRIS AND CONTAMINANTS, AND PREFERABLY OF NATIVE ORIGIN. S RIM: 685.83
ARE DAMAGED OR NOT OPERATING EFFECTIVELY, MAINTENANCE MUST BE PERFORMED AS SOON AS PRACTICABLE OR
17. A FIREWORK MEETING SHALL BE SCHEDULED WITH THE TOWN INSPECTOR PRIOR TO CONSTRUCTION. �INV: 683.13
AS REASONABLY POSSIBLE AND BEFORE THE NEXT STORM EVENT WHENEVER PRACTICABLE. 24. SILT FENCE AND TREE PROTECTION SHOWN OFFSET FROM LIMITS OF DISTURBANCE FOR CLARIFICATION PURPOSES.
18. APPROVAL OF THE EROSION AND SEDIMENT CONTROL PLANS BY THE TOWN OF MT. PLEASANT GRANTS COVERAGE TO
5. IF WATER IS ENCOUNTERED WHILE TRENCHING, THE WATER SHOULD BE FILTERED TO REMOVE ANY SEDIMENTS THE DEVELOPMENT UNDER THE STATE OF NORTH CAROLINA DEPARTMENT OF ENVIRONMENTAL QUALITY RESOURCES 25. CONCRETE WASHOUT STATION AND STOCKPILES SHOULD NOT BE LOCATED WITHIN 50 FEET OF ANY STORM DRAINS,
BEFORE BEING PUMPED BACK INTO ANY STORMWATER SYSTEMS, WATER COURSES AND WATERS OF THE STATE (WOS) (NCDEQ) DIVISION OF WATER QUALITY (DWQ) GENERAL PERMIT - NCG 010000 TO DISCHARGE STORMWATER UNDER BASINS, OR STREAMS UNLESS NO ALTERNATIVE IS FEASIBLE.
OR WATERS OF THE UNITED STATES (WOU.S.). THE NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM FOR CONSTRUCTION ACTIVITIES. THE FINANCIALLY
RESPONSIBLE PARTY FOR THIS DEVELOPMENT IS RESPONSIBLE FOR MEETING THE REQUIREMENTS OF THE GENERAL 26. ANY OFF -SITE BORROW AND WASTE REQUIRED FOR THIS PROJECT MUST COME FROM A SITE WITH AN APPROVED
6. ALL EROSION CONTROL DEVICES SHALL BE PROPERLY MAINTAINED DURING ALL PHASES OF CONSTRUCTION UNTIL THE PERMIT. EROSION CONTROL PLAN, A SITE REGULATED UNDER THE MINING ACT OF 1971, OR A LANDFILL REGULATED BY THE
COMPLETION OF ALL CONSTRUCTION ACTIVITIES AND ALL DISTURBED AREAS HAVE BEEN STABILIZED. ADDITIONAL DIVISION OF SOLID WASTE MANAGEMENT. TRASH/DEBRIS FROM DEMOLITION ACTIVITIES OR GENERATED BY ANY
CONTROL DEVICES MAY BE REQUIRED DURING CONSTRUCTION IN ORDER TO CONTROL EROSION AND/OR OFFSITE 19. LITTER, CONSTRUCTION DEBRIS, OILS, FUELS AND BUILDING PRODUCTS WITH SIGNIFICANT POTENTIAL FOR IMPACT ACTIVITIES ON SITE MUST BE DISPOSED OF AT A FACILITY REGULATED BY THE DIVISION OF SOLID WASTE
SEDIMENTATION. ALL TEMPORARY CONTROL DEVICES SHALL BE REMOVED ONCE CONSTRUCTION IS COMPLETE AND (SUCH AS STOCKPILES OF FRESHLY TREATED LUMBER) AND CONSTRUCTION CHEMICALS THAT COULD BE EXPOSED TO MANAGEMENT OR PER DIVISION OF SOLID WASTE MANAGEMENT OR DIVISION OF WATER RESOURCES RULES AND
THE SITE IS STABILIZED. STORM WATER MUST BE PREVENTED FROM BECOMING A POLLUTANT SOURCE IN STORM WATER DISCHARGES. REGULATIONS.
7. THE CONTRACTOR MUST TAKE NECESSARY ACTION TO MINIMIZE THE TRACKING OF MUD ONTO PAVED ROADWAY 20. SHOW BMP MEASURES FOR CONCRETE TRUCK WASHOUT AREA, OR ADD THE FOLLOWING NOTES: 27. PER SECTION 6.20 OF THE NORTH CAROLINA EROSION AND SEDIMENT CONTROL PLANNING AND DESIGN MANUAL,
FROM CONSTRUCTION AREAS AND THE GENERATION OF DUST. THE CONTRACTOR SHALL DAILY REMOVE MUD/SOIL DIVERSIONS THAT WILL STAY IN PLACE LONGER THAN 30 WORKING DAYS SHOULD BE SEEDED AND MULCHED AS SOON
FROM PAVEMENT, AS MAY BE REQUIRED. CONCRETE TRUCKS SHALL NOT TYPICALLY BE WASHED OUT ON SITE. IF CONCRETE TRUCK WASHOUT IS PERMITTED AS THEY ARE CONSTRUCTED TO PRESERVE DIKE HEIGHT AND REDUCE MAINTENANCE.
ON SITE, COORDINATE LOCATION AND BMP'S WITH SITE INSPECTOR.
8. ALL CONSTRUCTION TRAFFIC SHALL ENTER AND EXIT THE SITE VIA THE CONSTRUCTION ENTRANCE.
DO NOT DISPOSE OF CONCRETE TRUCK WASHOUT WASTE BY DUMPING INTO A SANITARY SEWER, STORM DRAIN
9. EXCAVATED MATERIAL FROM TRENCHES SHALL BE PLACED ON THE UPGRADE SIDE OF THE TRENCH TO ALLOW OR ONTO SOIL OR PAVEMENT THAT CARRIES STORM WATER RUNOFF.
MATERIAL TO ERODE INTO THE TRENCH. CONSTRUCTION MAINTENANCE AND REMOVAL OF ALL EROSION CONTROL
DEVICES ARE THE RESPONSIBILITY OF GRADING CONTRACTOR UNLESS OTHERWISE NOTED.
GRAPHIC SCALE
30 0 15 30 60
( IN FEET )
1 inch = 30 ft.
LEGEND
WETLANDS
_SF SILT FENCE
-sF SF - SILT FENCE OUTLET
TP TREE PROTECTION FENCE
� M m m m � TRIBUTARY AREA
or LIMITS OF DISTURBANCE
ARK
ROCK CHECK DAM
INLET PROTECTION
GENERAL NOTES
1. ALL MATERIALS, CONSTRUCTION, AND PLANS ARE TO COMPLY WITH CURRENT
TOWN OF MT. PLEASANT AND NCDENR STANDARD SPECIFICATIONS AND
DETAILS.
2. CONTACT NORTH CAROLINA ONE CALL SERVICE @ 811 OR 800-632-4949 AND
TOWN OF MT. PLEASANT, A MINIMUM OF 72 HOURS BEFORE DIGGING.
3. ANY SITE GRADING SHALL COMPLY WITH INTENT OF ORIGINAL DEVELOPMENT
GRADING AND DRAINAGE PLANS.
4. THE CONTRACTOR SHALL VERIFY ALL EXISTING STRUCTURES PRIOR TO
CONSTRUCTION. ALL DISCREPANCIES SHALL BE REPORTED TO THE ENGINEER.
5. NO BMPS SHALL BE PLACED ON ADJACENT PROPERTY WITHOUT THE WRITTEN
CONSENT OF THE PROPERTY OWNER AND THE TOWN OF MT. PLEASANT.
6. THE NCDENR EROSION CONTROL MANUAL AND TOWN OF MT. PLEASANT
STANDARDS SHALL BE USED AS A GUIDELINE FOR IMPPLEMENTATION AND
MAINTENANCE OF BMPS. THE FOLLOWING BMPS:
• SURFACE ROUGHENING
• STABILIZED CONSTRUCTION ENTRANCE
• SILT FENCE
• HARDWARE FABRIC AND STONE INLET PROTECTION
• CHECK DAMS
• TEMPORARY SEEDING
• PERMANENT SEEDING
• MULCHING
• SOD
SITE INFO
CONSTRUCTION START DATE: AUGUST, 2019
DISTURBED AREA: 3.09 ACRES
CONSTRUCTION SEQUENCE
1. CONTRACTOR SHALL MEET WITH THE EROSION CONTROL INSPECTOR PRIOR
TO COMMENCING WITH PHASE 3 EROSION CONTROL MEASURES.
2. INSTALL ANY REMAINING SILT FENCE, DIVERSION DITCHES AND OTHER
MEASURES AS SHOWN ON THE PHASE 3 PLANS, CLEARING ONLY AS
NECESSARY TO INSTALL THESE DEVICES.
3. TOWNHOME CONSTRUCTION SHALL COMMENCE. CONTRACTOR TO INSTALL
ANY ADDITIONAL EROSION CONTROL MEASURES FOR THE INDIVIDUAL LOT
CONSTRUCTION.
4. CONTRACTOR TO ENSURE THAT OCCUPIED HOMES BE PROTECTED FROM
EROSION AND SEDIMENT FROM THE REMAINDER OF THE SITE.
5. FINALIZE GRADING ACTIVITIES.
6. LIMIT CLEARING AND GRUBBING OF THE SITE TO AREAS THAT WILL BE MASS
GRADED. WHENEVER POSSIBLE, EXISTING VEGETATION SHALL REMAIN IN
PLACE TO PREVENT EROSION OF THE SITE.
7. ALL AREAS THAT GO UNWORKED FOR 14 DAYS OR MORE MUST BE
STABILIZED IMMEDIATELY. STABILIZATION STANDARDS SHALL BE
MAINTAINED THROUGHOUTTHE CONSTRUCTION PROCESS.
8. MAINTAIN AN ADJUST EROSION AND SEDIMENT CONTROL MEASURES AS
GRADING AND CONSTRUCTION PROGRESSES.
9. THE CONTRACTOR SHALL DILIGENTLY AND CONTINUOUSLY MAINTAIN ALL
EROSION CONTROL DEVICES AND STRUCTURES.
10. STABILIZE SITE AS AREAS ARE BROUGHT TO GRADE.
11. COORDINATE WITH EROSION CONTROL INSPECTOR PRIOR TO REMOVAL OF
EROSION CONTROL MEASURES. UPON INSPECTOR'S APPROVAL, CONTRACTOR
IS TO REMOVE ALL EROSION CONTROL MEASURES, INCLUDING ANY
APPROVED SEDIMENT BASINS.
12. CONVERSION OF SEDIMENT BASINS TO PERMANENT STORMWATER BASINS
TO BE COMPLETED PER APPROVED CONSTRUCTION PLANS. BRING AREAS
OUTSIDE OF PERMANENT STORMWATER BASINS, PREVIOUSLY OCCUPIED BY
SEDIMENT BASINS AND ASSOCIATED GRADING TO FINISHED GRADE OR
WHERE APPLICABLE BACK TO THE APPROXIMATE EXISTING GRADE AND
REPLANTED.
13. ALL EROSION CONTROL MEASURES SHALL BE CONSTRUCTED IN ACCORDANCE
WITH NCDEQ STANDARDS.
14. WHEN VEGETATION IS ESTABLISHED, CALL FOR FINAL SITE INSPECTION AND
FILE A NOTICE OF TERMINATION WITH THE TOWN OF MT. PLEASANT/NCDEQ.
SOIL MAP LEGEND
E n D Enon Sandy Loam
E n B Enon Sandy Loam
I �
1
*** 3 Days Before Digging ***
North Carolina 811
811 or1-800-632-4949
Remote Ticket Entry
http://nc8 I I .org/remoteticketentry.htm
STIPULATION FOR REUSE
THIS DRAWING WAS PREPARED FOR USE
ON A SPECIFIC SITE, SKYLAND DRIVE
TOWNHOMES, S. SKYLAND DRIVE, MT.
PLEASANT, NC, CONTEMPORANEOUSLY
WITH ITS ISSUE DATE ON 10/07/19. AND
IT IS NOT SUITABLE FOR USE ON A
DIFFERENT PROJECT SITE OR AT A LATER
TIME. USE OF THIS DRAWING FOR
REFERENCE OR EXAMPLE ON ANOTHER
PROJECT REQUIRES THE SERVICES OF
PROPERLY LICENSED ARCHITECTS AND
ENGINEERS. REPRODUCTION OF THIS
DRAWING FOR REUSE ON ANOTHER
PROJECT IS NOT AUTHORIZED AND MAY
BE CONTRARY TO THE LAW.
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MODIFICATION LOG
JOB NUMBER: C190010
CHECKED BY: BMF
DRAWN BY: BHE
DATE: 10-07-2019
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EROSION
CONTROL
PLAN PHASE 3
SHEET:
C71

PLAN VIEW
SKIMMER SEDIMENT BASIN
DESIGN CRITERIA
DRAINAGE
AREA
< 10 AC.
(ACRES)
LENGTH
Y-:-:
MIN.
I
LENGTH TO
2:1
INFLOW
WIDTH RATIO
10,
MIN.
MAX.
I-
-
LENGTH TO
61
WIDTH RATIO
SKIMMER
DEWATERING
MIN.
1800
AVERAGE- AREA*
DEVICE
VOLUME
(CU. FT.
WIDTH LENGTH
REQUIRED
PER AC.
DISTURBED)
AREA OF BASIN WATER SURFACE
AT TOP OF PRIMARY SPILLWAY
325
L
SKAREA
(SQ. FT. PER
CFS Q10)R
CROSS-SECTION VIEW
BAFFLES
(CLDS
#30.19) V FREEBOARD
VV-S MIN.
6" MAX. DEPTH OF FLOW OVER
INFLOW BAFFLES
EMERGENCY SPILLWAY
Z=5' MAX.
DEWATERING
ZONE
_/,
- -
Z;
H=2' MIN.
1 11
FILTER FABRIC
CLEANOUT
SKIMMER ARM
DEPTH
LENGTH=
(H/2) V SEDIMENT
H x 1.5
STORAGE
(MIN. 5')
DATA BLOCK
NOTES:
1. REFER TO NCESCPDM
SECTION #6.64 FOR
ADDITIONAL DESIGN
EMBANKMENT SPECIFICATIONS
REGARDING SKIMMER
SEDIMENT BASINS.
2. REFER TO BAFFLE
INSTALLATION DETAIL FO
BAFFLE SPACING AND
INSTALLATION.
3. TURBIDITY CURTAIN MAY
BE USED IN LIEU OF
POROUS BAFFLES.
4. SKIMMER INVERT
ELEVATION = BASIN
EMERGENCY BOTTOM + 1' MIN.
SPILLWAY
5. H = SPILLWAY ELEVATION -
SKIMMER INVERT
ELEVATION
- EMBANKMENT
T=1.5' MIN.
EMERGENCY
SPILLWAY
- SPECIFY
SEEPAGE
CONTROL NOT TO SCALE
MEASURES
PHASE
BASIN
DRAINAGE
AREA
(ACRES)
DENUDED
AREA
(ACRES)
Q10
(CFS)
BASIN VOLUME
SURFACE AREA
CLEANOUT
DEPTH H/2
(FT)
H
(FT)
Z
(FT)
L
(FT)
T
(FT)
W
(FT)
SKIMMER
PIPE
DIA.
SKIMMER
ORIFICE
DIA.
REQUIRED
(CF)
PROVIDED
(CF)
REQUIRED
(SF)
PROVIDED
(SF)
1
2
1.17
1.05
3.94
2,106
3,065
1,282
1 1,840
1
2.00
4
20
1.5
5
2
0.90
PVC EN
PVC
SKIMMER SEDIMENT BASIN
N.T.S.
BACKFILL AND COMPACT
FENCE AND FABRIC
BURIED IN TRENCH
BAFFLE INSTALLATION
N.T.S.
PERSPECTIVE VIEW
END VIEW
PVC VENT
FRONT VIEW
GENERAL NOTES:
1. DRIVE 5' STEEL POST AT LEAST
24" INTO SOLID GROUND.
2. USE STAPLES 1' APART
HORIZONTALLY AND VERTICALLY
TO ATTACH THE FILTER FABRIC
TO THE WIRE FENCE.
3. MINIMUM BAFFLE SPACING IS 10'.
4. THE FLOOR OF THE BASIN IN
THE OUTLET ZONE AND BERMS
SHOULD BE SEEDED
IMMEDIATELY AFTER THE BASIN
IS CONSTRUCTED.
5. REFER TO NCESCPDM SECTION
#6.65 FOR ADDITIONAL
SPECIFIATIONS.
"C" ENCLOSURE
%TFR FNTRY HNIT
SCHEMATIC OF SKIMMER TAKEN FROM PENNSYLVANIA EROSION AND SEDIMENT POLLUTION CONTROL MANUAL, MARCH 2O00.
SEDIMENT BASIN SKIMMER
N.T.S.
onu 11 E 40
SEDIMENT BASIN
DESIGN CRITERIA
DRAINAGE
AREA
>10 AC.
(ACRES)
<100 AC.
MIN.
LENGTH TO
2:1
WIDTH RATIO
MAX.
LENGTH TO
6:1
WIDTH RATIO
1800
MIN.
(CU. FT.
VOLUME
PER AC.
REQUIRED
DISTURBED)
435
SURFACE
(SQ. FT. PER
AREA
CFS Q10)
REQUIRED
PLAN VIEW
INFLOW
STRUCTURE
AVERAGE AREA*
WIDTH W =
L
* AREA OF BASIN WATER SURFACE
AT TOP OF PRINCIPAL SPILLWAY
CROSS-SECTION VIEW
INFLOW
STRUCTURE
amm
DEWATERING
ZONE
FILTER FABRIC
SEDIMENT
STORAGE ZONE
DATA BLOCK
SEE NOTE #3
V FREEBOARD
6" MIN. INVERT ELEVATION
OF EMERGENCY SPILLWAY
PRIMARY SPILLWAY
2' MIN(RISER)
14
BAFFLE
GENTLE SLOPES STEEP SLOPES
3RD BAFFLE:
HARDWARE
CLOTH
100 Ibs/acre tall fescue
SURROUNDING
SEEDING
30lbs/acre Sericea lespedeza
SKIMMER
NOTES:
MIXTURE
80 Ibs/acre of tall fesue (unscarified after August 15)
10 Ibs/acre Kobe lespedeza
1. REFER TO NCESCPDM
SECTION #6.61 FOR
FALL: August 25 - October FALL: August 25 - October 15
ADDITIONAL DESIGN
SPECIFICATIONS
Late winter: February 15 -April 15 Late winter: February 15 -April 15
REGARDING SEDIMENT
BASINS.
SEEDING
To extends spring seeding into June, add To extends spring seeding into June, add
p� 9 9� p� 9 9
15 Ibs/acre hulled Bermudagrass 15 Ibs/acre hulled Bermudagrass
DATES
-
2. REFER TO BAFFLE
INSTALLATION DETAIL FOR
Overseeding of Kobe lespedeza over fall -seeded Overseeding of Kobe lespedeza over fall -seeded
RISER
BAFFLE SPACING AND
tall fescue is very effective. tall fescue is very effective.
INSTALLATION.
3. FIRST BAFFLE IS TO BE
SEEDING
Apply lime and fertilizer per soil rests, or 4000 Apply lime and fertilizer per soil rests, or 4000
CONSTRUCTED OF
AMENDMENTS
Ibs/acre limestone and 1000 Ibs/acre 10-10-10 Ibs/acre limestone and 1000 Ibs/acre 10-10-10
RIP -RAP AND #5 WASHED
fertilizer. fertilizer.
STONE, WITH A MIN.
L=20'
HEIGHT OF 3' AND MIN.
MIN.
TOPWIDTH OF 2'.
NOTE 1
Ground Cover-- Protective cover must be established on all disturbed areas within 21 calendar days after
4. FLASHBOARD RISER NOT
land disturbing activity is completed or has temporarily ceased.
PERMITTED FOR USE
NOTE 2
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Graded slopes and fills-- Protective cover must be established on all graded slopes and fills within 21 calendar days after
a phase of grading is completed or has temporarily ceased.
FEMBANKMENT
iT
SEEDING SCHEDULE
EMERGENCY
SPILLWAY
ANTI -SEEP
COLLAR NOT TO SCALE
PHASE
BASIN
DRAINAGE
AREA
(ACRES)
DENUDED
AREA
(ACRES)
Q10
(CFS)
BASIN VOLUME
SURFACE AREA
CLEANOUT
DEPTH H/2
(FT)
H
(FT)
Z
(FT)
L
(FT)
T
(FT)
W
(FT)
SKIMMER
PIPE
DIA.
SKIMMER
ORIFICE
DIA.
REQUIRED
(CF)
PROVIDED
(CF)
REQUIRED
(SF)
PROVIDED
(SF)
1
1
1.10
1.03
3.87
1,980
10,435
1,682
4,638
1.4
2.80
6
35
83.2
10
2
1.00
2
1 1
1 1.62
1 1.56
1 5.69
2,916
10,435
1 2,477
4,638
1 1.4
1 2.80
1 6
1 35
1 83.7
1 10
2
1.00
SEDIMENT BASIN
N.T.S.
GENERAL NOTES:
1. AREA UNDER EMBANKMENT SHALL BE CLEARED, GRUBBED, AND STRIPPED OF ANY VEGETATION AND ROOT MATERIAL. THE BASIN AREA SHALL BE CLEARED.
2. THE FILL MATERIAL FOR THE EMBANKMENT SHALL BE FREE OF ROOTS OR OTHER WOODY VEGETATION AS WELL AS OVERSIZED STONES, ROCKS, ORGANIC
MATERIAL OR OTHER OBJECTIONABLE MATERIAL. THE EMBANKMENT SHALL BE COMPACTED BY TRAVERSING WITH EQUIPMENT WHILE BEING CONSTRUCTED.
SPILLWAYS SHOULD NOT BE CONSTRUCTED THROUGH FILL SECTIONS. ALL SPILLWAYS SHOULD BE LINED AND/OR RIPRAPPED.
3. SEDIMENT SHALL BE REMOVED AND TRAP RESTORED TO ITS ORIGINAL DIMENSIONS WHEN THE SEDIMENT HAS ACCUMULATED TO DEPTH SHOWN ON STANDARD.
REMOVED SEDIMENT SHALL BE DEPOSITED IN A SUITABLE AREA IN SUCH A MANNER THAT IT WILL NOT ERODE.
4. THE TRAP SHALL BE INSPECTED AFTER EACH RAIN AND REPAIRS MADE AS NECESSARY.
5. CONSTRUCTION OPERATION SHALL BE CARRIED OUT IN SUCH A MANNER THAT EROSION AND WATER POLLUTION IS MINIMIZED.
6. ALL CUT AND FILL SLOPES SHALL BE 2:1 OR FLATTER, UNLESS CERTIFIED BY REGISTERED GEOTECHICAL ENGINEER.
7. SEDIMENT BASIN EMBANKMENTS SHOULD BE PROVIDED WITH EROSION CONTROL AND STABILIZATION.
8. STORAGE AREA IS SHOWN AS RECTANGULAR FOR ILLUSTRATIVE PURPOSES ONLY, AND MAY BE CONSTRUCTED IN ANY SHAPE PROVIDED THE MINIMUM STORAGE
VOLUME REQUIREMENT IS MET. THE BASIN SHOULD ALSO BE ORIENTED SUCH THAT THE FILTER AND THE MAIN FLOW OF WATER AND SEDIMENT ARE ON
OPPOSITE ENDS ON THE LONGER BASIN DIMENSIONS.
9. REQUIRED STORAGE IS 1800 CUBIC FEET OF STORAGE VOLUME PER ACRES OF DRAINAGE AREA. IF CLEAR WATER FROM UNDISTURBED AREAS IN DRAINAGE BASIN
ARE TAKEN AROUND OR THROUGH THE DENUDED AREA BY NON EROSIVE MEASURES THEN BASINS MAY BE SIZED BY DENUDED ACRES. RECOMMENDED
STORAGE IS 1800 CUBIC FEET OF STORAGE PER ACRE OF DRAINAGE AREA.
10.THE LENGTH OF THE STONE OUTLET (SPILLWAY) IS TO BE BASED ON A 10 YEAR STORM.
11. WHENEVER TOPOGRAPHY ALLOWS, THE BASIN LENGTH SHOULD BE TWICE (2X) THE BASIN WIDTH, TO ALLOW FOR SETTLING. BAFFLES SHALL BE INSTALLED IN
ALL BASINS.
12.CLEANOUT STAKES SHALL BE PLACED IN ALL SEDIMENT BASINS AT THE LOW POINT IN THE BASIN. THE STAKES SHALL BE MARKED SHOWING THE HALF FULL,
CLEANOUT POINT, OF THE BASIN.
13.SAFETY FENCING 3' HIGH SHOULD BE PLACED AROUND ALL SEDIMENT BASINS.
14.FOR DESIGN OF RISER TYPE SEDIMENT BASINS, REFER TO THE NORTH CAROLINA DEPARTMENT OF ENVIRONMENT, HEALTH, AND NATURAL RESOURCES, EROSION
AND SEDIMENT CONTROL PLANNING AND DESIGN MANUAL,
15.FOR SLOPES GREATER THAN 10' IN LENGTH AND PROTECTED BY SILT FENCE AT THE TOE OF THE SLOPE, SLOPE TERRACING WILL BE REQUIRED.
16.THE BERM ON SEDIMENT BASINS SHALL BE SEEDED ONCE FINAL GRADE HAS BEEN REACHED. THE SILT FENCE MAY BE REMOVED IF PERMISSION HAS BEEN
GRANTED BY THE CITY LAND DEVELOPMENT INSPECTOR AFTER THE GRASS HAS GERMINATED AND STABLE GROUND HAS BEEN ESTABLISHED.
17. WASHED STONE AND WIRE BACKING SHALL BE USED WITH SILT FENCE WHENEVER SILT FENCE IS PLACE AT THE TOE OF A SLOPE >10' VERTICAL OR ALONG ANY
CHANNEL OR WATER COURSE WHERE 50' OF BUFFER IS NOT PROVIDED.
SEDIMENT BASIN GENERAL NOTES
N.T.S.
NOTES:
1. CLASS OR MEDIAN SIZE OF RIPRAP AND LENGTH, WIDTH AND DEPTH OF APRON
TO BE DESIGNED BY THE ENGINEER.
RIPRAP SHOULD EXTEND UP BOTH SIDES OF THE APRON AND AROUND THE END
OF THE PIPE OR CULVERT AT THE DISCHARGE OUTLET AT A MAXIMUM SLOPE OF
2:1 AND A HEIGHT NOT LESS THAN TWO THIRDS THE PIPE DIAMETER OR
CULVERT HEIGHT.
3. THERE SHALL BE NO OVERFLOW FROM THE END OF THE APRON TO THE
SURFACE OF THE RECEIVING CHANNEL. THE AREA TO BE PAVED OR RIPRAPPED
SHALL BE UNDERCUT SO THAT THE INVERT OF THE APRON SHALL BE AT THE
SAME GRADE (FLUSH) WITH THE SURFACE OF THE RECEIVING CHANNEL. THE
APRON SHALL HAVE A CUTOFF OR TOE WALL AT THE DOWNSTREAM END.
4. THE WIDTH OF THE END OF THE APRON SHALL BE EQUAL TO THE BOTTOM
WIDTH OF THE RECEIVING CHANNEL. MAXIMUM TAPER TO RECEIVING CHANNEL 51
5. ALL SUBGRADE FOR STRUCTURE TO BE COMPACTED TO 95% OR GREATER.
6. THE PLACING OF FILL, EITHER LOOSE OR COMPACTED IN THE RECEIVING
CHANNEL SHALL NOT BE ALLOWED.
7. NO BENDS OR CURVES IN THE HORIZONTAL ALIGNMENT OF THE APRON
WILL BE PERMITTED.
8. FILTER FABRIC SHALL BE INSTALLED ON COMPACTED SUBGRADE PRIOR TO
PLACEMENT OF RIP RAP.
9. ANY DISTURBED AREA FROM END OF APRON TO RECIEVING CHANNEL
MUST BE STABILIZED.
USE USDA NOMOGRAPH FROM NC SEDIMENT AND EROSION CONTROL MANUAL FOR DESIGN DATA.
NATURAL GRADE
d50 (see fig 8.06 a&b "NC SEDIMENT AND EROSION CONTROL MANUAL"
dmax = 1.5 x d50
T = 1.5 X dmax.
RIPRAP APRON AT PIPE OUTFALLS
PLAN
(IF NEEDED)
ELEVATION
MINIMUM H=2/3 PIPE DIAMETER
THICKNESS)
TEMPORARY SEEDING FOR WARM AND COOL SEASON
EARLY SUMMER SEASON STEEP SLOPES
SEEDING
40 Ibs/acre of German millet
120 Ibs/acre Rye (grain)
MIXTURE
80 Ibs/acre oftall fesue
80 Ibs/acre tall fesue
May 1 -August 15
October 25 - December 30
SEEDING
Refertilize if growth is not fully adequate.
Between December 30 - February 15,
add 50 Ibs/acre of annual Kobe lespedeza.
DATES
Apply 4000 Ibs/acre straw or equivalent
Apply 4000 Ibs/acre straw or equivalent
hydroseeding.
hydroseeding.
SEEDING
Apply lime and fertilizer per soil rests, or 2000
Apply lime and fertilizer per soil rests, or 2000
AMENDMENTS
Ibs/acre limestone and 750 Ibs/acre 10-10-10
Ibs/acre limestone and 750 Ibs/acre 10-10-10
fertilizer.
fertilizer.
SEEDING SCHEDULE
(SEASONAL)
SEEDING SCHEDULES
N.T.S.
GENERAL NOTES:
1. RIPRAP SIZE TO BE DESIGNED BY ENGINEER.
2. CHECK DAMS MAYBE USED IN SLOPING DITCHES 2
OR CHANNELS TO SLOW VELOCITY OR TO CREATE CLASS B RIP RAP 1
SEDIMENT TRAPS.
3. ENSURE THAT MAXIMUM SPACING BETWEEN DAMS PLACES THE
TOE OF THE UPSTREAM DAM AT THE SAME ELEVATION AS THE
DOWNSTREAM DAM (SEE DIAGRAM BELOW).
70.0' B
A AND B ARE AT EQUAL ELEVATIONS
V-6" MIN.
PLAN
TEMPORARY ROCK CHECK DAM
N.T.S.
V-6" MIN.
# 5 WASHED STONE
iS,-JrLvvv 2' MAX
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CROSS SECTION
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STIPULATION FOR REUSE
THIS DRAWING WAS PREPARED FOR USE
ON A SPECIFIC SITE, SKYLAND DRIVE
TOWNHOMES, S. SKYLAND DRIVE, MT.
PLEASANT, INC, CONTEMPORANEOUSLY
WITH ITS ISSUE DATE ON 4/12/19. AND
IT IS NOT SUITABLE FOR USE ON A
DIFFERENT PROJECT SITE OR AT A LATER
TIME. USE OF THIS DRAWING FOR
REFERENCE OR EXAMPLE ON ANOTHER
PROJECT REQUIRES THE SERVICES OF
PROPERLY LICENSED ARCHITECTS AND
ENGINEERS. REPRODUCTION OF THIS
DRAWING FOR REUSE ON ANOTHER
PROJECT IS NOT AUTHORIZED AND MAY
BE CONTRARY TO THE LAW.
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MODIFICATION LOG
JOB NUMBER: C190010
CHECKED BY: BMF
DRAWN BY: BHE
DATE: 4-12-2019
[99£-0 # N&-j
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EROSION
CONTROL
DETAILS
N.T.S.
SHEET: C793

HOOD
GRATE
1" REBAR FOR BAG
REMOVAL FROM INLET
FILTER BAG
DUMP LOOPS
CATCH BASIN
SECTION
NOTES
1. INLET MAINTENANCE SHALL BE DOCUMENTED IN PROJECT LOG BOOK.
2. FILTER TYPES SHALL BE APPROVED BY THE TOWN INSPECTOR PRIOR
TO INSTALLATION.
3. FILTER BAGS MAY BE REMOVED WHEN SITE IS STABILIZED AT
THE DIRECTION OF THE ENGINEER.
4. FILTER BAGS SHALL BE REMOVED PRIOR TO STREET ACCEPTANCE.
5. FILTER BAGS SHALL BE CLEANED OR REPLACED ON A REGULAR
BASIS (NOT BE MORE THAN HALF FULL AT ANY TIME).
6. FILTER BAGS SHALL NOT BE ALLOWED IN EXISTING TOWN OR NCDOT
ROADS.
CATCH BASIN INLET PROTECTION
N.T.S.
DEFLECTOR
36" MIN. SPACING TYP.*
CUTLET
I N STA L LAT I O N
NOTE:
1. DITCH SHOULD HAVE LONGITUDINAL SLOPE OF 1%.
2. SILT FENCE MAY BE REQUIRED BEHIND BERM
TEMPORARY SILT DITCH
N.T.S.
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NOTES
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PROVIDE TURNING RADIUS SUFFICIENT TO ACCOMMODATE LARGE
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2.
LOCATE ENTRANCES TO PROVIDE FOR UTILIZATION
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3.
MUST BE MAINTAINED IN A CONDITION WHICH WILL PREVENT
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TRACKING OR DIRECT FLOW OF MUD ONTO STREETS.
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PERIODIC TOPDRESSING WITH STONE WILL BE NECESSARY.
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4.
ANY MATERIAL TRACKED ONTO THE ROADWAY MUST BE
CLEANED UP IMMEDIATELY.
5.
LOCATE GRAVEL CONSTRUCTION ENTRANCE AT ALL POINTS OF
INGRESS AND EGRESS UNTIL SITE IS STABILIZED. PROVIDE
FREQUENT CHECKS OF THE DEVICE AND TIMELY MAINTENANCE.
6.
NUMBER AND LOCATION OF CONSTRUCTION ENTRANCES TO
W
BE DETERMINED BY THE ENGINEER.
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7.
USE CLASS 'A' STONE OR OTHER COARSE AGGREGATE APPROVED
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BY THE ENGINEER.
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B.
INSTALL CONSTRUCTION ENTRANCES IN A WAY TO PREVENT VEHICLES
FROM BYPASSING CONSTRUCTION ENTRANCE LEAVING PROJECT SITE.
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NOTE:
PLACE GEOTEXTILE FOR DRAINAGE BENEATH STONE
SHEET 1 OF 1
1607.01
12" MIN.
114- SPACING TYP.*
t t t t t
t t
t
t
t
t
t t
\ t
/1 t
t
t
JMET WATER TABLE
L 6"
OVERLAP
IN SLICE
KEY/ANCHOR MATERIAL AT
TOP OF SLOPE.
GENERAL NOTES:
1. LAY BLANKETS LOOSELY AND STAKE
OR STAPLE TO MAINTAIN DIRECT
CONTACT WITH THE SOIL. DO NOT
STRETCH.
2. * DIMENSIONS SHOWN ARE MINIMUM,
MANUFACTURED PRODUCTS MAY
HAVE ADDITIONAL REQUIREMENTS
THAT MUST BE MET.
3. SLOPE SURFACE SHALL BE FREE OF
ROCKS, SOIL CLODS, STICKS, GRASS.
MAT/BLANKETS SHALL HAVE GOOD
SOIL CONTACT.
4. THE DETAIL SHOWN IS FOR SLOPE
MATTING. FOR CHANNEL OR PIPE
OUTFALL MATTING SPECIFICATIONS,
PLEASE REFER TO NCESCPDM
STANDARD #6.17 AND
MANUFACTURER'S GUIDELINES.
NON -WOVEN GEOTEXTILE FILTER CLOTH
FABRIC 4' ABOVE SOURCE WATER.
KEY/ANCHOR MATERIAL TO TOE OF SLOPE.
EMBANKMENT MATTING DETAIL
V MAX.
WOVEN FILTER FABRIC
0
N
GENERAL NOTES:
N.T.S.
1. WOVEN FILTER FABRIC BE USED WHERE SILT FENCE IS TO REMAIN FOR A PERIOD OF MORE THAN 30
DAYS.
2. STEEL POSTS SHALL BE T-0" IN HEIGHT AND BE OF THE SELF -FASTENER ANGLE STEEL TYPE.
3. TURN SILT FENCE UP SLOPE AT ENDS.
4. ORANGE SAFETY FENCE IS REQUIRED AT BACK OF SILT FENCE WHEN GRADING IS ADJACENT TO SWIM
BUFFERS, STREAMS OR WETLANDS (REFER TO SWIM BUFFER GUIDELINES). THE COLOR ORANGE IS
RESERVED FOR VISUAL IDENTIFICATION OF ENVIRONMENTALLY SENSITIVE AREAS.
5. DRAINAGE AREA CAN NOT BE GREATER THAN 1/4 ACRE PER 100 FT OF FENCE.
6. SLOPE LENGTHS CAN NOT EXCEED CRITERIA SHOWN IN TABLE 6.62A NORTH CAROLINA EROSION AND
SEDIMENT CONTROL PLANNING AND DESIGN MANUAL.
7. DO NOT INSTALL SEDIMENT FENCE ACROSS STREAMS, DITCHES, WATERWAYS OR OTHER AREAS OF
CONCENTRATED FLOW.
SILT FENCE
N.T.S.
STEEL POST
z_ FILTER FABRIC
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4 MIN.
MAINTENANCE NOTES:
1. FILTER BARRIERS SHALL BE INSPECTED BY THE FINANCIALLY RESPONSIBLE PARTY OR HIS
AGENT IMMEDIATELY AFTER EACH RAINFALL AND AT LEAST DAILY DURING PROLONGED
RAINFALL. ANY REPAIRS NEEDED SHALL BE MADE IMMEDIATELY.
2. SHOULD THE FABRIC DECOMPOSE OR BECOME INEFFECTIVE PRIOR TO THE END OF THE
EXPECTED USABLE LIFE AND THE BARRIER STILL IS NECESSARY, THE FABRIC SHALL BE
REPLACED PROMPTLY.
3. SEDIMENT DEPOSITS SHOULD BE REMOVED WHEN DEPOSITS REACH APPROX. HALF THE
HEIGHT OF THE BARRIER. ANY SEDIMENT DEPOSITS REMAINING IN PLACE AFTER THE SILT
FENCE IS REMOVED SHALL BE DRESSED TO CONFORM TO THE EXISTING GRADE, PREPARED
AND SEEDED.
LENGTH AS NECESSARY
TO GO THRU DIKE
4' MIN.
1.5' MIN. 1 r2
FLEXIBLE PIPE
TIE DOWN 10' MAX. SPACING
TIE DOWN AT END
4' (MIN)' i
* AT LESS THAN 1 % SLOPE
DIAMETER (D)
PIPE
RIP -RAP AP
I� <tlq►l�lCUgKelxi7��7691�1:
RIP RAP & WASHED STONE
FILTER BERM
-SEDIMENT PIT
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STAKES' -
' EARTH DIKE
CONSTRUCTION SPECIFICATIONS:
1. THE TOP OF THE EARTH DIKE OVER THE INLET PIPE AND THOSE
DIKES CARRYING WATER TO THE PIPE SHALL BE AT LEAST 1.5 FEET
HIGHER AT ALL POINTS THAN THE TOP OF THE INLET PIPE.
2. THE PIPE SHALL BE FLEXIBLE WITH WATER TIGHT CONNECTING
BANDS. FLEXIBLE PIPE SHOULD BE STAKED ON EITHER SIDE.
3. A RIP RAP APRON SHALL BE PROVIDED AT THE OUTLET, IF
EMPTYING INTO A DISTURBED AREA.
STEEL
WIRE FENCING _
(IF APPLICABLE)
WOVEN FILTER FABRIC
-SEDIMENT PIT
NOT REQUIRED IF BASIN
IS LOCATED DOWNSTREAM
OF PIPE OUTLET.
4. THE SOIL AROUND AND UNDER THE INLET PIPE AND ENTRANCE
SECTION SHALL BE HAND TAMPED IN 4" LIFTS TO THE TOP OF
THE EARTH DIKE.
5. FOLLOW-UP INSPECTION AND ANY NEEDED MAINTENANCE SHALL
BE PERFORMED AFTER EACH STORM BY THE FINANCIALLY RESPONSIBLE
PARTY OR HIS AGENT.
6. OUTLET PIPE SHOULD BE TAKEN OVER OR THROUGH ANY SILT FENCE,
TAKING CARE NOT TO VOID THE EFFECTIVENESS OF THE SILT FENCE.
FLEXIBLE PIPE SLOPE DRAIN
N.T.S.
4' MAX.
WASHED STONE HARDWARE CLOTH
(NCDOT #5 OR BETWEEN POSTS AND
#57) `COVERED BY STONE
GENERAL NOTES:
1. SEDIMENT FILTER OUTLET AND HARDWARE CLOTH SHALL BE 16 INCHES HIGH BUT
NO TALLER THAN 18 INCHES.
2. HARDWARE CLOTH SHALL BE ANCHORED TO THE STEEL POSTS SECURELY USING
APPROPRIATE ANCHORS. HARDWARE CLOTH SHALL BE KEYED IN A MINIMUM OF
12 INCHES IN LENGTH AND BACKFILLED PROPERLY AS SHOWN IN ABOVE DETAIL.
3. POSTS SHALL BE NO MORE THAN 4 FEET APART.
4. SITE OUTLETS AT ANY POINT SMALL CONCENTRATED FLOWS ARE ANTICIPATED
AND AT THE DIRECTION OF THE INSPECTOR.
SILT FENCE OUTLET
N.T.S.
STEEL POST
HARDWARE CLOTH
WASHED STONE
(NCDOT #5 OR
#57)
FLOW
II ANCHOR SKIRT;
u EXCAVATE
TRENCH AND
COMPACT
MAINTENANCE NOTES: BACKFILL
1. FILTER OUTLETS SHALL BE INSPECTED BY THE FINANCIALLY RESPONSIBLE
PARTY OR HIS AGENT IMMEDIATELY AFTER EACH RAINFALL AND AT LEAST
DAILY DURING PROLONGED RAINFALL. ANY REPAIRS NEEDED SHALL BE MADE
IMMEDIATELY.
2. THE STONE SHALL BE REPLACED PROMPTLY AFTER ANY EVENT THAT HAS
CLOGGED OR REMOVED IT.
3. SEDIMENT DEPOSITS SHOULD BE REMOVED WHEN DEPOSITS REACH HALF
THE HEIGHT OF THE BARRIER. ANY SEDIMENT DEPOSITS REMAINING IN
PLACE AFTER THE SILT FENCE OUTLET IS REMOVED SHALL BE DRESSED TO
CONFORM TO THE EXISTING GRADE, PREPARED AND SEEDED.
* * * 3 Days Before Digging
North Carolina 811
811 or1-800-632-4949
Remote Ticket Entry
http://nc811.org/remoteticketentry.htm
'•
SSI
33046
4-12-19
� •G• P
STIPULATION FOR REUSE
THIS DRAWING WAS PREPARED FOR USE
ON A SPECIFIC SITE, SKYLAND DRIVE
TOWNHOMES, S. SKYLAND DRIVE, MT.
PLEASANT, INC, CONTEMPORANEOUSLY
WITH ITS ISSUE DATE ON 4/12/19. AND
IT IS NOT SUITABLE FOR USE ON A
DIFFERENT PROJECT SITE OR AT A LATER
TIME. USE OF THIS DRAWING FOR
REFERENCE OR EXAMPLE ON ANOTHER
PROJECT REQUIRES THE SERVICES OF
PROPERLY LICENSED ARCHITECTS AND
ENGINEERS. REPRODUCTION OF THIS
DRAWING FOR REUSE ON ANOTHER
PROJECT IS NOT AUTHORIZED AND MAY
BE CONTRARY TO THE LAW.
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MODIFICATION LOG
JOB NUMBER: C190010
CHECKED BY: BMF
DRAWN BY: BHE
DATE: 4-12-2019
[99£-0 # N&-4
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EROSION
CONTROL
DETAILS
EEC C794