20091085 Ver 2_More Info Received_20100203

Kimley-Horn
and Associates, Inc.
pr?c¢orr??
F- ER 3 2010
DENR - WATER QUALITY
WETLANDS AND STORMWATER BRANCH
February 2, 2010
Mr. Joe Gyamfi
2321 Crabtree Blvd
Raleigh, NC 27604
F.X.p DR- 1085 Ua
¦
suite 100
1919 South Boulevard
Charlotte, North Carolina
28203-4778
Subject: Troutman Towne Center - Troutman, NC
Comment Response Letter
Our Ref: 018426001
Dear Mr. Gyamfi:
We are writing in response to the engineering review comments for the subject
project. A list of the comments and our responses follows:
1. Wet Pond 1:
a. Short-circuiting of flows:
i. OPTION 1: Please look into the possibility of combining
the two forebays into a larger one and locate it at the
present location of smaller forebay. There appears to
be enough relief from 91-MH to the smaller forebay
to bring the flow to that location. This way, you will
have single forebay weir, have additional space and
volume, minimize grading and maintenance issues
with two forebays and berms and even
ii. OPTION 2: Please extend about three-quarters length of
the longer portion of the forebay weir to the
temporary pool elevation so as to elongate the flow
path from the eastern inlet to the outlet. Please
ensure the following requirements are maintained as
you extend the berm: 2:1 side slope, minimum 5ft
width at the top of the weir, and percentage of
forebay volume to overall pond volume should fall
within 18-22%.
OPTION 2 was used to avoid short-circuiting the flow of
wet detention pond 1. OPTION 1 was not used due to the
close proximity of geogrid to proposed relocation of
storm sewer pipe.
b. Please provide documentation to support the reported 10-
year storm elevation in the pond.
See attached Hydrocad Reports in calculation package.
¦
TEL [phone]
FAX [phone]
Mr. Joe Gyamfi, February 2, 2010, Page 2
? ? ? Kimley-Horn
and Associates, Inc.
c. This office recommends that the secondary spillways be
designed for the excess discharge (9.55cfs) from the next
available storm (i.e.25-year storm) since almost all the
routed flow from the 10-year storm outlets through the
primary control structure to the Level Spreader.
The primary outlet structure and pipe are now designed
to route the entire 10-year storm event. Since both ponds
are large enough to detain the 25-year storm event as
well, the emergency spillways are now designed using the
pre-development 25-year flow. Both spillway widths
increased.
d. One of the major design elements (#15) of a wet pond states
that "the BMP shall not be located to produce adverse
impacts on the water levels in adjacent wetlands". The BMP
Manual then states under Section 10.3.2 (Siting of BMP) that
the Permanent Pool Elevation (PPE) shall be located no
more than 6 inches above or below the Seasonal High Water
Table (SHWT). Two major issues with the wet pond 1
arising from the above statements are:
i. The BMP has been located very close to a
wetland.
ii. The Soil report indicates that the actual
groundwater table elevation ranges from 867 to
869 feet from bore holes (D1-D4) installed at the
location of the BMP. This implies that the SHWT
would, at a minimum, be 2 feet above the
permanent pool elevation of 867 feet.
Because of the issues stated above, please submit the following:
OPTION 1: Detailed engineering measures necessary to
prevent impacts to the wetland during the construction
stages of the BMP and also during its use as sediment
basin and subsequently as a wet pond. This should
include a narrative of the sequence of construction or
installation activities, necessary structures or devices
(both temporary and permanent) and supported plans or
diagrams that will be put in place. Section 10.3.8 or the
BMP Manual may be helpful.
OPTION 2: On the other hand, if you are convinced that
the location will not adversely affect the wetland, please
submit engineering calculations and hydro geological
analysis to demonstrate and/or support your assertion.
Please refer to Section 10.3.2 of the BMP Manual for
guidance.
Another possible solution would be to raise the bottom of the
pond and the permanent pool elevation if the required surface
? ? ? Kimley-Horn
and Associates, Inc.
Mr. Joe Gyamfi, February 2, 2010, Page 3
area can still be achieved, in addition t o providing a liner,
irrespective of whichever option you choose.
Clay liners are now proposed for each pond. A note was
added to the plans (C-26) stating: MINIMUM 12"
THICK COMPACTED CLAY LINER ALONG THE
INTERIOR OF ALL POND SLOPES FROM
PERMANENT POOL TO BOTTOM OF POND.
LINER MUST HAVE AN INFILTRATION RATE OF
NO MORE THAN 0.01 IN/HR. INFILTRATION RATE
SHALL BE TESTED BY THE CONSTRUCTION
TESTING LABORATORY AND VERIFIED BY THE
GEOTECHNICAL ENGINEER.
2. Level Spreader for Pond 1:
a. Please provide photos of the vegetation down slope of the
Level Spreader that is being used as the filter strip.
See attached.
b. Please re-orient your outlet control structure and discharge
pipe such that the incoming flow from the pond shall be
discharged at an angle to the "blind swale" of the Level
Spreader. This was discussed in detail with Ms. Beverly
Rosenbloom on January 20, 2010.
The level spreader is now 65' and is angled from the
point of pond outlet discharge more than 90°. This angle
is as big as it can be based on the new length and
proximity to the existing wetlands.
c. Please submit a completed Operation and Maintenance
Agreement for the Level Spreader-Filter Strip System.
The signed form is forthcoming from Walmart.
3. Wet Pond 2:
a. The drawdown time of the water quality volume is
approximately 4.7 days and not 2.6 days as reported on the
supplement form.
The revised drawdown time is shown on the supplement
form.
b. Since there was no borings at this location, and no
information of the seasonal high water table, please add liner
to this pond.
? ? Kimley-Horn
and Associates, Inc.
Mr. Joe Gyamfl, February 2, 2010, Page 4
A liner was added to this pond as well with a similar note
as above (see response to comment 1d).
4. Wet Ponds 1 and 2:
a. The temporary pool volume under Section H (Design
Information) of the Supplement Form should be the storage
volume provided between the primary orifice and the next
available opening (orifice, weir) on the control structure.
The reported storage volume is now revised.
b. Please ensure that the provided storage volume described in
(a) above equals or exceeds the required minimum water
quality treatment volume. In addition, please make sure they
correctly match the values reported in the stage-area-storage
table.
The stage-area-storage table was not calculating the
storage volume correctly. An additional calculation was
added and the correct volume is now reported.
We trust this meets your needs for continued review of this project, but please
feel free to call me at [phone] with any questions or concerns.
Sincerely yours,
KIMLEY-HORN AND ASSOCIATES, INC.
Beverly Rosenbloom, El
Enclosure
cc: Tim Dollander, Troutman Towne Center, LLC
Brian Fletcher, Troutman Towne Center, LLC
(K\CSE_LDEV\013426 Chivas Retail Partners\000 Troutman Towne Center\Conespondence\L020210.DWQ-CONEvfNT-RESPONSE.BRR.doc)
Permit No.
(to be provided by DWQ)
OF w A rE9
ARA O? PG
?n
WDENR
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
401 CERTIFICATION APPLICATION FORM
WET DETENTION BASIN SUPPLEMENT
This form must be filled out, printed and submitted.
The Required Items Checklist (Part 111) must be printed, filled out and submitted along with all of the required information.
I. PROJECT INFORMATION
Project name Troutman Towne Center
Contact person Beverly Rosenbloom
Phone number 704.319-7699
Date 2/2/2010
Drainage area number Wet Detention Pond 1 (DA-1)
11. DESIGN INFORMATION
Site Characteristics
Drainage area 646,430 ftz
Impervious area, post-development 549,727 ft2
% impervious 85.04%
Design rainfall depth 1.0 in
Storage Volume: Non-SA Waters
Minimum volume required
Volume provided
Storage Volume: SA Waters
1.5" runoff volume
Pre-development 1-yr, 24-hr runoff
Post-development 1-yr, 24-hr runoff
Minimum volume required
Volume provided
Peak Flow Calculations
Is the pre/post control of the lyr 24hr storm peak flow required?
1-yr, 24-hr rainfall depth
Rational C, pre-development
Rational C, post-development
Rainfall intensity: 1-yr, 24-hr storm
Pre-development 1-yr, 24-hr peak flow
Post-development 1-yr, 24-hr peak flow
Pre/Post 1-yr, 24-hr peak flow control
Elevations
Temporary pool elevation
Permanent pool elevation
SHWT elevation (approx. at the perm. pool elevation)
Top of 1 Oft vegetated shelf elevation
Bottom of 10ft vegetated shelf elevation
Sediment cleanout, top elevation (bottom of pond)
Sediment cleanout, bottom elevation
Sediment storage provided
Is there additional volume stored above the state-required temp. pool?
Elevation of the top of the additional volume
43,923 ft3 OK
92,620 ft3
OK, volume provided is equal to or in excess of volume required.
ft3
ft3
ft3
ft3
ft3
(Y or N)
2.8 in
0.30 (unitless)
0.68 (unitless)
0.12 in/hr OK
0.44 ft3/sec
51.66 ft3/sec
51.22 ft3/sec
870.00 fmsl
867.00 fmsl
fmsl
867.50 fmsl
866.50 fmsl Data not needed for calculation option #1, but OK if provided.
860.00 fmsl
859.00 fmsl Data not needed for calculation option #1, but OK if provided.
1.00 ft
(Y or N)
870.0 fmsl OK
Form SW401-Wet Detention Basin-Rev.8-9/17/09 Parts I. & II. Design Summary, Page 1 of 2
Permit No
(to be provided by DWQ)
!l. DESIGN INFORMATION
Surface Areas
Area, temporary pool 35,544 ft2
Area REQUIRED, permanent pool 23,207 ft2
SA/DA ratio 3.59 (unitless)
Area PROVIDED, permanent pool, Apenpwl 24,268 ft2 OK
Area, bottom of 1 Oft vegetated shelf, Abrn shell 15,059 ft2
Area, sediment cleanout, top elevation (bottom of pond), Abo,jo„d 3,549 ft2
Volumes
Volume, temporary pool
Volume, permanent pool, Vpen pool
Volume, forebay (sum of forebays if more than one forebay)
Forebay % of permanent pool volume
SA/DA Table Data
Design TSS removal
Coastal SA/DA Table Used?
Mountain/Piedmont SA/DA Table Used?
SA/DA ratio
Average depth (used in SA/DA table):
Calculation option 1 used? (See Figure 10-2b)
Volume, permanent pool, Vp pool
Area provided, permanent pool, A,._poo,
Average depth calculated
Average depth used in SA/DA, d, (Round to nearest 0.5ft)
Calculation option 2 used? (See Figure 10-2b)
Area provided, permanent pool, Ape r,-P l
Area, bottom of 1 Oft vegetated shelf, Abm shed
Area, sediment cleanout, top elevation (bottom of pond), Abate
"Depth" (distance b/w bottom of 1 Oft shelf and top of sediment)
Average depth calculated
Average depth used in SA/DA, day, (Round to nearest 0.5ft)
Drawdown Calculations
Drawdown through orifice?
Diameter of orifice (if circular)
Area of orifice (if-non-circular)
Coefficient of discharge (CD)
Driving head (Ho)
Drawdown through weir?
Weir type
Coefficient of discharge (Cw)
Length of weir (L)
Driving head (H)
Pre-development 1-yr, 24-hr peak flow
Post-development 1-yr, 24-hr peak flow
Storage volume discharge rate (through discharge orifice or weir)
Storage volume drawdown time
Additional Information
Vegetated side slopes
Vegetated shelf slope
Vegetated shelf width
Length of flowpath to width ratio
Length to width ratio
Trash rack for overflow & orifice?
Freeboard provided
Vegetated fitter provided?
Recorded drainage easement provided?
Capures all runoff at ultimate build-out?
Drain mechanism for maintenance or emergencies is:
Form SW401-Wet Detention Basin-Rev.8-9/17/09
92,620 ft3 OK
83,923 ft3
17,072 ft3
20.3% % OK
85%
N (Y or N)
Y (Y or N)
3.59 (unitless)
Y (Y or N)
83,923 ft3
24,268 ft2
3.46 ft OK
3.0 ft Insufficient. Check calculation.
N (Y or N)
24,268 ft2
15,059 ft2
3,549 ft2
6.50 ft
ft
ft
Y (Y or N)
2.90 in
in2
0.60 (unitless)
0.97 ft
(Y or N)
(unitless)
(unitless)
ft
ft
0.44 ft3/sec
51.66 ft3/sec
0.21 ft3/sec
4.80 days OK, draws down in 2-5 days.
3 :1 OK
10 :1 OK
10.0 ft OK
3 :1 OK
3.6 :1 OK
Y (Y or N) OK
1.0 ft OK
Y (Y or N) OK
Y (Y or N) OK
Y (Y or N) OK
Emergency Pipe
Parts I. & II. Design Summary, Page 2 of 2
Permit No.
(to be provided by DWQ)
III. REQUIRED ITEMS CHECKLIST
Please indicate the page or plan sheet numbers where the supporting documentation can be found. An incomplete submittal package will
result in a request for additional information. This will delay final review and approval of the project. Initial in the space provided to
indicate the following design requirements have been met. If the applicant has designated an agent, the agent may initial below. If a
requirement has not been met, attach justification.
Page/ Plan
Initials Sheet No.
BRR _C-14 1. Plans (1" - 50' or larger) of the entire site showing:
Design at ultimate build-out,
Off-site drainage (if applicable),
Delineated drainage basins (include Rational C coefficient per basin),
Basin dimensions,
Pretreatment system,
High flow bypass system,
Maintenance access,
Proposed drainage easement and public right of way (ROW),
Overflow device, and
Boundaries of drainage easement.
BRR C-25-C-27 2. Partial plan (1" = 30' or larger) and details for the wet detention basin showing:
Outlet structure with trash rack or similar,
Maintenance access,
Permanent pool dimensions,
Forebay and main pond with hardened emergency spillway,
Basin cross-section,
Vegetation specification for planting shelf, and
Filter strip.
BRR C-25-C-27 3. Section view of the wet detention basin (1" = 20' or larger) showing:
Side slopes, 3:1 or lower,
Pretreatment and treatment areas, and
Inlet and outlet structures.
BRR C-5-C-8 4. If the basin is used for sediment and erosion control during construction, clean out of the basin is specified
on the plans prior to use as a wet detention basin.
BRR attached 5. A table of elevations, areas, incremental volumes & accumulated volumes for overall pond and for forebay,
to verify volume provided.
BRR C-5-C-8 6. A construction sequence that shows how the wet detention basin will be protected from sediment until the
entire drainage area is stabilized.
BRR attached 7. The supporting calculations.
BRR attached 8. A copy of the signed and notarized operation and maintenance (0&M) agreement.
9. A copy of the deed restrictions (if required).
BRR attached 10. A soils report that is based upon an actual field investigation, soil borings, and infiltration tests. County
soil maps are not an acceptable source of soils information.
Form SW401-Wet Detention Basin-Rev.8-9/17/09 Part III. Required Items Checklist, Page 1 of 1
Permit
mAt")h
NCDENR
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
401 CERTIFICATION APPLICATION FORM
WET DETENTION BASIN SUPPLEMENT
This form must be filled out, printed and submitted.
The Required Items Checklist (Part 111) must be printed, filled out and submitted along with all of the required information.
(to be provided by DWQ)
W A rf9O
?{ y
OL °M? wor^? -<
I. PROJECT INFORMATION
Project name Troutman Towne Center
Contact person Beverly Rosenbloom
Phone number 704-319-7699
Date 2/2/2010
Drainage area number Wet Detention Pond 1 (DA-1)
II. DESIGN INFORMATION
Site Characteristics
Drainage area 646,430 ft2
Impervious area, post-development 549,727 ft2
% impervious 85.04%
Design rainfall depth 1.0 in
Storage Volume: Non-SA Waters
Minimum volume required
Volume provided
Storage Volume: SA Waters
1.5" runoff volume
Pre-development 1-yr, 24-hr runoff
Post-development 1-yr, 24-hr runoff
Minimum volume required
Volume provided
Peak Flow Calculations
Is the pre/post control of the 1 yr 24hr storm peak flow required?
1-yr, 24-hr rainfall depth
Rational C, pre-development
Rational C, post-development
Rainfall intensity: 1-yr, 24-hr storm
Pre-development 1-yr, 24-hr peak flow
Post-development 1-yr, 24-hr peak flow
Pre/Post 1-yr, 24-hr peak flow control
Elevations
Temporary pool elevation
Permanent pool elevation
SHWT elevation (approx. at the perm. pool elevation)
Top of 1 Off vegetated shelf elevation
Bottom of 1 Oft vegetated shelf elevation
Sediment cleanout, top elevation (bottom of pond)
Sediment cleanout, bottom elevation
Sediment storage provided
Is there additional volume stored above the state-required temp. pool?
Elevation of the top of the additional volume
43,923 ft3 OK
92,620 ft3
OK, volume provided is equal to or in excess of volume required.
ft3
ft3
ft3
ft3
ft3
Y (Y or N)
2.8 in
0.30 (unitless)
0.68 (unitless)
0.12 inthr OK
0.44 ft3/sec
51.66 ft3/sec
51.22 ft3/sec
870.00 fmsl
867.00 fmsl
fmsl
867.50 fmsl
866.50 fmsl Data not needed for calculation option #1, but OK if provided.
860.00 fmsl
859.00 fmsl Data not needed for calculation option #1, but OK lf provided.
1.00 ft
Y (Y or N)
870.0 fmsl OK
Form SW401-Wet Detention Basin-Rev.8-9/17/09 Parts I. & II. Design Summary, Page 1 of 2
Permit No
(to be provided by DWQ)
II. DESIGN INFORMATION
Surface Areas
Area, temporary pool 35,544 ft2
Area REQUIRED, permanent pool 23,207 ft2
SA/DA ratio 3.59 (unitless)
Area PROVIDED, permanent pool, Apean_p., 24,268 ft2 OK
Area, bottom of 1 Oft vegetated shelf, Aw shetl 15,059 ft
Area, sediment cleanout, top elevation (bottom of pond), Abo,_,m 3,549 ft2
Volumes
Volume, temporary pool 92,620 ft3 OK
Volume, permanent pool, Vper,-pwi 83,923 ft3
Volume, forebay (sum of forebays if more than one forebay) 17,072 ft3
Forebay % of permanent pool volume 20.3% % OK
SA/DA Table Data
Design TSS removal 85%
Coastal SA/DA Table Used? N (Y or N)
Mountain/Piedmont SAIDA Table Used? Y (Y or N)
SA/DA ratio 3.59 (unftless)
Average depth (used in SA/DA table):
Calculation option 1 used? (See Figure 10-2b) Y (Y or N)
Volume, permanent pool, Vperm-pwl 83,923 ft3
Area provided, permanent pool, Apevn_oo 24,268 ft
Average depth calculated 3.46 ft OK
Average depth used in SAIDA, day, (Round to nearest 0.5ft) 3.0 It Insufficient. Check calculation.
Calculation option 2 used? (See Figure 10-2b) N (Y or N)
Area provided, permanent pool, ApQnwi 24,268 ft2
Area, bottom of 1 Oft vegetated shelf, Abcsnee 15,059 ft2
Area, sediment cleanout, top elevation (bottom of pond), Aye, 3,549 ft2
"Depth" (distance b/w bottom of 10ft shelf and top of sediment) 6.50 ft
Average depth calculated It
Average depth used in SA/DA, day, (Round to nearest 0.5ft) ft
Drawdown Calculations
Drawdown through orifice? Y (Y or N)
Diameter of orifice (if circular) 2.90 in
Area of orifice ('rf-non-circular) in2
Coefficient of discharge (CD) 0.60 (unftless)
Driving head (Ho) 0.97 It
Drawdown through weir? (Y or N)
Weir type (unitless)
Coefficient of discharge (CW) (unftless)
Length of weir (L) ft
Driving head (H) ft
Pre-development 1-yr, 24-hr peak flow 0.44 ft3/sec
Post-development 1-yr, 24-hr peak flow 51.66 ft3/sec
Storage volume discharge rate (through discharge orifice or weir) 0.21 ft3/sec
Storage volume drawdown time 4.80 days OK, draws down in 2-5 days.
Additional Information
Vegetated side slopes 3 :1 OK
Vegetated shelf slope 10 :1 OK
Vegetated shelf width 10.0 ft OK
Length of flowpath to width ratio 3 :1 OK
Length to width ratio 3.6 :1 OK
Trash rack for overflow & orifice? Y (Y or N) OK
Freeboard provided 1.0 ft OK
Vegetated filter provided? Y (Y or N) OK
Recorded drainage easement provided? Y (Y or N) OK
Capures all runoff at ultimate build-out? Y (Y or N) OK
Drain mechanism for maintenance or emergencies is: Emergency Pipe
Form SW401-Wet Detention Basin-Rev.8-9/17/09 Parts I. & It. Design Summary, Page 2 of 2
Permit No.
(to be provided by DWQ)
III. REQUIRED ITEMS CHECKLIST
Please indicate the page or plan sheet numbers where the supporting documentation can be found. An incomplete submittal package will
result in a request for additional information. This will delay final review and approval of the project. Initial in the space provided to
indicate the following design requirements have been met. If the applicant has designated an agent, the agent may initial below. If a
requirement has not been met, attach justification.
Page/ Plan
Initials Sheet No.
BRR _C-14 1. Plans (1" 50' or larger) of the entire site showing:
Design at ultimate build-out,
Off-site drainage (if applicable),
Delineated drainage basins (include Rational C coefficient per basin),
Basin dimensions,
Pretreatment system,
High flow bypass system,
Maintenance access,
Proposed drainage easement and public right of way (ROW),
Overflow device, and
Boundaries of drainage easement.
BRR C-25-C-27 2. Partial plan (1" = 30' or larger) and details for the wet detention basin showing:
Outlet structure with trash rack or similar,
Maintenance access,
Permanent pool dimensions,
Forebay and main pond with hardened emergency spillway,
Basin cross-section,
Vegetation specification for planting shelf, and
Filter strip.
BRR C-25-C-27 3. Section view of the wet detention basin (1" = 20' or larger) showing:
Side slopes, 3:1 or lower,
Pretreatment and treatment areas, and
Inlet and outlet structures.
BRR C-5-C-8 4. If the basin is used for sediment and erosion control during construction, clean out of the basin is specified
on the plans prior to use as a wet detention basin.
BRR attached 5. A table of elevations, areas, incremental volumes & accumulated volumes for overall pond and for forebay,
to verify volume provided.
BRR C-5-C-8 6. A construction sequence that shows how the wet detention basin will be protected from sediment until the
entire drainage area is stabilized.
BRR attached 7. The supporting calculations
BRR attached 8. A copy of the signed and notarized operation and maintenance (0&M) agreement.
9. A copy of the deed restrictions (if required).
BRR attached 10. A soils report that is based upon an actual field investigation, soil borings, and infiltration tests. County
soil maps are not an acceptable source of soils information.
Form SW401-Wet Detention Basin-Rev.8-9/17/09 Part III. Required Items Checklist, Page 1 of 1
Permit
A`
NCDENR
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
401 CERTIFICATION APPLICATION FORM
WET DETENTION BASIN SUPPLEMENT
This form must be filled out, printed and submitted.
The Required Items Checklist (Part 111) must be printed, filled out and submitted along with all of the required information.
(to be provided by DWQ)
W A 7- Rp
.rr,w
I. PROJECT INFORMATION
Project name Troutman Towne Center
Contact person Beverly Rosenbloom
Phone number 704-319.7699
Date
Drainage area number
Wet Detention Pond 2 (DA-2 and DA-3)
II. DESIGN INFORMATION
Site Characteristics
Drainage area
Impervious area, post-development
% impervious
Design rainfall depth
Storage Volume: Non-SA Waters
Minimum volume required
Volume provided
Storage Volume: SA Waters
1.5" runoff volume
Pre-development 1-yr, 24-hr runoff
Post-development 1-yr, 24-hr runoff
Minimum volume required
Volume provided
Peak Flow Calculations
Is the pre/post control of the 1 yr 24hr storm peak flow required?
1-yr, 24-hr rainfall depth
Rational C, pre-development
Rational C, post-development
Rainfall intensity: 1-yr, 24-hr storm
Pre-development 1-yr, 24-hr peak flow
Post-development 1-yr, 24-hr peak flow
Pre/Post 1-yr, 24-hr peak flow control
Elevations
Temporary pool elevation
Permanent pool elevation
SHWT elevation (approx. at the perm. pool elevation)
Top of 10ft vegetated shelf elevation
Bottom of 1 Oft vegetated shelf elevation
Sediment cleanout, top elevation (bottom of pond)
Sediment cleanout, bottom elevation
Sediment storage provided
Is there additional volume stored above the state-required temp. pool?
Elevation of the top of the additional volume
2/2/2010
1,588,633 ft2
1,041,955 ft2
65.59%
1.0 in
84,766 ft3 OK
90,738 ft3
OK, volume provided is equal to or in excess of volume required.
ft3
ft3
ft3
ft3
ft3
Y (Y or N)
2.8 in
0.30 (unitless)
0.68 (unitless)
0.12 in/hr OK
6.04 ft3/sec
87.20 ft3/sec
81.16 ft3/sec
873.40 fmsl
872.00 fmsl
fmsl
872.50 fmsl
871.50 fmsl Data not needed for calculation option #1, but OK 9 provided.
867.00 fmsl
866.00 fmsl Data not needed for calculation option #1, but OK 9 provided.
1.00 ft
Y (Y or N)
873.4 fmsl OK
Form SW401-Wet Detention Basin-Rev.8-9/17/09 Parts I. & II. Design Summary, Page 1 of 2
Permit No
(to be provided by DWQ)
11. DESIGN INFORMATION
Surface Areas
Area, temporary pool 67,856 ft2
Area REQUIRED, permanent pool 57,985 ff
SAIDA ratio 3.65 (unitless)
Area PROVIDED, permanent pool, Apen" 59,041 ft2 OK
Area, bottom of 1 Oft vegetated shelf, Ate, shell 39,718 ft2
Area, sediment cleanout, top elevation (bottom of pond), Abot nd 26,439 ft
Volumes
Volume, temporary pool
Volume, permanent pool, VPermyouol
Volume, forebay (sum of forebays if more than one forebay)
Forebay % of permanent pool volume
SA/DA Table Data
Design TSS removal
Coastal SAIDA Table Used?
Mountain/Piedmont SAIDA Table Used?
SA/DA ratio
Average depth (used in SAIDA table):
Calculation option 1 used? (See Figure 10-2b)
Volume, permanent pool, Vpen-1=1
Area provided, permanent pool, Apen-pool
Average depth calculated
Average depth used in SAIDA, d,,, (Round to nearest 0.5ft)
Calculation option 2 used? (See Figure 10-2b)
Area provided, permanent pool, Apenpw,
Area, bottom of 1 Oft vegetated shelf, Aw_s,ea
Area, sediment cleanout, top elevation (bottom of pond), Ab,,_po d
"Depth" (distance b/w bottom of 1 Oft shelf and top of sediment)
Average depth calculated
Average depth used in SAIDA, d,v, (Round to nearest 0.5ft)
Drawdown Calculations
Drawdown through orifice?
Diameter of orifice (if circular)
Area of orif ice (if-non-circular)
Coefficient of discharge (Co)
Driving head (Ho)
Drawdown through weir?
Weir type
Coefficient of discharge (C„,)
Length of weir (L)
Driving head (H)
Pre-development 1-yr, 24-hr peak flow
Post-development 1-yr, 24-hr peak flow
Storage volume discharge rate (through discharge orifice or weir)
Storage volume drawdown time
Additional Information
Vegetated side slopes
Vegetated shelf slope
Vegetated shelf width
Length of flowpath to width ratio
Length to width ratio
Trash rack for overflow & orifice?
Freeboard provided
Vegetated filter provided?
Recorded drainage easement provided?
Capures all runoff at ultimate build-out?
Drain mechanism for maintenance or emergencies is:
Form SW401-Wet Detention Basin-Rev.8-9/17/09
90,738 ft3 OK
215,126 ft3
45,564 ft3
21.2% % OK
90%
N (Y or N)
Y (Y or N)
3.65 (unltless)
Y (Y or N)
215,126 ft3
59,041 ft2
3.64 It OK
3.5 ft OK
N (Y or N)
59,041 ft2
39,718 ft
26,439 ft2
4.50 ft
3.64 ft OK
3.5 ft OK
Y (Y or N)
5.00 in
in2
0.60 (unftless)
0.41 If
(Y or N)
(unitless)
(unitless)
It
ft
6.04 ft3/sec
87.20 ft3/sec
0.41 ft3/sec
2.50 days OK, draws down in 2-5 days.
3 :1 OK
10 :1 OK
10.0 ft OK
3 :1 OK
4.0 :1 OK
Y (Y or N) OK
1.0 ft OK
N (Y or N) OK
Y (Y or N) OK
Y (Y or N) OK
Emergency pipe
Parts I. & II. Design Summary, Page 2 of 2
Permit
(to be provided by DWQ)
III. REQUIRED ITEMS CHECKLIST
Please indicate the page or plan sheet numbers where the supporting documentation can be found. An incomplete submittal package will
result in a request for additional information. This will delay final review and approval of the project. Initial in the space provided to
indicate the following design requirements have been met. If the applicant has designated an agent, the agent may initial below. If a
requirement has not been met, attach justification.
Page/ Plan
Initials Sheet No.
BRR _C-14 1. Plans (1" 50' or larger) of the entire site showing:
Design at ultimate build-out,
Off-site drainage (if applicable),
Delineated drainage basins (include Rational C coefficient per basin),
Basin dimensions,
Pretreatment system,
High flow bypass system,
Maintenance access,
Proposed drainage easement and public right of way (ROW),
Overflow device, and
Boundaries of drainage easement.
BRR C-25-C-27 2. Partial plan (1" = 30' or larger) and details for the wet detention basin showing:
Outlet structure with trash rack or similar,
Maintenance access,
Permanent pool dimensions,
Forebay and main pond with hardened emergency spillway,
Basin cross-section,
Vegetation specification for planting shelf, and
Filter strip.
BRR C-25-C-27 3. Section view of the wet detention basin (1" = 20' or larger) showing:
Side slopes, 3:1 or lower,
Pretreatment and treatment areas, and
Inlet and outlet structures.
BRR C-5-C-8 4. If the basin is used for sediment and erosion control during construction, clean out of the basin is specified
on the plans prior to use as a wet detention basin.
BRR attached 5. A table of elevations, areas, incremental volumes & accumulated volumes for overall pond and for forebay,
to verify volume provided.
BRR C-5-C-8 6. A construction sequence that shows how the wet detention basin will be protected from sediment until the
entire drainage area is stabilized.
BRR attached 7. The supporting calculations.
BRR attached 8. A copy of the signed and notarized operation and maintenance (0&M) agreement.
9. A copy of the deed restrictions (if required).
BRR attached 10. A soils report that is based upon an actual field investigation, soil borings, and infiltration tests. County
soil maps are not an acceptable source of soils information.
Form SW401-Wet Detention Basin-Rev.8-9/17/09 Part III. Required Items Checklist, Page 1 of 1
Permit
A*`AF
NCDENR
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
401 CERTIFICATION APPLICATION FORM
WET DETENTION BASIN SUPPLEMENT
This form must be filled out, printed and submitted.
The Required Items Checklist (Part 111) must be printed, filled out and submitted along with all of the required information.
(to be provided by DWQ)
W A?TFROG
C, ? ?
I. PROJECT INFORMATION
Project name Troutman Towne Center
Contact person Beverly Rosenbloom
Phone number 704-319-7699
Date 2/2/2010
Drainage area number Wet Detention Pond 2 (DA-2 and DA-3)
II. DESIGN INFORMATION
Site Characteristics
Drainage area 1,588,633 ft2
Impervious area, post-development 1,041,955 ft2
% impervious 65.59%
Design rainfall depth 1.0 in
Storage Volume: Non-SA Waters
Minimum volume required 84,766 ft3 OK
Volume provided 90,738 ft3
OK, volume provided is equal to or in excess of volume required.
Storage Volume: SA Waters
1.5" runoff volume
Pre-development 1-yr, 24-hr runoff
Post-development 1-yr, 24-hr runoff
Minimum volume required
Volume provided
Peak Flow Calculations
Is the pre/post control of the 1 yr 24hr storm peak flow required?
1-yr, 24-hr rainfall depth
Rational C, pre-development
Rational C, post-development
Rainfall intensity: 1-yr, 24-hr storm
Pre-development 1-yr, 24-hr peak flow
Post-development 1-yr, 24-hr peak flow
Pre/Post 1-yr, 24-hr peak flow control
Elevations
Temporary pool elevation
Permanent pool elevation
SHWT elevation (approx. at the perm. pool elevation)
Top of 10ft vegetated shelf elevation
Bottom of 10ft vegetated shelf elevation
Sediment cleanout, top elevation (bottom of pond)
Sediment cleanout, bottom elevation
Sediment storage provided
Is there additional volume stored above the state-required temp. pool?
Elevation of the top of the additional volume
ft3
ft3
ft3
ft3
ft3
Y (Y or N)
2.8 in
0.30 (unitless)
0.68 (unitless)
0.12 in/hr OK
6.04 ft3/sec
87.20 ft3/sec
81.16 ft3/sec
873.40 fmsl
872.00 fmsl
fmsl
872.50 fmsl
871.50 fmsl Data not needed for calculation option #1, but OK if provided.
867.00 fmsl
866.00 fmsl Data not needed for calculation option #1, but OK if provided.
1.00 ft
Y (Y or N)
873.4 fmsl OK
Form SW401-Wet Detention Basin-Rev.8-9/17/09 Parts I. & II. Design Summary, Page 1 of 2
Permit No.
(to be provided by DWQ)
IL DESIGN INFORMATION
Surface Areas
Area, temporary pool 67,856 ft2
Area REQUIRED, permanent pool 57,985 ft2
SA/DA ratio 3.65 (unitless)
Area PROVIDED, permanent pool, Apenyoo, 59,041 ft2 OK
Area, bottom of 1 Oft vegetated shelf, Aw She 39,718 ft2
Area, sediment cleanout, top elevation (bottom of pond), AbIlmd 26,439 ft2
Volumes
Volume, temporary pool 90,738 ft3 OK
Volume, permanent pool, Vpevn poo 215,126 ft3
Volume, forebay (sum of forebays if more than one forebay) 45,564 ft3
Forebay % of permanent pool volume 21.2% % OK
SA/DA Table Data
Design TSS removal 90%
Coastal SAIDA Table Used? N (Y or N)
Mountain/Piedmont SA/DA Table Used? Y (Y or N)
SA/DA ratio 3.65 (unitless)
Average depth (used in SAIDA table):
Calculation option 1 used? (See Figure 10-2b) Y (Y or N)
Volume, permanent pool, Vpermyoo, 215,126 ft3
Area provided, permanent pool, Apenvoo, 59,041 ft2
Average depth calculated 3.64 ft OK
Average depth used in SA/DA, deV, (Round to nearest 0.5ft) 3.5 ft OK
Calculation option 2 used? (See Figure 10-2b) N (Y or N)
Area provided, permanent pool, Ape.-Poo, 59,041 f'
Area, bottom of 1 Oft vegetated shelf, Abm_aher 39,718 fiz
Area, sediment cleanout, top elevation (bottom of pond), Abot ow 26,439 ft2
"Depth" (distance b/w bottom of 1 Oft shelf and top of sediment) 4.50 ft
Average depth calculated 3.64 ft OK
Average depth used in SAIDA, deV, (Round to nearest 0.5ft) 3.5 ft OK
Drawdown Calculations
Drawdown through orifice? Y (Y or N)
Diameter of orifice (if circular) 5.00 in
Area of orifice (if-non-circular) in2
Coefficient of discharge (CD) 0.60 (unitless)
Driving head (Ho) 0.41 ft
Drawdown through weir? (Y or N)
Weir type (unitless)
Coefficient of discharge (C„,) (unitless)
Length of weir (L) ft
Driving head (H) ft
Pre-development 1-yr, 24-hr peak flow 6.04 ft3/sec
Post-development 1-yr, 24-hr peak flow 87.20 ft3/sec
Storage volume discharge rate (through discharge orifice or weir) 0.41 ft3/sec
Storage volume drawdown time 2.50 days OK, draws down in 2-5 days.
Additional Information
Vegetated side slopes 3 :1 OK
Vegetated shelf slope 10 :1 OK
Vegetated shelf width 10.0 ft OK
Length of flowpath to width ratio 3 :1 OK
Length to width ratio 4.0 :1 OK
Trash rack for overflow & orifice? Y (Y or N) OK
Freeboard provided 1.0 ft OK
Vegetated fitter provided? N (Y or N) OK
Recorded drainage easement provided? Y (Y or N) OK
Capures all runoff at ultimate build-out? Y (Y or N) OK
Drain mechanism for maintenance or emergencies is: Emergency pipe
Form SW401-Wet Detention Basin-Rev.8-9/17/09 Parts I. & It. Design Summary, Page 2 of 2
Permit No
(to be provided by DWQ)
Jill. REQUIRED ITEMS CHECKLIST
Please indicate the page or plan sheet numbers where the supporting documentation can be found. An incomplete submittal package will
result in a request for additional information. This will delay final review and approval of the project. Initial in the space provided to
indicate the following design requirements have been met. If the applicant has designated an agent, the agent may initial below. If a
requirement has not been met, attach justification.
Page/ Plan
Initials Sheet No.
BRR _C-14 1. Plans (1" 50' or larger) of the entire site showing:
Design at ultimate build-out,
Off-site drainage (if applicable),
Delineated drainage basins (include Rational C coefficient per basin),
Basin dimensions,
Pretreatment system,
High flow bypass system,
Maintenance access,
Proposed drainage easement and public right of way (ROW),
Overflow device, and
Boundaries of drainage easement.
BRR C-25-C-27 2. Partial plan (1" = 30' or larger) and details for the wet detention basin showing:
Outlet structure with trash rack or similar,
Maintenance access,
Permanent pool dimensions,
Forebay and main pond with hardened emergency spillway,
Basin cross-section,
Vegetation specification for planting shelf, and
Filter strip.
BRR C-25-C-27 3. Section view of the wet detention basin (1" = 20' or larger) showing:
Side slopes, 3:1 or lower,
Pretreatment and treatment areas, and
Inlet and outlet structures.
BRR C-5-C-8 4. If the basin is used for sediment and erosion control during construction, clean out of the basin is specified
on the plans prior to use as a wet detention basin.
BRR attached 5. A table of elevations, areas, incremental volumes & accumulated volumes for overall pond and for forebay,
to verify volume provided.
BRR C-5-C-8 6. A construction sequence that shows how the wet detention basin will be protected from sediment until the
entire drainage area is stabilized.
BRR attached 7. The supporting calculations.
BRR attached 8. A copy of the signed and notarized operation and maintenance (0&M) agreement.
9. A copy of the deed restrictions (if required).
BRR attached 10. A soils report that is based upon an actual field investigation, soil borings, and infiltration tests. County
soil maps are not an acceptable source of soils information.
Form SW401-Wet Detention Basin-Rev.8-9/17/09 Part III. Required Items Checklist, Page 1 of 1
1
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Stormwater Management Calculations
Troutman Towne Center
Construction Documents

FEB "S 2U,
Prepared for:
DM. VanR cwnurr
North Point Resources, LLC wVw"mPVOR1,'*,17Eftw*"
124 Iron Gate Circle
Mooresville, NC 28117
© Kimley-Horn and Associates, Inc. 2010
Kimley-Horn
and Associates, Inc.
This document, together with the concepts and designs presented herein, as an instrument of service, is intended only for the specific
purpose and client for which it was prepared. Reuse of and improper reliance on this document without written authorization and
adaptation by Kimley-Horn and Associates, Inc. shall be without liability to Kimley-Horn and Associates, Inc.
TROUTMAN TOWNE CENTER
CONSTRUCTION DOCUMENTS
TROUTMAN, NORTH CAROLINA
STORMWATER MANAGEMENT
CALCULATIONS
Prepared for:
North Point Resources, LLC
124 Iron Gate Circle
Mooresville, NC 28117
Prepared by:
Kimley-Horn and Associates, Inc.
1919 South Boulevard, Suite 100
Charlotte, North Carolina 28203
C A
vp?':oF?SS10 f?2 ?•
14
'``J???' 1 t? i 1111y? \\\2• t
2 D
February 2010
KHA Ref: 018426001
TABLE OF CONTENTS
i OVERVIEW
SITE MAPS
- SITE VICINITY MAP
- USDA SOIL CLASSIFICATION MAP
FLOOD INSURANCE RATE MAP USGS QUADRANGLE
- WATERSHED MAPS
PRE-DEVELOPMENT WATERSHED MAP
• POST-DEVELOPMENT WATERSHED MAP
WATER QUALITY
WET POND CALCULATIONS
- VOLUME AND SURFACE AREA CALCULATIONS
ANTI-FLOTATION CALCULATIONS
- RIP RAP CALCULATIONS
WATER QUANTITY
CURVE NUMBER CALCULATIONS
- TIME OF CONCENTRATION CALCULATIONS
HYDROCAD HYDROLOGY REPORTS
- WET DETENTION POND I
WET DETENTION POND 2
- STORMWATER MANAGEMENT CALCULATIONS i
- Troutman Towne Center, Troutman, North Carolina
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OVERVIEW
STORMWA TER MANAGEMENT & EROSION CONTROL CALCULATIONS
Troutman Towne Center, Troutman, North Carolina

Background
OVERVIEW
This report contains the approach and results of a stormwater and erosion control analysis
conducted for the Troutman Towne Center commercial development. The 60-acre project site is
located in the south west quadrant of the interchange of Interstate 77 and US-21 in the Town of
Troutman.
The existing on-site conditions consist primarily of woods and dense brush. Approximately 4.8
acres adjacent to US-21 consist of gravel and there is currently a paved access path to an existing
cell tower. This tower will remain on site. The Wilco Hess gas station and Wendy's restaurant
just north of the site drain onto the site therefore these areas are accounted for in the stormwater
and erosion control calculations.
The site topography varies from elevation 930 ft to elevation 840 ft. Ken Branch stream
separates the site flowing from Interstate 85 to US-21. An existing culvert under I-85 drains
approximately 62 acres to this existing stream. The stream carries a total of 147 acres from the
site and across Interstate 85 into two existing box culverts under US-21.
Floodplain/Floodway
The proposed site does not lie within a 100-year floodway boundary as determined by FIRM
Map# 3710474000J, Panel 4740 (see Figure).
Water Quality
Water quality treatment by means of permanent Best Management Practices (BMP's) will be
provided using two wet detention basins as treatment. The ponds are designed to treat the first
inch of runoff per the North Carolina Division of Water Quality (NCDWQ) Stormwater Best
Management Practices Manual and will draw down over a period of two to five days. Wet
Detention Basin 2 is designed to provide a minimum 90% average annual removal of Total
Suspended Solids (TSS). Wet Detention Basin 1 is designed to provide a minimum of 85%
average annual removal of TSS and therefore discharges to a filter strip and level spreader.
Water Quantity
The proposed wet detention basins have been designed to address the water quantity
requirements to match pre- and post-development peak runoff rates for the 1-year, 24-hour storm
events per the NCDWQ BMP Manual. These ponds will also control the peak runoff rates for the
10-year, 24-hour storm event per the Town of Troutman Unified Development Ordinance (UDO).
The 25-year, 24-hour storm event was checked for 6" of freeboard at the top of bank.
STORMWA TER MANAGEMENT CALCULATIONS
Troutman Towne Center, Troutman, North Carolina
Results
Pre-Dev Flow Post-Dev Flow Pre-Dev Flow Post-Dev Flow
(1-yr, 24-hr storm, (1-yr, 24-hr storm, (10-yr, 24-hr storm, (10-yr. 24-hr storm,
CFS CFS CFS CFS
Wet Pond
1 0.44 0.43 11.70 5.12
Wet Pond
2 6.04 2.38 32.66 27.37
Erosion Control
The project will require disturbance of approximately 60 acres. Proposed temporary erosion
control measures include stone construction entrances, silt fence, tree protection fence, diversion
ditches, sediment traps and sediment basins. Wet Detention Basin 1 will also be utilized as a
riser basin during the construction of the project. Permanent erosion control measures include
seeding, riprap aprons, and a lining of the proposed ditches. All measures have been designed in
accordance with North Carolina Department of Environment and Natural Resources (NCDENR)
Erosion and Sediment Control Planning and Design Manual.
Conclusion
The proposed wet detention basins were designed using methods prescribed by the
aforementioned resources. HydroCAD software was utilized to evaluate the pre-development
and post-development flow rates. HydroCAD utilizes TR-55 methods of calculating times of
concentration (based on sheet, shallow concentrated, and channelized flows) and SCS curve
number method of generating hydrographs (results are provided in Appendix C). Based on the
analyses provided herein, the proposed system will be adequate to address the stormwater
requirements of NCDWQ and the Town of Troutman.
STORMWA TER MANAGEMENT CALCULATIONS
Troutman Towne Center, Troutman, North Carolina
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SITE MAPS
STORMWA TER MANAGEMENT & EROSION CONTROL CALCULATIONS
Troutman Towne Center, Troutman, North Carolina
T UTMAN
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CENTER
Kimley-Horn and Associates, inc. OUTMAN, NC NTS 1
THIS DOCUMENT. TOGETHER WTN THE CONCEPTS AND DESIGNS PRESENTED T MMK AS AN INSTRUMENT OF SERVICE, IS Nflp1DED ONLY FOR THE PURPOSE AND CLIENT FOR WOCH IT WAS PREPARED. REUSE
OF AND NPROPER RELIANCE ON THIS DOCUMENT LNTHOUT WTITIEN AUDMZATION AND ADAPTATION BY KMEY-HORN AND ASSOCIATES. INC. SHALL RE WTHOUT UANUTY TO KNIEY-HORN AND ASSWATES, INC.
- K,\CSE-LDEV\018426 Chivas RetaR Partners\000 Troutman Towne Center\Calcs\Storm\Solls aril VlcWt Ma .dw
I
TROUTMAN TOWNE
CENTER SOILS MAP FIGURE
-
Kimley-Horn and Associates, Inc. TROUTMAN, NC NTS 2
TIMS DOOAAENT. WOEIHER NTH THE CONCEPTS AND DESIONS PRESENTED HEREIK AS AN INSTRUMENT OF SERWM IS NTENDED ONLY FOR THE PURPOSE AND CLENT FOR MHICH IT WAS PREPARED. REUSE
OF AND IMPROPER RELIANCE ON THIS DOCUMENT NTHOUT WRITTEN AUTNMZATION AND ADAPTATION BY 0AEY-HORN AND ASSOCIATES. MJC. SHALL BE NTHOUT UARUTY TO K*A.EY-HORN AND ASSOCIATES. WC.
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PRE-DEVELOPMENT
DRAINAGE AREA MAP
STORMWA TER MANAGEMENT & EROSION CONTROL CALCULATIONS
Troutman Towne Center, Troutman, North Carolina

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POST-DEVELOPMENT
DRAINAGE AREA MAP
STORMWA TER MANAGEMENT & EROSION CONTROL CALCULATIONS
Troutman Towne Center, Troutman, North Carolina
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WET POND CALCULATIONS
STORMWATER MANAGEMENT & EROSION CONTROL CALCULATIONS
Troutman Towne Center, Troutman, North Carolina
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pP-Z " Kimley-Horn
and Associates, Inc.
Project Information
WET DETENTION BASIN 1
Project Name: Troutman Towne Center
KHA Project #: 018426000
Designed by: BRR Date: 7/7/2009
Revised by: BRR Date: 8/30/2009
Revised by: Date:
Site Information
Sub Area Location: Drainage Area 1
Drainage Area (DA) = 14.84 Acres
Impervious Area (IA) = 12.62 Acres
Percent Impervious (1) = 85.0 %
Required Surface Area
Permanent Pool Depth: 3.00 ft
SA/DA = 3.59 (85% TSS Removal via Pond)
Min Req'd Surface Area = 23207 sf (at Permanent Pool)
Required Storage Volume:
Design Storm = 1 inch (Project Does Not Drain to SA waters)
Determine Rv Value = 0.05 +.009 (1) = 0.82 in/in
Storage Volume Required = 43,923 cf (above Permanent Pool)
Elevations
Bank Elevation = 873.00 ft
Top of Pond Elevation = 873.00 ft
Temporary Pool Elevation = 870.00 ft
Forebay Weir = 867.00 ft
Shelf Beginning Elevation = 867.50 ft
Permanent Pool Elevation = 867.00 ft
Shelf Ending Elevation = 866.50 ft
Bottom Elevation = 859.00 ft
Wet Basin Areas/Volumes
Area @ Top of Temporary Pool = 35,544 sf
Area @ Top of Permanent Pool = 24,268 sf
Volume of Temporary Storage = 89,718 cf
Side Slopes of Pond = 3 :1
Side Slopes of Shelf = 10 :1
Side Slopes of Pond (below shelf) = 3 :1
Is Permanent Pool Surface Area Sufficient (yes/no)?
Volume of Storage Provided 89,718 cf
Total Volume Sufficient (yes/no)? Yes
Orifice Size = 2.90 inches
Drawdown Time = 4.80 days
Area (s.f.)
35,544
24,268
(Elevation = 870.00)
(Elevation = 867.00)
Yes ( 24268 > 23207 ) sf
i
i
WET DETENTION BASIN 1
Project Information
Project Name: Troutman Towne Center
KHA Project #: 018426000
Designed by: BRR Date: 8/30/2009
Revised by: Date:
Revised by: Date:
Site Information
Sub Area Location
Drainage Area (DA) =
Impervious Area (IA) =
Percent Impervious (1) =
Orifice Sizing
Drainage Area 1
14.8 Acres
12.6 Acres
85.0 % (Drainage Area)
Q2 Days = 0.5192 cfs
Q5 Days - 0.2077 cfs
Orifice Size = 2.90 in
Q Orifice = 0.216 cfs
Drawdown Time = 4.80 days
less than 5 days (yes/no) ? Yes
greater than 2 days (yes/no) ? Yes
Orifice Equation: Q=CAgd(2gh)
(Flowrate required for a 2 day drawdown)
(Flowrate required for a 5 day drawdown)
(Diameter)
Q2< Q < Q5
c = 0.6
Ay= Area of Pipe = n/4D2
g = gravity = 32.2 ft/s2
h = orifice head = 1 /3 (TPE-PPE-1 /2D)
TPE = Temporary Pool Elevation
PPE = Permanent Pool Elevation
D = Diameter

Kirnley-Horn
C and Associates, Inc.
WET DETENTION BASIN 2
Project Information
Project Name: Troutman Towne Center
KHA Project #: 018426000
Designed by: BRR Date: 7/7/2009
Revised by: BRR Date: 9/1/2009
Revised by: Date:
Site Information
Sub Area Location: Drainage Area 3
Drainage Area (DA) = 36.47 Acres
Impervious Area (IA) = 23.92 Acres
Percent Impervious (1) = 65.6 %
Required Surface Area
Permanent Pool Depth: 3.25 ft
SA/DA = 3.65 (90% TSS Removal via Pond)
Min Req'd Surface Area = 57985 sf (at Permanent Pool)
Required Storage Volume:
Design Storm = 1 inch (Project Does Not Drain to SA waters)
Determine Rv Value = 0.05 +.009 (1) = 0.64 in/in
Storage Volume Required = 84766 cf (above Permanent Pool)
Elevations Area (s.f.)
Bank Elevation = 876.50 ft
Top of Pond Elevation = 876.50 ft
Temporary Pool Elevation = 873.40 ft 67,856
Forebay Weir = 872.00 ft
Shelf Beginning Elevation = 872.50 ft
Permanent Pool Elevation = 872.00 ft 59,041
Shelf Ending Elevation = 871.50 ft
Bottom Elevation = 864.00 ft
Wet Basin Areas/Volumes
Area @ Top of Temporary Pool =
Area @ Top of Permanent Pool =
Volume of Temporary Storage =
Side Slopes of Pond =
Side Slopes of Shelf =
Side Slopes of Pond (below shelf) =
Is Permanent Pool Surface Area Suffic
Volume of Storage Provided
67856 sf (Elevation = 873.40)
59041 sf (Elevation = 872.00 )
88828 cf
31
101
31
ient (yes/no)? Yes ( 59041 > 57985 ) sf
88828 cf
Total Volume Sufficient (yes/no)? Yes
Orifice Size = 5.00 inches
Drawdown Time = 2.5 days

WET DETENTION BASIN 2
Project Information
Project Name: Troutman Towne Center
KHA Project #: 018426000
Designed by: BRR Date:
Revised by: BRR Date:
Revised by: Date:
Site Information
Sub Area Location
Drainage Area (DA) =
Impervious Area (IA) =
Percent Impervious (1) =
Orifice Sizing
8/30/2009
9/1/2009
Drainage Area 3
36.5 Acres
23.9 Acres
65.6 % (Drainage Area)
Q2 Days = 0.5141 cfs
Q5 Days = 0.2056 cfs
Orifice Size = 5.00 in
Q Orifice = 0.414 cfs
Drawdown Time = 2.5 days
less than 5 days (yes/no) ? Yes
greater than 2 days (yes/no) ? Yes
Orifice Equation: Q=cAgV(2gh)
(Flowrate required for a 2 day drawdown)
(Flowrate required for a 5 day drawdown)
(Diameter)
Q2< Q < Q5
c = 0.6
A9= Area of Pipe = rt/4D2
g = gravity = 32.2 ft1s2
h = orifice head = 1/3 (TPE-PPE-1/2D)
TPE = Temporary Pool Elevation
PPE = Permanent Pool Elevation
D = Diameter

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VOLUME AND SURFACE AREA
CALCULATIONS
STORMWA TER MANAGEMENT & EROSION CONTROL CALCULATIONS
Troutman Towne Center, Troutman, North Carolina
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ANTI-FLOTATION CALCULATIONS
STORMWA TER MANAGEMENT & EROSION CONTROL CALCULATIONS
Troutman Towne Center, Troutman, North Carolina

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RIP RAP CALCULATIONS
STORMWA TER MANAGEMENT & EROSION CONTROL CALCULATIONS
Troutman Towne Center, Troutman, North Carolina

Troutman Towne Center Kimle -Horn and Associates, Inc.
Charlotte, North Carolina Date: 10/6/2009
KHA Project #: 018426001 Prepared by: KRT
Checked by:
RIP RAP APRON CALCULATIONS
Per NCDENR Design Manual
Structure:
Pipe Diameter (in):
Slope (%):
Manning (n):
Radius (in):
Pipe Area (sf):
Flowing Full:
10-year flow from ICPR:
Discharge (Q10) =
Pipe Diameter (in) =
d50 =
Design Conditions =
Width at Pipe Outlet'Do' (ft) _
Length of Apron 'La' (ft) =
Width at End of Apron 'W' (ft) _
Min. Stone Depth (in) _
Stone Class =
24
1.30 0.0130
0.011
12
3.14
Wetted
Perimeter Flow Area Hydraulic Flow Velocity
Depth Theta (ft) (sf) Radius Flow (GPD) (CFS) (fps)
24.0 6.283 6.283 3.142 0.500 19,754,345 30.57 9.73
14.21 3.512 3.512 1.937 0.552 13,003,378 20.12 10.39
20.12
24
0.5 Figure 8.06a
Assume Minimum Tailwater
6
13 Figure 8.06a
19
13.5
Class B
CURVE NUMBER CALCULATIONS
STORMWA TER MANAGEMENT & EROSION CONTROL CALCULATIONS
Troutman Towne Center, Troutman, North Carolina

- t Kiml
-H
rn
/
ey
o
and Iociates. Inc.

-Project Information

- Project Name: Troutman Towne Center
KHA Project #: 018426000
- Designed by: BRR
Revised by: BRR
- Revised by: BRR
Revised by: BRR

Pre vs. Post Runoff Analysis
Composite Curve Number (CN)
Date: 6/30/2009
Date: 9/112009
Date: 10/9/2009
Date: 12/2/2009
omposlte
Drainage Area Drainage Cover/Soil Hydrologic Soil Product of Curve Number
Name Location Name (Type) Cover Description' Group Curve # (CN)" Area (ac) CN x area (CN)
RE-DEVELOPMENT
J Appling, Cecil, Woods
DA-1 OUTFALL 1 Lloyd, Madison Good Condition B 55 9.00 495 55
al-Mart (Lot Appling, Cecil, Brush
#11) Lloyd, Madison >75% Ground Cover B 48 6.22 299 48
Appling, Cecil, Brush
Lloyd, Madison <50% Ground Cover B 67 1.84 123 67
17.06 917 53.7
Appling, Cecil, Woods
DA-2 OUTFALL 1 Lloyd, Madison Good Condition B 55 1.78 98 55
Hotel Appling, Cecil, Brush
o)
( Lloyd, Madison >75% Ground Cover B 48 0.64 31 48
L Appling, Cecil,
Lloyd, Madison Existing Impervious Pavement B 98 0.61 60 98
3.03 188 62.2
Appling, Cecil, Woods
DA-3 OUTFALL 1 Lloyd, Madison Good Condition B 55 0.32 17 55
Outparcels and Appling, Cecil, Brush
Wilco Lloyd, Madison >75% Ground Cover B 48 17.02 817 48
Appling, Cecil,
Lloyd, Madison Existing Open Space B 61 0.88 53 61
Appling, Cecil,
Lloyd, Madison Existing Impervious Pavement B 98 9.62 943 98
27.84 1831 65.8
J ; Jotal Pre-Development Drainage Area to Detention Pond 2 (DA-2 and DA-3):J 30.87 2019 65.4
K:\CSE_LDEV\018426 Chivas Retail Partners\000 Troutman Towne Center\Calcs\Storm\2009-12-02_Stormwater Calculations.xls 1 of 2

• p-.! Kimley-Horn
r \
h! and Associates, Inc.

-Project Information
Project Name: Troutman Towne Center
KHA Project #: 018426000
- Designed by: BRR
Revised by: BRR
- Revised by: BRR
Revised by: BRR
Pre vs. Post Runoff Analysis
Composite Curve Number (CN)
Date: 6/30/2009
Date: 9/11/2009
Date: 10/9/2009
Date: 12/2/2009
•
composite
Drainage Area Drainage Cover/Soil Hydrologic Soil Product of Curve Number
Name Location Name (Type) Cover Description' Group Curve # (CN)" Area (ac) CN x area (CN)
POST DEVELOPMENT
Appling, Cecil,
DA-1 POND 1 Lloyd, Madison Impervious B 98 12.62 1237 98
Wal-Mart (Lot Appling, Cecil,
#11) Lloyd, Madison Open Space B 61 2.22 135 61
{ 14.84 1372.18 92.46
Appling, Cecil, Brush
UND DA-1 OUTFALL 1 Lloyd, Madison >75% Ground Cover B 48 0.96 46 48
Appling, Cecil,
Lloyd, Madison Open Space B 61 1.06 65 61
2.02 110.74 54.82
Appling, Cecil, Brush
DA-2 POND 2 Lloyd, Madison >75% Ground Cover B 48 018 9 48
Hotel Appling, Cecil,
(Lot #10) Lloyd, Madison Impervious B 98 2.61 256 98
Appling, Cecil,
Lloyd, Madison Open Space B 61 0.29 18 61
{ 3.08 282.05 91.61
Appling, Cecil,
DA-3 POND 2 Lloyd, Madison Impervious B 98 21.31 2088 98
Wilco and Appling, Cecil, Woods
Outparcels Lloyd, Madison Good Condition B 55 0.08 4 55
Appling, Cecil, Brush
Lloyd, Madison >75% Ground Cover B 48 5.15 247 48
Appling, Cecil,
Lloyd, Madison Open Space B 61 6.86 418 61
33.40 2758.20 82.59
Total Post-Devel opment Drainage Area to Detention Pond 2 (DA-2 and DA-3): 36.47 3040 83.4
Appling, Cecil, Brush
UND DA-3 OUTFALL 2 Lloyd, Madison >75% Ground Cover B 48 0.57 27 48
Appling, Cecil,
Lloyd, Madison Open Space B 61 0.49 30 61
{ 1.06 57.25 54.01
-` Cover Descriptions per North Carolina Division of Water Quality Stormwater Best Manavement Practices Manual, Table 3-5
-" From North Carolina Division of Water Quality Stormwater Best Manavement Practices Manual, Table 3-5
Outparcels = Lot's #3,4,5,7,8,9 and Drive B, C and Lexus Drive
•
- K:\CSETLDEV\018426 Chivas Retail Partners\000 Troutman Towne Center\Calcs\Storm\2009-12-02_Stormwater Calculations. As
2of2
TIME OF CONCENTRATION CALCULATIONS
STORMWA TER MANAGEMENT & EROSION CONTROL CALCULATIONS
Troutman Towne Center, Troutman, North Carolina
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HYDROCAD HYDROLOGY REPORTS
1-YEAR, 10-YEAR, 25-YEAR EVENTS
WET DETENTION POND 1
STORMWATER MANAGEMENT & EROSION CONTROL CALCULATIONS
Troutman Towne Center, Troutman, North Carolina
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1S
Pre-development
3S
Undetained
Post-development
zs
Post-development
77
4P
Wet Deten ion Pond 1
Z 5P
Outfall 1
Subca F ach on Link
2010-01-21_Wal-Mart Pond Type 11 24-hr 1 year, 24-hour Rainfall=2.85"
Prepared by Kimley-Horn and Associates, Inc. Printed 2/2/2010
HydroCADO 9.00 s/n 05123 @2009 HydroCAD Software Solutions LLC Paae 2
Time span=0.00-20.00 hrs, dt=0.05 hrs, 401 points
Runoff by SCS TR-20 method, UH=SCS
Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method
Subcatchment 1S: Pre-development Runoff Area=17.060 ac 0.00% Impervious Runoff Depth>0.10"
Tc=27.3 min CN=54 Runoff=0.44 cfs 0.148 of
Subcatchment 2S: Post-development Runoff Area=14.840 ac 0.00% Impervious Runoff Depth>1.89"
Tc=5.0 min CN=92 Runoff=51.66 cfs 2.337 of
Subcatchment 3S: Undetained Post-development Runoff Area=2.020 ac 0.00% Impervious Runoff Depth>0.12"
Tc=5.0 min CN=55 Runoff=0.14 cfs 0.021 of
Pond 4P: Wet Detention Pond 1 Peak Elev=869.95' Storage=90,416 cf Inflow=51.66 cfs 2.337 of
Primary=0.37 cfs 0.261 of Secondary=0.00 cfs 0.000 of Outflow=0.37 cfs 0.261 of
Pond 5P: Outfall 1
Inflow=0.43 cfs 0.282 of
Primary=0.43 cfs 0.282 of
Total Runoff Area = 33.920 ac Runoff Volume = 2.506 of Average Runoff Depth = 0.89"
100.00% Pervious= 33.920 ac 0.00% Impervious = 0.000 ac
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• 2010-01-21 Wal-Mart Pond Type 1124-hr 1 year, 24-hour Rainfall=2.85"
Prepared by Kimley-Horn and Associates, Inc. Printed 2/2/2010
• HydroCAD® 9.00 s/n 05123 @2009 HydroCAD Software Solutions LLC Page 3
• Summary for Subcatchment 1S: Pre-development
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• Runoff = 0.44 cfs @ 12.61 hrs, Volume= 0.148 af, Depth> 0.10"
• Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-20.00 hrs, dt= 0.05 hrs
., Type II 24-hr 1 year, 24-hour Rainfall=2.85"
• Area (ac) CN Description
• 17.060 54
17.060 100.00% Pervious Area
• Tc Length Slope Velocity Capacity Description
• (min) (feet) (ft/ft) (ft/sec) (cfs)
27.3 Direct Entry, see spreadsheet
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• Subcatchment IS: Pre-development
• Hydrograph
• 0.44 cfs ¦ Runoff
0.45 Type III24-hr 1 year...
• 0.4 24-hour
• 0.35 Rainfall=2.85"
• 0.3 Runoff
Area 17.060 ac
0.25 Runoff Volume=0148 of
• U. Runoff De ..
LL pth>0.10
• 0.2
Tc=27.3 min
• 0.15 CN=54
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2010-01-21_Wal-Mart Pond Type 11 24-hr 1 year, 24-hour Rainfall=2.85"
Prepared by Kimley-Horn and Associates, Inc. Printed 2/2/2010
HydroCADO 9.00 s/n 05123 @2009 HydroCAD Software Solutions LLC Page 4
Summary for Subcatchment 2S: Post-development
Runoff = 51.66 cfs @ 11.95 hrs, Volume= 2.337 af, Depth> 1.89"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 1 year, 24-hour Rainfall=2.85"
Area (ac) CN Description
14.840 92
14.840 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry,
Subcatchment 2S: Post-development
Hydrograph
¦ Runoff
51.66 cfs
50 Type II 24-hr 1 year
45 24-hour
40 Rainfall=2.85"
35 Runoff Area=14.840 ac
30 Runoff Volume=2.337 of
LL 25 Runoff Depth>1.89"
20 Tc=5.0 min
15 CN=92
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0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Time (hours)
2010-01-21 Wal-Mart Pond Type 11 24-hr 1 year, 24-hour Rainfall=2.85"
Prepared by Kimley-Horn and Associates, Inc. Printed 2/2/2010
HydroCAD® 9.00 s/n 05123 @2009 Hydr2CAD Software Solutions LLC Page 5
Summary for Subcatchment 3S: Undetained Post-development
Runoff = 0.14 cfs @ 12.03 hrs, Volume= 0.021 af, Depth> 0.12"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 1 year, 24-hour Rainfall=2.85"
Area (ac) CN Description
' 2.020 55
2.020 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry,
Subcatchment 3S: Undetained Post-development
Hydrograph
0.15
0.14
0.13:
Type II 24-hr 1 year
0.12- 24-hour
°" Rainfall=2.85"
01 Runoff Area=2.020 ac
0.09-.
0.08
Runoff Volume=0.021 of
0.07
U
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Runoff Depth>0.12"
0.06 Tc=5.0 min
0.05-
0.04 .

CN=55'
0.03
0.02
0.01 .
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Time (hours)
2010-01-21 Wal-Mart Pond Type 11 24-hr 1 year, 24-hour Rainfall=2.85"
Prepared by Kimley-Horn and Associates, Inc. Printed 2/2/2010
HydroCAD® 9.00 s/n 05123 © 2009 HydroCAD Software Solutions LLC Page 6
Summary for Pond 4P: Wet Detention Pond 1
Inflow Area = 14.840 ac, 0.00% Impervious, Inflow Depth > 1.89" for 1 year, 24-hour event
Inflow = 51.66 cfs @ 11.95 hrs, Volume= 2.337 of
Outflow = 0.37 cfs @ 20.00 hrs, Volume= 0.261 af, Atten= 99%, Lag= 482.8 min
Primary = 0.37 cfs @ 20.00 hrs, Volume= 0.261 of
Secondary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of
Routing by Stor-Ind method, Time Span= 0.00-20.00 hrs, dt= 0.05 hrs
Peak Elev= 869.95'@ 20.00 hrs Surf.Area= 35,406 sf Storage= 90,416 cf
Plug-Flow detention time= 347.8 min calculated for 0.260 of (11% of inflow)
Center-of-Mass det. time= 174.4 min ( 936.4 - 762.0 )
Volume Invert Avail.Storage Storage Description
#1 867.00' 212,289 cf Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic-feet) (cubic-feet)
867.00 24,268 0 0
868.00 29,605 26,937 26,937
869.00 32,538 31,072 58,008
870.00 35,544 34,041 92,049
871.00 38,750 37,147 129,196
872.00 41,532 40,141 169,337
873.00 44,371 42,952 212,289
Device Routing Invert Outlet Devices
#1 Primary 866.00' 24.0" Round Culvert L= 50.4' RCP, groove end projecting, Ke= 0.200
Outlet Invert= 864.00' S= 0.03977' Cc= 0.900
n= 0.011 Concrete pipe, straight & clean
#2 Device 1 867.00' 2.9" Vert. Water Quality Orifice C= 0.600
#3 Device 1 870.00' 12.0" W x 6.0" H Vert. Water Quantity Control Weir C=0.600
#4 Device 1 871.60' 14.0' long x 0.5' breadth Open Grate on Control Structure
Head (feet) 0.20 0.40 0.60 0.80 1.00
Coef. (English) 2.80 2.92 3.08 3.30 3.32
#5 Secondary 872.00' 25.0' long x 30.0' breadth Emergency Spillway
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Coef. (English) 2.68 2.70 2.70 2.64 2.63 2.64 2.64 2.63
Primary OutFlow Max=0.37 cfs @ 20.00 hrs HW=869.95' (Free Discharge)
L1=Culvert (Passes 0.37 cfs of 32.50 cfs potential flow)
2=Water Quality Orifice (Orifice Controls 0.37 cfs @ 8.10 fps)
3=Water Quantity Control Weir ( Controls 0.00 cfs)
=Open Grate on Control Structure ( Controls 0.00 cfs)
Secondary OutFlow Max=0.00 cfs @ 0.00 hrs HW=867.00' (Free Discharge)
L5=Emergency Spillway ( Controls 0.00 cfs)
2010-01-21_Wal-Mart Pond Type 11 24-hr 1 year, 24-hour Rainfall=2.85"
Prepared by Kimley-Horn and Associates, Inc. Printed 2/2/2010
HydroCAD® 9.00 s/n 05123 © 2009 HydroCAD Software Solutions LLC Page 7
Pond 4P: Wet Detention Pond 1
Hydrograph
¦ Inflow
51.66 cfs ha outflow
Inflow Area=14.840 ac ¦ Primary
(.] Secondary
55 Peak Elev=869.95'
50
Storage=90,416 cf
45-
40-
35-.
- -
30
3
o
FL 25-
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20-
15
1
10
0.37 cfs
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Time (hours)
2010-01-21 -Wal-Mart Pond Type 11 24-hr 1 year, 24-hour Rainfall=2.85"
Prepared by Kimley-Horn and Associates, Inc. Printed 2/2/2010
HydroCAD® 9.00 s/n 05123 © 2009 HydroCAD Software Solutions LLC Page 8
Stage-Discharge for Pond 4P: Wet Detention Pond 1
Elevation Discharge Primary Secondary
(feet) (cfs) (cfs) (cfs)
867.00 0.00 0.00 0.00
867.10 0.02 0.02 0.00
867.20 0.06 0.06 0.00
867.30 0.09 0.09 0.00
867.40 0.12 0.12 0.00
867.50 0.14 0.14 0.00
867.60 0.15 0.15 0.00
867.70 0.17 0.17 0.00
867.80 0.18 0.18 0.00
867.90 0.19 0.19 0.00
868.00 0.21 0.21 0.00
868.10 0.22 0.22 0.00
868.20 0.23 0.23 0.00
868.30 0.24 0.24 0.00
868.40 0.25 0.25 0.00
868.50 0.26 0.26 0.00
868.60 0.27 0.27 0.00
868.70 0.28 0.28 0.00
868.80 0.29 0.29 0.00
868.90 0.29 0.29 0.00
869.00 0.30 0.30 0.00
869.10 0.31 0.31 0.00
869.20 0.32 0.32 0.00
869.30 0.33 0.33 0.00
869.40 0.33 0.33 0.00
869.50 0.34 0.34 0.00
869.60 0.35 0.35 0.00
869.70 0.35 0.35 0.00
869.80 0.36 0.36 0.00
869.90 0.37 0.37 0.00
870.00 0.37 0.37 0.00
870.10 0.48 0.48 0.00
870.20 0.67 0.67 0.00
870.30 0.92 0.92 0.00
870.40 1.21 1.21 0.00
870.50 1.54 1.54 0.00
870.60 1.80 1.80 0.00
870.70 2.01 2.01 0.00
870.80 2.19 2.19 0.00
870.90 2.36 2.36 0.00
871.00 2.51 2.51 0.00
871.10 2.65 2.65 0.00
871.20 2.79 2.79 0.00
871.30 2.91 2.91 0.00
871.40 3.03 3.03 0.00
871.50 3.15 3.15 0.00
871.60 3.26 3.26 0.00
871.70 4.61 4.61 0.00
871.80 6.98 6.98 0.00
871.90 10.15 10.15 0.00
872.00 14.01 14.01 0.00
872.10 20.73 18.61 2.12
872.20 29.89 23.90 5.99
872.30 41.15 30.10 11.05
Elevation Discharge Primary Secondary
(feet) (cfs) (cfs) (cfs)
872.40 54.17 37.09 17.08
872.50 67.55 43.69 23.86
872.60 76.12 44.75 31.37
872.70 84.24 45.14 39.09
872.80 92.76 45.54 47.23
872.90 102.17 45.93 56.25
873.00 112.07 46.32 65.75
2010-01-21_Wal-Mart Pond Type 11 24-hr 1 year, 24-hour Rainfall=2.85"
Prepared by Kimley-Horn and Associates, Inc. Printed 2/2/2010
HydroCAD® 9.00 s/n 05123 © 2009 HydroCAD Software Solutions LLC Page 9
Summary for Pond 5P: Outfall 1
Inflow Area = 16.860 ac, 0.00% Impervious, Inflow Depth > 0.20" for 1 year, 24-hour event
Inflow = 0.43 cfs @ 12.04 hrs, Volume= 0.282 of
Primary = 0.43 cfs @ 12.04 hrs, Volume= 0.282 af, Atten= 0%, Lag= 0.0 min
Routing by Stor-Ind method, Time Span= 0.00-20.00 hrs, dt= 0.05 hrs
Pond 5P: Outfall 1
Hydrograph -ill
¦ Inflow
¦ Primary
w
U
3
O
LL
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Time (hours)
i
2010-01-21 Wal-Mart Pond Type 11 24-hr 10 year, 24-hour Rainfall=5.10"
Prepared by Kimley-Horn and Associates, Inc. Printed 2/2/2010
HydroCADO 9.00 s/n 05123 @2009 HydroCAD Software Solutions LLC Page 1
Time span=0.00-20.00 hrs, dt=0.05 hrs, 401 points
Runoff by SCS TR-20 method, UH=SCS
Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method
Subcatchment 1S: Pre-development Runoff Area=17.060 ac 0.00% Impervious Runoff Depth>0.84"
Tc=27.3 min CN=54 Runoff=11.70 cfs 1.192 of
Subcatchment 2S: Post-development Runoff Area=14.840 ac 0.00% Impervious Runoff Depth>3.94"
Tc=5.0 min CN=92 Runoff=102.26 cfs 4.878 of
Subcatchment 3S: Undetained Post-developmentRunoff Area=2.020 ac 0.00% Impervious Runoff Depth>0.91"
Tc=5.0 min CN=55 Runoff=3.42 cfs 0.153 of
Pond 4P: Wet Detention Pond 1 Peak Elev=871.57' Storage=151,580 cf Inflow=102.26 cfs 4.878 of
Primary=3.22 cfs 2.003 of Secondary=0.00 cfs 0.000 of Outflow=3.22 cfs 2.003 of
Pond 5P: Outfall 1
Inflow=5.12 cfs 2.155 of
Primary=5.12 cfs 2.155 of
Total Runoff Area = 33.920 ac Runoff Volume = 6.222 of Average Runoff Depth = 2.20"
100.00% Pervious= 33.920 ac 0.00% Impervious = 0.000 ac
2010-01-21_Wal-Mart Pond Type l/ 24-hr 10 year, 24-hour Rainfall=5.10"
Prepared by Kimley-Horn and Associates, Inc. Printed 2/2/2010
HydroCAD® 9.00 s/n 05123 @2009 HydroCAD Software Solutions LLC Page 2
Summary for Subcatchment 1S: Pre-development
Runoff = 11.70 cfs @ 12.26 hrs, Volume= 1.192 af, Depth> 0.84"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 10 year, 24-hour Rainfall=5.10"
Area (ac) CN Description
17.060 54
17.060 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
27.3 Direct Entry, see spreadsheet
Summary for Subcatchment 2S: Post-development
Runoff = 102.26 cfs @ 11.95 hrs, Volume= 4.878 af, Depth> 3.94"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 10 year, 24-hour Rainfall=5.10"
Area (ac) CN Description
14.840 92
14.840 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry,
Summary for Subcatchment 3S: Undetained Post-development
Runoff = 3.42 cfs @ 11.98 hrs, Volume= 0.153 af, Depth> 0.91"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 10 year, 24-hour Rainfall=5.10"
Area (ac) CN Description
2.020 55
2.020 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry,
2010-01-21 Wal-Mart Pond Type 11 24-hr 10 year, 24-hour Rainfall=5.10"
Prepared by Kimley-Horn and Associates, Inc. Printed 2/2/2010
HydroCAD® 9.00 s/n 05123 @2009 HydroCAD Software Solutions LLC Page 3
Summary for Pond 4P: Wet Detention Pond 1
Inflow Area = 14.840 ac, 0.00% Impervious, Inflow Depth > 3.94" for 10 year, 24-hour event
Inflow = 102.26 cfs @ 11.95 hrs, Volume= 4.878 of
Outflow = 3.22 cfs @ 13.74 hrs, Volume= 2.003 af, Atten= 97%, Lag= 107.6 min
Primary = 3.22 cfs @ 13.74 hrs, Volume= 2.003 of
Secondary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of
Routing by Stor-Ind method, Time Span= 0.00-20.00 hrs, dt= 0.05 hrs
Peak Elev= 871.57'@ 13.74 hrs Surf.Area= 40,325 sf Storage= 151,580 cf
Plug-Flow detention time= 290.6 min calculated for 1.998 of (41% of inflow)
Center-of-Mass det. time= 194.0 min ( 938.5 - 744.5 )
Volume Invert Avail.Storage Storage Description
- '
#1 867.00 212,289 cf Custom Stage Data (Prismatic) Listed below (Recalc)

- Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic-feet) (cubic-feet)
867.00 24,268 0 0
- 868.00 29,605 26,937 26,937
869.00 32,538 31,072 58,008
870.00 35,544 34,041 92,049
. 871.00 38,750 37,147 129,196
872.00 41,532 40,141 169,337
873.00 44,371 42,952 212,289
Device Routing Invert Outlet Devices
#1 Primary 866.00' 24.0" Round Culvert L= 50.4' RCP, groove end projecting, Ke= 0.200
Outlet Invert= 864.00' S= 0.03977' Cc= 0.900
n= 0.011 Concrete pipe, straight & clean
#2 Device 1 867.00' 2.9" Vert. Water Quality Orifice C= 0.600
#3 Device 1 870.00' 12.0" W x 6.0" H Vert. Water Quantity Control Weir C=0.600
#4 Device 1 871.60' 14.0' long x ON breadth Open Grate on Control Structure
Head (feet) 0.20 0.40 0.60 0.80 1.00
Coef. (English) 2.80 2.92 3.08 3.30 3.32
#5 Secondary 872.00' 25.0' long x 30.0' breadth Emergency Spillway
- Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
_ Coef. (English) 2.68 2.70 2.70 2.64 2.63 2.64 2.64 2.63
Primary OutFlow Max=3.22 cfs @ 13.74 hrs HW=871.57' (Free Discharge)
L1=Culvert (Passes 3.22 cfs of 40.40 cfs potential flow)
2=Water Quality Orifice (Orifice Controls 0.47 cfs @ 10.15 fps)
3=Water Quantity Control Weir (Orifice Controls 2.76 cfs @ 5.52 fps)
-Open Grate on Control Structure ( Controls 0.00 cfs)
§econdary OutFlow Max=0.00 cfs @ 0.00 hrs HW=867.00' (Free Discharge)
5=Emergency Spillway (Controls 0.00 cfs)
2010-01-21_Wal-Mart Pond Type 11 24-hr 10 year, 24-hour Rainfall=5.10"
Prepared by Kimley-Horn and Associates, Inc. Printed 2/2/2010
HydroCAD@ 9.00 s/n 05123 @2009 HydroCAD Software Solutions LLC Page 4
Summary for Pond 5P: Outfall 1
Inflow Area = 16.860 ac, 0.00% Impervious, Inflow Depth > 1.53" for 10 year, 24-hour event
Inflow = 5.12 cfs @ 12.01 hrs, Volume= 2.155 of
Primary = 5.12 cfs @ 12.01 hrs, Volume= 2.155 af, Atten= 0%, Lag= 0.0 min
Routing by Stor-Ind method, Time Span= 0.00-20.00 hrs, dt= 0.05 hrs
2010-01-21_Wal-Mart Pond Type 1124-hr 25 year, 24-hour Rainfall=6.09"
Prepared by Kimley-Horn and Associates, Inc. Printed 2/2/2010
HydroCAD@ 9.00 s/n 05123 @2009 HydroCAD Software Solutions LLC Page 5
Time span=0.00-20.00 hrs, dt=0.05 hrs, 401 points
Runoff by SCS TR-20 method, UH=SCS
Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method
Subcatchment 1S: Pre-development Runoff Area= 17.060 ac 0.00% Impervious Runoff Depth>1.31"
Tc=27.3 min CN=54 Runoff=20.10 cfs 1.864 of
Subcatchment 2S: Post-development Runoff Area=14.840 ac 0.00% Impervious Runoff Depth>4.87"
Tc=5.0 min CN=92 Runoff=124.25 cfs 6.018 of
Subcatchment 3S: Undetained Post-developmentRunoff Area=2.020 ac 0.00% Impervious Runoff Depth>1.40"
Tc=5.0 min CN=55 Runoff=5.48 cfs 0.236 of
Pond 4P: Wet Detention Pond 1 Peak Elev=871.96' Storage=167,795 cf Inflow=124.25 cfs 6.018 of
Primary=12.52 cfs 2.992 of Secondary=0.00 cfs 0.000 of Outflow=12.52 cfs 2.992 of
Pond 5P: Outfall 1
Inflow= 13.29 cfs 3.228 of
Primary=13.29 cfs 3.228 of
Total Runoff Area = 33.920 ac Runoff Volume = 8.118 of Average Runoff Depth = 2.87'
100.00% Pervious = 33.920 ac 0.00% Impervious = 0.000 ac
2010-01-21_Wal-Mart Pond Type 11 24-hr 25 year, 24-hour Rainfall=6.09"
Prepared by Kimley-Horn and Associates, Inc. Printed 2/2/2010
HydroCAD® 9.00 s/n 05123 @2009 HydroCAD Software Solutions LLC Pace 6
Summary for Subcatchment 1 S: Pre-development
Runoff = 20.10 cfs @ 12.25 hrs, Volume= 1.864 af, Depth> 1.31"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 25 year, 24-hour Rainfall=6.09"
Area (ac) CN Description
17.060 54
17.060 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
27.3 Direct Entry, see spreadsheet
Summary for Subcatchment 2S: Post-development
Runoff = 124.25 cfs @ 11.95 hrs, Volume= 6.018 af, Depth> 4.87'
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 25 year, 24-hour Rainfall=6.09"
Area (ac) CN Description
14.840 92
14.840 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry,
Summary for Subcatchment 3S: Undetained Post-development
Runoff = 5.48 cfs @ 11.97 hrs, Volume= 0.236 af, Depth> 1.40"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 25 year, 24-hour Rainfall=6.09"
Area (ac) CN Description
2.020 55
2.020 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry,
2010-01-21 Wal-Mart Pond Type 11 24-hr 25 year, 24-hour Rainfall=6.09"
Prepared by Kimley-Horn and Associates, Inc. Printed 2/2/2010
. HydroCADO 9.00 s/n 05123 © 2009 HydroCAD Software Solutions LLC Page 7
Sul
Inflow Area = 14.840 ac,
Inflow = 124.25 cfs @
Outflow = 12.52 cfs @
Primary = 12.52 cfs @
Secondary = 0.00 cfs @
mmary for Pond 4P: Wet Detention Pond 1
0.00% Impervious, Inflow Depth > 4.87" for 25 year, 24-hour event
11.95 hrs, Volume= 6.018 of
12.34 hrs, Volume= 2.992 af, Atten= 90%, Lag= 23.3 min
12.34 hrs, Volume= 2.992 of
0.00 hrs, Volume= 0.000 of
Routing by Stor-Ind method, Time Span= 0.00-20.00 hrs, dt= 0.05 hrs
Peak Elev= 871.96'@ 12.34 hrs Surf.Area= 41,429 sf Storage= 167,795 cf
Plug-Flow detention time= 236.7 min calculated for 2.985 of (50% of inflow)
Center-of-Mass det. time= 150.0 min ( 889.6 - 739.6 )
Volume Invert Avail.Storage Storage Description
- '
#1 867.00 212,28 9 cf Custom Stage Data (Prismatic) Listed below (Recalc)

Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic-feet) (cubic-feet)
867.00 24,268 0 0
868.00 29,605 26,937 26,937
869.00 32,538 31,072 58,008
870.00 35,544 34,041 92,049
- 871.00 38,750 37,147 129,196
872.00 41,532 40,141 169,337
873.00 44,371 42,952 212,289
Device Routing Invert Outlet Devices
#1 Primary 866.00' 24.0" Round Culvert L= 50.4' RCP, groove end projecting, Ke= 0.200
Outlet Invert= 864.00' S= 0.03977' Cc= 0.900
n= 0.011 Concrete pipe, straight & clean
#2 Device 1 867.00' 2.9" Vert. Water Quality Orifice C= 0.600
#3 Device 1 870.00'
' 12.0" W x 6.0" H Vert. Water Quantity Control Weir C=0.600
'
'
#4 Device 1 871.60 14.0
long x 0.5
breadth Open Grate on Control Structure
Head (feet) 0.20 0.40 0.60 0.80 1.00
Coef. (English) 2.80 2.92 3.08 3.30 3.32
#5 Secondary 872.00' 25.0' long x 30.0' breadth Emergency Spillway
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
_ Coef. (English) 2.68 2.70 2.70 2.64 2.63 2.64 2.64 2.63
Primary OutFlow Max=12.49 cfs @ 12.34 hrs HW=871.96' (Free Discharge)
t-1=Culvert (Passes 12.49 cfs of 42.12 cfs potential flow)
2=Water Quality Orifice (Orifice Controls 0.49 cfs @ 10.59 fps)
3=Water Quantity Control Weir (Orifice Controls 3.15 cfs @ 6.30 fps)
=Open Grate on Control Structure (Weir Controls 8.85 cfs @ 1.74 fps)
Secondary OutFlow Max=0.00 cfs @ 0.00 hrs HW=867.00' (Free Discharge)
t-5=Emergency Spillway ( Controls 0.00 cfs)
2010-01-21 Wal-Mart Pond Type 11 24-hr 25 year, 24-hour Rainfall=6.09"
Prepared by Kimley-Horn and Associates, Inc. Printed 2/2/2010
HydroCAD® 9.00 s/n 05123 @2009 HydroCAD Software Solutions LLC Page 8
Summary for Pond 5P: Outfall 1
s
Inflow Area = 16.860 ac, 0.00% Impervious, Inflow Depth > 2.30" for 25 year, 24-hour event -
Inflow = 13.29 cfs @ 12.32 hrs, Volume= 3.228 of
Primary = 13.29 cfs @ 12.32 hrs, Volume= 3.228 af, Atten= 0%, Lag= 0.0 min
Routing by Stor-Ind method, Time Span= 0.00-20.00 hrs, dt= 0.05 hrs
HYDROCAD HYDROLOGY REPORTS
1-YEAR, 10-YEAR, 25-YEAR EVENTS
WET DETENTION POND 2
31 URMWA TER MANAGEMENT & EROSION CONTROL CALCULATIONS
Troutman Towne Center, Troutman, North Carolina
1S
Pre-development
2S
Post-deqrlopment
4P
3S) Wet Deter -on Pond 2
Undetained 5P
Post-development
Outfall 1
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Subca Reach on Link
2010-02-01-Phase 1 Pond Type 1124-hr 1 year, 24-hour Rainfall=2.85"
Prepared by Kimley-Horn and Associates, Inc. Printed 2/2/2010
HydroCAD® 9.00 s/n 05123 @2009 HydroCAD Software Solutions LLC Page 2
Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points
Runoff by SCS TR-20 method, UH=SCS
Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method
Subcatchment 1S: Pre-development Runoff Area=30.740 ac 0.00% Impervious Runoff Depth>0.37"
Tc=44.3 min CN=65 Runoff=6.04 cfs 0.949 of
Subcatchment 2S: Post-development Runoff Area=36.470 ac 0.00% Impervious Runoff Depth>1.22"
Tc=5.0 min CN=83 Runoff=87.20 cfs 3.701 of
Subcatchment 3S: Undetained Post-development Runoff Area= 1.060 ac 0.00% Impervious Runoff Depth>0.11"
Tc=5.0 min CN=54 Runoff=0.04 cfs 0.009 of
Pond 4P: Wet Detention Pond 2 Peak Elev=873.73' Storage=112,558 cf Inflow=87.20 cfs 3.701 of
Primary=2.37 cfs 1.298 of Secondary=0.00 cfs 0.000 of Outflow=2.37 cfs 1.298 of
Pond 5P: Outfall 1
Inflow=2.38 cfs 1.307 of
Primary=2.38 cfs 1.307 of
Total Runoff Area = 68.270 ac Runoff Volume = 4.660 of Average Runoff Depth = 0.82"
100.00% Pervious = 68.270 ac 0.00% Impervious = 0.000 ac
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2010-02-01_Phase 1 Pond Type 1124-hr 1 year, 24-hour Rainfall=2.85"
Prepared by Kimley-Horn and Associates, Inc. Printed 2/2/2010
HydroCAD® 9.00 s/n 05123 @2009 HydroCAD Software Solutions LLC Page 3
Summary for Subcatchment 1S: Pre-development
Runoff = 6.04 cfs @ 12.54 hrs, Volume= 0.949 af, Depth> 0.37'
Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 1 year, 24-hour Rainfall=2.85'
Area (ac) CN Description
30.740 65
30.740 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
44.3 Direct Entry, see spreadsheet
Subcatchment 1S: Pre-development
Hydrograph
¦ Runoff
6.04 cfs
6 TYpe 11 24,-hr I year
24-hour
5 Rainfall=2.85''
Runoff Area=30.740 ac
4
Runoff Volume=0.949 a
a 3
Runoff Depth>0.37"
TO=44.3 min
2 CN=65
1.
0
5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Time (hours)
2010-02-01-Phase 1 Pond Type 1124-hr 1 year, 24-hour Rainfall=2.85"
Prepared by Kimley-Horn and Associates, Inc. Printed 2/2/2010
HydroCAD® 9.00 s/n 05123 @2009 HydroCAD Software Solutions LLC Page 4
Summary for Subcatchment 2S: Post-development
[49] Hint: Tc<2dt may require smaller dt
Runoff = 87.20 cfs @ 11.96 hrs, Volume= 3.701 af, Depth> 1.22"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 1 year, 24-hour Rainfall=2.85"
Area (ac) CN Description
36.470 83
36.470 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry,
Subcatchment 2S: Post-development
Hydrograph
90 87.20 cfs
85 Type II 24-hr 1 year
80
75 24-hour
70 Rainfall2.85"
65
60 Runoff Area=36.470 ac
w 55 '
Runoff Volume=3.701of
v 50
° 45 Runoff Depth>1.22"
U. 40
35 Tc=5.0 min
30-
25" CN=83
-
20
15
¦ Runoff
5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Time (hours)
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2010-02-01_Phase 1 Pond Type 1124-hr 1 year, 24-hour Rainfall=2.85"
Prepared by Kimley-Horn and Associates, Inc. Printed 2/2/2010
HydroCAD® 9.00 s/n 05123 @2009 HydroCAD Software Solutions LLC Page 5
Summary for Subcatchment 3S: Undetained Post-development
[49] Hint: Tc<2dt may require smaller dt
Runoff = 0.04 cfs @ 12.05 hrs, Volume= 0.009 af, Depth> 0.11"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 1 year, 24-hour Rainfall=2.85"
Area (ac) CN Description
1.060 54
1.060 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry,
Subcatchment 3S: Undetained Post-development
Hydrograph
0.046 ¦ Runoff
0.044 0.04
fs
C
0.042 - - Type 1124: hr I year
0.04
0.038
24-hour
0.036
0.034
-Rainfall=2.85"
0.032
003 Runoff Area'=1
060 ac
.. 0.028 .
0.026 _ Runoff Volume-0.
- X09 of
0.024
0 0.022
U. Runoff Depth>0.11'.
0.02
0.018
T=5rV min
0.016
0.014
N=54
0.012
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0.01-
0.008-
0.006-
0.004-
0.002
0
5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Time (hours)
2010-02-01-Phase 1 Pond Type 1124-hr 1 year, 24-hour Rainfall=2.85"
Prepared by Kimley-Horn and Associates, Inc. Printed 2/2/2010
HydroCAM 9.00 s/n 05123 @2009 HydroCAD Software Solutions LLC Page 6
Summary for Pond 4P: Wet Detention Pond 2
Inflow Area = 36.470 ac, 0.00% Impervious, Inflow Depth > 1.22" for 1 year, 24-hour event
Inflow = 87.20 cfs @ 11.96 hrs, Volume= 3.701 of
Outflow = 2.37 cfs @ 15.04 hrs, Volume= 1.298 af, Atten= 97%, Lag= 185.0 min
Primary = 2.37 cfs @ 15.04 hrs, Volume= 1.298 of
Secondary = 0.00 cfs @ 5.00 hrs, Volume= 0.000 of
Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
Peak Elev= 873.73'@ 15.04 hrs Surf.Area= 68,965 sf Storage= 112,558 cf
Plug-Flow detention time= 260.9 min calculated for 1.298 of (35% of inflow)
Center-of-Mass det. time= 173.4 min ( 964.3 - 790.9 )
Volume Invert Avail.Storage Storage Description
#1 872.00' 316,119 cf Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic-feet) (cubic-feet)
872.00 59,041 0 0
873.00 66,546 62,794 62,794
874.00 69,840 68,193 130,987
875.00 73,190 71,515 202,502
876.00 76,590 74,890 277,392
876.50 78,320 38,728 316,119
Device Routing Invert Outlet Devices
#1 Primary 868.00' 24.0" Round Outlet Pipe
L= 77.0' RCP, groove end projecting, Ke= 0.200
Outlet Invert= 867.00' S=0.0130'/' Cc= 0.900
n= 0.011 Concrete pipe, straight & clean
#2 Device 1 872.00' 5.0" Vert. Water Quality Orifice C= 0.600
#3 Device 1 873.40' 30.0" W x 12.0" H Vert. Water Quantity Control Weir C=0.600
#4 Device 1 874.85' 14.0' long x 0.5' breadth Open Grate on Control Structure
Head (feet) 0.20 0.40 0.60 0.80 1.00
Coef. (English) 2.80 2.92 3.08 3.30 3.32
#5 Secondary 875.50' 55.0' long x 55.0' breadth Emergency Spillway
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Coef. (English) 2.68 2.70 2.70 2.64 2.63 2.64 2.64 2.63
Primary OutFlow Max=2.36 cfs @ 15.04 hrs HW=873.73' (Free Discharge)
t-1=Outlet Pipe (Passes 2.36 cfs of 39.93 cfs potential flow)
2=Water Quality Orifice (Orifice Controls 0.81 cfs @ 5.95 fps)
3=Water Quantity Control Weir (Orifice Controls 1.55 cfs @ 1.86 fps)
-Open Grate on Control Structure (Controls 0.00 cfs)
Secondary OutFlow Max=0.00 cfs @ 5.00 hrs HW=872.00' (Free Discharge)
't-5--Emergency Spillway ( Controls 0.00 cfs)
•
I•
2010-02-01 Phase l Pond Type 11 24-hr 1 year, 24-hour Rainfall=2.85"
Prepared by Kimley-Horn and Associates, Inc. Printed 2/2/2010
HydroCAD® 9.00 s/n 05123 @2009 HydroCAD Software Solutions LLC Page 7
Pond 4P: Wet Detention Pond 2
Hydrograph
¦ Inflow
? Outflow
¦ Primary
? Secondary
5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Time (hours)
2010-02-01 -Phase 1 Pond Type 11 24-hr 1 year, 24-hour Rainfall=2.85"
Prepared by Kimley-Horn and Associates, Inc. Printed 2/2/2010
HydroCAD® 9.00 s/n 05123 © 2009 HydroCAD Software Solutions LLC Page 8
Summary for Pond 5P: Outfall 1
[40] Hint: Not Described (Outflow= Inflow)
Inflow Area = 37.530 ac, 0.00% Impervious, Inflow Depth > 0.42" for 1 year, 24-hour event
Inflow = 2.38 cfs @ 15.03 hrs, Volume= 1.307 of
Primary = 2.38 cfs @ 15.03 hrs, Volume= 1.307 af, Atten= 0%, Lag= 0.0 min
Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
Pond 5P: Outfall 1
Hydrograph
¦ Inflow
¦ Primary
2
F
w
v
3
0
U.
1
0
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Time (hours)
2010-02-01_Phase 1 Pond Type 11 24-hr 10 year, 24-hour Rainfall=5.10"
Prepared by Kimley-Horn and Associates, Inc. Printed 2/2/2010
HydroCAD@)9.00 s/n 05123 @2009 HydroCAD Software Solutions LLC Paae 1
Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points
Runoff by SCS TR-20 method, UH=SCS
Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method
Subcatchment 1S: Pre-development Runoff Area=30.740 ac 0.00% Impervious Runoff Depth>1.53"
Tc=44.3 min CN=65 Runoff=32.66 cfs 3.912 of
Subcatchment 2S: Post-development Runoff Area=36.470 ac 0.00% Impervious Runoff Depth>3.04"
Tc=5.0 min CN=83 Runoff=209.26 cfs 9.240 of
Subcatchment 3S: Undetained Post-development Runoff Area=1.060 ac 0.00% Impervious Runoff Depth>0.85"
Tc=5.0 min CN=54 Runoff=1.66 cfs 0.075 of
Pond 4P: Wet Detention Pond 2 Peak Elev=875.28' Storage=223,486 cf Inflow=209.26 cfs 9.240 of
Primary=27.07 cfs 6.439 of Secondary=0.00 cfs 0.000 of Outflow=27.07 cfs 6.439 of
Pond 5P: Outfall 1
Inflow=27.37 cfs 6.514 of
Primary=27.37 cfs 6.514 of
Total Runoff Area = 68.270 ac Runoff Volume =13.227 of Average Runoff Depth = 2.32"
100.00% Pervious= 68.270 ac 0.00% Impervious = 0.000 ac

2010-02-01-Phase 1 Pond Type 1124-hr 10 year, 24-hour Rainfall=5.10"
Prepared by Kimley-Horn and Associates, Inc. Printed 2/2/2010
HydroCADO 9.00 s/n 05123 @2009 HydroCAD Software Solutions LLC Page 2
Summary for Subcatchment 1 S: Pre-development
Runoff = 32.66 cfs @ 12.45 hrs, Volume= 3.912 af, Depth> 1.53"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 10 year, 24-hour Rainfall=5.10"
Area (ac) CN Description
30.740 65
30.740 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
44.3 Direct Entry, see spreadsheet
Summary for Subcatchment 2S: Post-development
Runoff = 209.26 cfs @ 11.95 hrs, Volume= 9.240 af, Depth> 3.04"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 10 year, 24-hour Rainfall=5.10"
Area (ac) CN Description
36.470 83
36.470 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry,
Summary for Subcatchment 3S: Undetained Post-development
Runoff = 1.66 cfs @ 11.98 hrs, Volume= 0.075 af, Depth> 0.85"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 10 year, 24-hour Rainfall=5.10"
Area (ac) CN Description
1.060 54
1.060 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry,

2010-02-01 Phase 1 Pond Type 11 24-hr 10 year, 24-hour RainfaU=5.10"
Prepared by Kimley-Horn and Associates, Inc. Printed 2/2/2010
- HydroCAD® 9.00 s/n 05123 © 2009 HydroCAD Software Solutions LLC Page 3

Summary for Pond 4P: Wet Detention Pond 2

• Inflow Area = 36.470 ac, 0.00% Impervious, Inflow Depth > 3.04" for 10 year, 24-hour event
Inflow = 209.26 cfs @ 11.95 hrs, Volume= 9.240 of
Outflow = 27.07 cfs @ 12.22 hrs, Volume= 6.439 af, Atten= 87%, Lag= 16.0 min
- Primary = 27.07 cfs @ 12.22 hrs, Volume= 6.439 of
Secondary = 0.00 cfs @ 5.00 hrs, Volume= 0.000 of

- Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
'
Peak Elev= 875.28
@ 12.22 hrs Surf.Area= 74,158 sf Storage= 223,486 cf

- Plug-Flow detention time= 172.2 min calculated for 6.418 of (69% of inflow)
Center-of-M ass det. time= 106.3 min ( 877.2 - 770.9 )

- Volume Invert Avail.Storage Storage Description
'
#1 872.00
316,119 cf Custom Stage Data (Prismatic) Listed below (Recalc)

Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic-feet) (cubic-feet)
i 872.00 59,041 0 0
- 873.00 66,546 62,794 62,794
874.00 69,840 68,193 130,987
875.00 73,190 71,515 202,502
- 876.00 76,590 74,890 277,392
876.50 78,320 38,728 316,119

Device Routing Invert Outlet Devices
#1 Primary 868.00' 24.0" Round Outlet Pipe
L= 77.0' RCP, groove end projecting, Ke= 0.200
Outlet Invert= 867.00' S=0.0130'/' Cc= 0.900
n= 0.011 Concrete pipe, straight & clean
#2 Device 1 872.00' 5.0" Vert. Water Quality Orifice C= 0.600
#3 Device 1 873.40' 30.0" W x 12.0" H Vert. Water Quantity Control Weir C= 0.600
#4 Device 1 874.85' 14.0' long x 0.5' breadth Open Grate on Control Structure
Head (feet) 0.20 0.40 0.60 0.80 1.00
Coef. (English) 2.80 2.92 3.08 3.30 3.32
#5 Secondary 875.50' 55.0' long x 55.0' breadth Emergency Spillway
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Coef. (English) 2.68 2.70 2.70 2.64 2.63 2.64 2.64 2.63
Primary OutFlow Max=27.02 cfs @ 12.22 hrs HW=875.28' (Free Discharge)
t1=Out1et Pipe (Passes 27.02 cfs of 46.01 cfs potential flow)
2=Water Quality Orifice (Orifice Controls 1.15 cfs @ 8.44 fps)
13=Water Quantity Control Weir (Orifice Controls 14.08 cfs @ 5.63 fps)
-Open Grate on Control Structure (Weir Controls 11.79 cfs @ 1.94 fps)
Secondary OutFlow Max=0.00 cfs @ 5.00 hrs HW=872.00' (Free Discharge)
t-5=Emergency Spillway (Controls 0.00 cfs)
2010-02-01-Phase 1 Pond Type 1124-hr 10 year, 24-hour Rainfall=5.10"
Prepared by Kimley-Horn and Associates, Inc. Printed 2/2/2010
HydroCADO 9.00 s/n 05123 @2009 HydroCAD Software Solutions LLC Page 4
Summary for Pond 5P: Ouffall 1
Inflow Area = 37.530 ac, 0.00% Impervious, Inflow Depth > 2.08" for 10 year, 24-hour event
Inflow = 27.37 cfs @ 12.22 hrs, Volume= 6.514 of
Primary = 27.37 cfs @ 12.22 hrs, Volume= 6.514 af, Atten= 0%, Lag= 0.0 min
Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
2010-02-01-Phase 1 Pond Type 1124-hr 25-year, 24-hour Rainfall=6.09"
Prepared by Kimley-Horn and Associates, Inc. Printed 2/2/2010
HydroCADO 9.00 s/n 05123 @2009 HydroCAD Software Solutions LLC Pape 5
Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points
Runoff by SCS TR-20 method, UH=SCS
Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method
Subcatchment 1S: Pre-development Runoff Area=30.740 ac 0.00% Impervious Runoff Depth>2.17"
Tc=44.3 min CN=65 Runoff=47.44 cfs 5.546 of
Subcatchment 2S: Post-development Runoff Area=36.470 ac 0.00% Impervious Runoff Depth>3.90"
Tc=5.0 min CN=83 Runoff=264.34 cfs 11.853 of
Subcatchment 3S: Undetained Post-development Runoff Area=1.060 ac 0.00% Impervious Runoff Depth>1.33"
Tc=5.0 min CN=54 Runoff=2.70 cfs 0.117 of
Pond 4P: Wet Detention Pond 2 Peak Elev=875.87' Storage=267,395 cf Inflow=264.34 cfs 11.853 of
Primary=48.10 cfs 8.422 of Secondary=33.25 cfs 0.516 of Outflow=81.35 cfs 8.938 of
Pond 5P: Outfall 1
Inflow=82.21 cfs 9.055 of
Primary=82.21 cfs 9.055 of
Total Runoff Area = 68.270 ac Runoff Volume =17.517 of Average Runoff Depth = 3.08"
100.00% Pervious = 68.270 ac 0.00% Impervious = 0.000 ac
2010-02-01 -Phase 1 Pond Type 1124-hr 25-year, 24-hour Rainfall=6.09"
Prepared by Kimley-Horn and Associates, Inc. Printed 2/2/2010
HydroCADO 9.00 s/n 05123 @2009 HydroCAD Software Solutions LLC Page 6
Summary for Subcatchment 1S: Pre-development
Runoff = 47.44 cfs @ 12.44 hrs, Volume= 5.546 af, Depth> 2.17'
Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 25-year, 24-hour Rainfall=6.09"
Area (ac) CN Description
30.740 65
30.740 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
44.3 Direct Entry, see spreadsheet
Summary for Subcatchment 2S: Post-development
Runoff = 264.34 cfs @ 11.95 hrs, Volume= 11.853 af, Depth> 3.90"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 25-year, 24-hour Rainfall=6.09"
Area (ac) CN Description
36.470 83
36.470 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry,
Summary for Subcatchment 3S: Undetained Post-development
Runoff = 2.70 cfs @ 11.97 hrs, Volume= 0.117 af, Depth> 1.33"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 25-year, 24-hour Rainfall=6.09"
Area (ac) CN Description
1.060 54
1.060 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry,
•
•
•
i
i 2010-02-01 Phase 1 Pond Type ll 24-hr 25-year, 24-hour Rainfall=6.09"
Prepared by Kimley-Horn and Associates, Inc. Printed 2/2/2010
i HydroCADO 9.00 s/n 05123 @2009 HydroCAD Software Solutions LLC Pace 7
Summary for Pond 4P: Wet Detention Pond 2
Inflow Area = 36.470 ac, 0.00% Impervious, Inflow Depth > 3.90" for 25-year, 24-hour event
Inflow = 264.34 cfs @ 11.95 hrs, Volume= 11.853 of
Outflow = 81.35 cfs @ 12.09 hrs, Volume= 8.938 af, Atten= 69%, Lag= 8.1 min
Primary = 48.10 cfs @ 12.09 hrs, Volume= 8.422 of
Secondary = 33.25 cfs @ 12.09 hrs, Volume= 0.516 of
Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
Peak Elev= 875.87'@ 12.09 hrs Surf.Area= 76,145 sf Storage= 267,395 cf
Plug-Flow detention time= 147.6 min calculated for 8.908 of (75% of inflow)
Center-of-Mass det. time= 87.9 min ( 853.0 - 765.1 )
Volume Invert Avail.Storage Storage Description
-
#1 872.00' 316,119 cf Custom Stage Data (Prismatic) Listed below (Recalc)
•
i Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic-feet) (cubic-feet)
i 872.00 59,041 0 0
i 873.00 66,546 62,794 62,794
874.00 69,840 68,193 130,987
i 875.00 73,190 71,515 202,502
i 876.00 76,590 74,890 277,392
876.50 78,320 38,728 316,119
•
Device Routing Invert Outlet Devices
i
#1 Primary 868.00' 24.0" Round Outlet Pipe
L= 77.0' RCP, groove end projecting, Ke= 0.200
. Outlet Invert= 867.00' S= 0.0130'/' Cc= 0.900
n= 0.011 Concrete pipe, straight & clean
#2 Device 1 872.00' 5.0" Vert. Water Quality Orifice C= 0.600
. #3 Device 1 873.40'
' 30.0" W x 12.0" H Vert. Water Quantity Control Weir C=0.600
'
'
#4 Device 1 874.85 14.0
long x 0.5
breadth Open Grate on Control Structure
Head (feet) 0.20 0.40 0.60 0.80 1.00

' Coef. (English) 2.80 2.92 3.08 3.30 3.32
'
'
#5 Secondary 875.50 55.0
long x 55.0
breadth Emergency Spillway
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Coef. (English) 2.68 2.70 2.70 2.64 2.63 2.64 2.64 2.63
Primary OutFlow Max=48.07 cfs @ 12.09 hrs HW=875.86' (Free Discharge)
t1=Outlet Pipe (Barrel Controls 48.07 cfs @ 15.30 fps)
2=Water Quality Orifice (Passes < 1.25 cfs potential flow)
13=Water Quantity Control Weir (Passes < 16.81 cfs potential flow)
-Open Grate on Control Structure (Passes < 47.29 cfs potential flow)
Secondary OutFlow Max=32.25 cfs @ 12.09 hrs HW=875.86' (Free Discharge)
t5=Emergency Spillway (Weir Controls 32.25 cfs @ 1.62 fps)
2010-02-01-Phase 1 Pond Type 11 24-hr 25-year, 24-hour Rainfall=6.09"
Prepared by Kimley-Horn and Associates, Inc. Printed 2/2/2010
HydroCADO 9.00 s/n 05123 © 2009 HydroCAD Software Solutions LLC Page 8
Summary for Pond 5P: Ouffall 1
Inflow Area = 37.530 ac, 0.00% Impervious, Inflow Depth > 2.90" for 25-year, 24-hour event
Inflow = 82.21 cfs @ 12.09 hrs, Volume= 9.055 of
Primary = 82.21 cfs @ 12.09 hrs, Volume= 9.055 af, Atten= 0%, Lag= 0.0 min
Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs