20140721 Ver 1_2014-07-09 Level Spreader Design_20140711

LEVEL SPREADER DESIGN
V U E 64
DDV-13010
RALEIGH, NORTH CAROLINA
DATE: JULY 2014
Mh-
A'
Raleigh/Durharn m 2905 Meridian Parkway a Durham, NC 27713
Charlotte m 11301 Carmel Commons Blvd m Suite 111 m Charlotte, NC 28226
McAdamsCo,corn
Oesigning Tornort,ow's InfrastrocItIfe & Communities

Le VC � 'S e re 4t 610, 4- 1 Permit Number:
(to be provided WQJ
Drainage Area Number; 4S--d
Filter Strip, Restored Riparian Buffer and Level Spreader
Operation and Maintenance Agreement
I will keep a maintenance record on this BMP. This maintenance record will be kept in a
log in a known set location. Any deficient BMP elements noted in the inspection will be
corrected, repaired or replaced immediately. These deficiencies can affect the integrity
of structures, safety of the public, and the removal efficiency of the BMP.
Important maintenance procedures:
- Immediately after the filter strip is established, any newly planted vegetation
will be watered twice weekly if needed until the plants become established
(commonly six weeks).
- Once a year, the filter strip will be reseeded to maintain a dense growth of
vegetation
- Stable groundcover will be maintained in the drainage area to reduce the
sediment load to the vegetation.
- Two to three times a year, grass filter strips will be mowed and the clippings
harvested to promote the growth of thick vegetation with optimum pollutant
removal efficiency. Turf grass should not be cut shorter than 3 to 5 inches and
may be allowed to grow as tall as 12 inches depending on aesthetic requirements
(NIPC,1993). Forested filter strips do not require this type of maintenance.
- Once a year, the soil will be aerated if necessary.
- Once a year, soil pH will be tested and Time will be added if necessary.
After the filter strip is established, it will be inspected quarterly and within 24 hours
after every storm event greater than 1.0 inch (or 1.5 inches if in a Coastal County).
Records of operation and maintenance will be kept in a known set location and will be
available upon request.
Inspection activities shall be performed as follows. Any problems that are found shall
be repaired immediately.
BMP element:
Potential problem;
How I will remediate the roblem:
The entire filter strip
Trash /debris is present.
Remove the trash /debris.
__system
The flow splitter device
(if applicable)
The flow splitter device is
clogged.
Unclog the conveyance and dispose
of any sediment off -site.
The flow splitter device is
Make any necessary repairs or
damaged.
replace if damage is too Iarge for
repair
Form SWU401 -Level Spreader, Filter Strip, Restored Riparian Buffer O &M -Rev.3 Page I of 4

BMP element:
Potential problem:
How 1 will remediate the problem:
The swale and the level
lip
The swale is clogged with
sediment.
Remove the sediment and dispose
of it off-site.
The Ievel lip is cracked,
Repair or replace lip.
settled, undercut, eroded or
otherwise damaged.
There is erosion around the
Regrade the soil to create a berm
end of the IeveI spreader that
that is higher than the level lip, and
shows stormwater has
then plant a ground cover and
bypassed it.
water until it is established. Provide
lime and a one -time fertilizer
application,
Trees or shrubs have begun
Remove them,
to grow on the swale or just
downslo e of the level lip.
The bypass channel
Areas of bare soil and /or
Regrade the soil if necessary to
erosive gullies have formed.
remove the gully, and then
reestablish proper erosion control.
Turf reinforcement is
Study the site to see if a larger
damaged or ripap is rolling
bypass channel is needed (enlarge if
downhill.
necessary). After this, reestablish
the erosion control material.
The filter strip
Grass is too short or too long
Maintain grass at a height of
if applicable).
a roximatel three to six inches.
Areas of bare soil and /or
Regrade the soil if necessary to
erosive gullies have formed.
remove the gully, and then plant a
ground cover and water until it is
established. Provide lime and a
one -time fertilizer application.
Sediment is building up on
Remove the sediment and
the filter strip.
restabilize the soil with vegetation if
necessary. Provide lime and a one-
time fertilizer application.
Plants are desiccated.
Provide additional irrigation and
fertilizer as needed.
Plants are dead, diseased or
Determine the source of the
dying.
problem: soils, hydrology, disease,
etc. Remedy the problem and
replace plants. Provide a one -time
fertilizer application.
Nuisance vegetation is
Remove vegetation by hand if
choking out desirable species.
possible. If pesticide is used, do not
allow it to get into the receiving
water.
The receiving water
Erosion or other signs of
Contact the NC Division of Water
damage have occurred at the
Quality local Regional Office, or the
outlet. 1
401 Oversight Unit at 919- 733 -1786.
Form S WU40I -Level Spreader, Filter Strip, Restored Riparian Buffer O &M -Rev.3 Page 2 of 4

Permit Number:
I acknowledge and agree by my signature below that I am responsible for the
performance of the maintenance procedures listed above. I agree to notify DWQ of any
problems with the system or prior to any changes to the system or responsible party.
Project name:Vue
BMP drainage area number: /_ Y—
Print nameTred S. Hazel
Title:Vice President of Morrow Investors, Inc., Manager of DD Mellowfield II, LLC,
Address:403 Corpo�
Phone: [phone]
Signature::
Date: d"
Note: The legally responsible party should not be a homeowners association unless more than 50% of
the lots have been sold and a resident of the subdivision has been named the president.
I, -ne berms A. �'_n , a Notary Public for the State of
f , , County of 4Et , ru , do hereby certify that
personally appeared before me this
day of c , and acknowledge the due execution of the
forgoing filter strip, riparian buffer, and /or level spreader maintenance requirements.
Witness my hand and official seal,
SEAL
My CxrOMIM EWM JWKWY 39, 2096
My commission expires
Form SWU401 -Level Spreader, Filter Strip, Restored Riparian Buffer O &M -Rev.3 Page 3 of 4

Permit Number:
(to be provided by DWQ)
Form SWU401 -Level Spreader, Filter Strip, Restored Riparian Buffer O &M -Rev.3 Page 4 of 4

VUE 64
(FORMERLY AVENUES II)
RALEIGH, NORTH CAROLINA
LEVEL SPREADER DESIGN
PROJECT NUMBER:
DESIGNED BY:
DATE:
0 I
DDV -13010
JOSH SHINN, EI
JULY 2014
2905 MERIDIAN PARKWAY
DURHAM, NORTH CAROLINA 27713
NC Lic. # C -0293

Vue 64
Level Spreader Design
General Descriotion
Looted off of Meadow Wood Boulevard, on the west corner of the intersection of Interstate 440
and Capital Boulevard, in Raleigh, North Carolina, is the proposed multifamily housing
development currently known as Vue 64 (formerly known as Avenues II). Development on this
site will consist of the construction of multifamily housing units, along with associated streets,
sidewalks, utilities, stormwater management, and other infrastructure.
The proposed development is located within the Neuse River basin and will be subject to the
stormwater management requirements set forth in Section 10, Chapter 9 of the City of Raleigh
regulations. Per City of Raleigh regulations, stormwater management on this site shall address
two primary issues: (1) peak discharge rates and (2) water quality management.
1. Stormwater Runoff Controls [Section 10 -90231
(a) Runoff limitation
The peak stormwater runoff leaving any site for the two-year and ten year storms shall be
no greater for post- development conditions than pre- development conditions. The same
methodologies used to calculate stormwater runoff must be used for both pre -
development and post- development conditions (Section 10- 9023a).
For any land disturbing activity, as defined in Part 10 Chapter 5, the peak stormwater
runoff leaving the site at each discharge point for the two-year storm shall be no greater
during construction than for pre- development conditions. However, this regulation shall
not be applicable when the development site conforms to all of the following:
(1) The disturbed acreage is less than five (5) acres;
(2) The two-year peak discharge for the disturbed condition, for all points of
discharge, is less than ten (10) per cent of the peak discharge from the
contributing watershed as measured at the nearest receiving watercourse.
(b) Exemptions.
In addition to those activities exempted by §10- 9003(b) and §10 -9021, the stormwater
runoff control requirements of this section shall not apply to one (1) or more of the
following:
(1) The increase in peak stormwater runoff between pre - development and post -
development conditions for the two-year and ten-year storms is ten (10) percent
or less at each point of discharge.
(2) The maximum impervious surface coverage of the lot, including any existing
impervious surfaces, is no more than fifteen (1 S) per cent and the remaining
pervious portions of the lot are utilized to convey and control the stormwater
runoff of the lot to the maximum extent practical. Any lot which is exempted from
the runoff control requirements by subsection (b)(2), shall comply with all the
requirements of subsection (a) whenever:
a. The exempted lot is subdivided; or
b. The exempted lot size is reduced by recombination; or
c. Impervious surfaces on the exempted lot equal or exceed fifteen (I5)
per cent.

(3) Compliance with the runoff limitations in subsection (a) above would result
in greater adverse downstream impact, such as local flooding, as determined by
City approved engineering studies.
(4) Compliance with the ten-year storm runoff limitations in subsection (a)
above results in no benefit to current and future downstream development, as
determined by City - approved engineering studies.
Projects exempted by subsection (b) shall protect all affected lands and receiving
watercourses from accelerated erosion as defined in Chapter S, Part 10.
2. Nitrogen Reduction [Section 10 -9024
a) Requirements
No development nor any expansion of an existing development, use, facility, building,
structure, nor any new or expanded vehicular surface area shall contribute a nitrogen
export load exceeding three and six tenths (3.6) pounds per acre per year.
b) Payment to North Carolina Riparian Buffer Restoration Fund as an offset
Developers shall have the option of offsetting their nitrogen export load limitations of
subsection (a) above by paying monies to the North Carolina Riparian Buffer Restoration
Fund based on the latest fee adopted by the State. For residential development, a one-
time offset payment may be paid to the North Carolina Riparian Buffer Restoration
Fund to bring the nitrogen export load down from six (6) pounds per acre per year to
three and six - tenths (3.6) pounds per acre per year. For all other developments, a one-
time offset payment may be paid to the North Carolina Riparian Buffer Restoration
Fund to bring the nitrogen export load down from ten (10) pounds per acre per year to
three and six - tenths (3.6) pounds per acre per year. Installation of City approved
stormwater control measures or payments or a combination of both may be used.
Residential developments which exceed nitrogen export loads of six (6) pounds per acre
per year and other developments which exceed nitrogen export loads of ten (10)
pounds per acre per year must install City approved stormwater control measures to
reduce the nitrogen export load of their development to the applicable six (6) or ten (10)
pounds per acre per year limitation to become eligible for payment offsets. All payments
are to be paid to the North Carolina Riparian Buffer Restoration Fund at the time of
subdivision recordation for those subdivisions with an approved unified off -site
stormwater control facilities plan. For all other developments, payments shall be paid to
the North Carolina Riparian Buffer Restoration Fund prior to the issuance of applicable
development permits (Section 10- 9022a -c).
Please note that residential development is defined in Section 10 -9002 as any lot devoted
to single family or duplex land use.
Per Section 10- 9023(b)(4) of the City of Raleigh code, development on this tract is exempt from
the City of Raleigh detention requirements since "compliance with the ten -year storm runoff
limitations in subsection (a) above results in no benefit to current and future downstream
development, as determined by City - approved engineering studies." For this reason, no
stormwater control measure is needed to provide any water quantity control (i.e. detention)
benefit, as this development drains directly to an unnamed tributary to Crabtree Creek.
Per Section 10- 9022(b) of the City of Raleigh code, development on this tract does not require
the installation of a stormwater control measure as the post - development nitrogen loading rate
does not exceed 10 lbs /ac /yr (see Section 5). Offset payments will be made to reach the 3.6

lbs /ac /year target nitrogen loading rate. The diffuse flow requirement due to a buffer necessitates
a level spreader / vegetated filter strip to be provided.
This report contains the design of the proposed level spreader / vegetated filter strip facility that
will be used to treat the site.
Calculation Methodology
1. Rainfall data for the Raleigh, NC region is from NOAA Atlas 14, with a partial duration
series assumption.
2. Using maps contained within the Wake County Soil Surveys, the on- and off -site soils
were determined to be from hydrologic soil group (HSG) B', HSG `C', and HSG `D'
soils.
3. The Rational Method was used to calculate flows to the level spreader / vegetated filter
strip facility. Rational `C' values of 0.95 and 0.35 were assigned for impervious area and
open space, respectively. Open space was assumed to be steep lawn with clay soils. A
composite Rational `C' value was calculated for the drainage area to the level spreader.
4. The on- and off -site topography used in the analysis is from two different sources. They
are as follows:
a. The on -site existing topography is from information provided to The John R.
McAdams Company, Inc. by Riley Surveying, PA.
b. The off -site existing topography is from City of Raleigh GIS topography
information obtained from the City of Raleigh by The John R. McAdams
Company, Inc.
The two sets of data mentioned above were "spliced" together to construct the existing
topography used in the analysis. Please refer to the post- development watershed map for
more information.
5. Final sizing calculations for the proposed level spreader / vegetated filter strip facility
were performed in accordance with the N.C. Stormwater Best Management Practices
manual (NCDENR July 2007). The required design flow for this facility, receiving flow
directly from the drainage area, is the 1 in/hr storm event with larger flows to be
bypassed. The criteria for sizing the level spreader is 10 ft per cfs.
6. A velocity dissipater is provided at the outlet to prevent erosion and scour in the
downstream areas. The dissipater will be constructed using rip rap, underlain with a
woven geotextile filter fabric. The filter fabric is used to minimize the loss of soil
particles beneath the rip rap apron. The dissipater is sized for the 10 -year storm event
using the NYDOT method. It is a permanent feature of the outlet structure.
Discussion of Results — Release Rate Management
Per Section 10- 9023(b)(4) of the City of Raleigh code, development on this tract is exempt from
the City of Raleigh detention requirements since "compliance with the ten -year storm runoff
limitations in subsection (a) above results in no benefit to current and future downstream
development, as determined by City- approved engineering studies." For this reason, no
stormwater control measure is needed to provide any water quantity control (i.e. detention)
benefit, as this development drains directly to an unnamed tributary to Crabtree Creek.

Discussion of Results — Diffuse Flow
Per Section 5 of NC Administrative Code 15A NCAC 02B .0233 Neuse River Basin Protection
and Maintenance of Existing Riparian Buffers, diffuse flow of runoff shall be maintained in the
riparian buffer by dispersing concentrated flow and reestablishing vegetation. Concentrated
runoff from new ditches and manmade conveyances shall be converted to diffuse flow before the
runoff enters the Zone 2 of the riparian buffer. Periodic corrective action to restore diffuse flow
shall be taken if necessary to impede the formation of erosion gullies. Since the proposed project
is located within the Neuse River Basin, it is subject to the diffuse flow requirements.
Per Chapter 8 — "Level Spreader and Vegetative Filter Strip" of the NC DWQ BMP Manual, a
BMP that removes 30% TN and 30% TP may discharge through the buffer via a bypass channel
with a buffer authorization from the DWQ 401 program. However, this project utilizes an
existing channel through the buffer to convey stormwater to the stream channel. A level spreader
has been designed per the NC Stormwater BMP Manual to meet diffuse flow requirements.
Cnnrluvinn
If the development on this tract is built as proposed within this report, then the requirements set
forth in Section 10, Chapter 9 of the City of Raleigh regulations will be met with the
existing /proposed stormwater management facilities. However, modifications to the proposed
development may require that this analysis be revised. Some modifications that would require
this analysis to be revised include:
1. The proposed site impervious surface exceeds the amount accounted for in this report.
2. The post - development watershed breaks change significantly from those used to prepare
this report.
The above modifications may result in the assumptions within this report becoming invalid. The
computations within this report will need to be revisited if any of the above conditions become
apparent as development of the proposed site moves forward.

WDENR
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
401 CERTIFICATION APPLICATION FORM
LEVEL SPREADER - VEGETATED FILTER STRIP (LS -VFS) SUPPLEMENT
This form must be completely filled out, printed, initialed, and submitted.
jig PROJECT INFORMATION ,
`I
Project name
Vue 64 (formerly Avenues ll)
Contact name
Kevin Yates
Phone number
919- 361 -5000
Date
July 7, 2014
Drainage area number
Sub 2 to SWMF
II., DESIGN INFORMATION
The purpose of the LS VFS
Buffer Rule: Diffuse Flow
Stormwater enters LS -VFS from
The drainage area
Type of VFS
Engineered filter strip (graded & sodded, slope < 8 %)
Explanation of any "Other" responses above
If Stormwater Enters the LS -VFS from the Drainage Area
Drainage area
419,918
ft2
Impervious surface area
334,541
ft
Percent impervious
79.67
%
Rational C coefficient
0.83
Peak flow from the 1 in /hr storm
7.98
cis
Time of concentration
5.00
min
Rainfall intensity, 10- yrstorm
7.24
in /hr
Peak flow from the 10 -yr storm
57.79
cfs
Design storm
1 inch /hour storm
Maximum amount of flow directed to the LS -VFS
10
cfs
Is a flow bypass system going to be used?
Y
(Y or N)
Explanation of any "Other" responses above
If Stormwater Enters the LS -VFS from a BMP
Do not complete this section of the form.
Type of BMP
Peak discharge from the BMP during the design storm
cfs
Peak discharge from the BMP during the 10 -year storm
cfs
Do not complete this section of the form.
Maximum capacity of a 100 -foot long LS -VFS
10
cfs
Peak flow directed to the LS -VFS
cfs
Do not complete this section of the form.
Is a flow bypass system going to be used?
(Y or N)
Explanation of any "Other" responses above
Form SW401 - LS -VFS - 29June2012 - Rev. 10 page 1 of 3

LS -VFS Design
Forebay surface area
Depth of forebay at stormwater entry point
Depth of forebay at stormwater exit point
Feet of level lip needed per cfs
Computed minimum length of the level lip needed
Length of level lip provided
Width of VFS
Elevation at downslope base of level lip
Elevation at the end of the VFS that is farthest from the LS
Slope (from level lip to the end of the VFS)
Are any draws present in the VFS?
Is there a collector swale at the end of the VFS?
Bypass System Design (if applicable)
Is a bypass system provided?
Is there an engineered flow splitting device?
Dimensions of the channel (see diagram below):
M
B
W
y (flow depth for 10 -year storm)
freeboard (during the 10 -year storm)
Peak velocity in the channel during the 10 -yr storm
Channel lining material
Does the bypass discharge through a wetland?
Does the channel enter the stream at an angle?
Explanation of any "Other" responses above
N/A sq ft Forebay is adequately sized.
in
Y (Y or N)
Y (Y or N) Please provide plan details of flow splitter & supporting calcs.
ft
ft
ft
ft
ft
ft/sec
N (Y or N)
Y (Y or N)
Level spreader bypass system utilizes a riprap velocity dissipater designed for the 10 year
storm and discharges to an existing draw.
NV
1 B 1
Form SW401 - LS -VFS - 29June2012 - Rev. 10 page 2 of 3
in
10
ft/cfs
100
ft
100
ft
30
ft
242.00
fmsl
241.00
fmsl
3.33
%
N
(Y or N) OK
N
(Y or N)
Y (Y or N)
Y (Y or N) Please provide plan details of flow splitter & supporting calcs.
ft
ft
ft
ft
ft
ft/sec
N (Y or N)
Y (Y or N)
Level spreader bypass system utilizes a riprap velocity dissipater designed for the 10 year
storm and discharges to an existing draw.
NV
1 B 1
Form SW401 - LS -VFS - 29June2012 - Rev. 10 page 2 of 3

(If. ;OQUAEt? 1TEMM CHECKLIST.
EDIT 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.
Requried Item: Initials Page or plan sheet number and any notes:
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),
Forebay (if applicable),
High flow bypass system,
Maintenance access,
Proposed drainage easement and public right of way (ROW), and
Boundaries of drainage easement.
2. Plan details (1" = 30' or larger) for the level spreader showing:
- Forebay (if applicable),
High flow bypass system,
One foot topo lines between the level lip and top of stream bank,
Proposed drainage easement, and
Design at ultimate build -out.
3. Section view of the level spreader (1" = 20' or larger) showing:
- Underdrain system (if applicable),
Level lip,
Upslope channel, and
Downslope filter fabric.
4. Plan details of the flow splitting device and supporting calculations (if applicable).
5. A construction sequence that shows how the level spreader will be protected from
sediment until the entire drainage area is stabilized.
6. If a non - engineered VFS is being used, then provide a photograph of the VFS showing
that no draws are present.
7. The supporting calculations.
8. A copy of the signed and notarized operation and maintenance (0 &M) agreement.
Form SW401 - LS -VFS - 29June2012 - Rev.10 page 3 of 3

AVENUES II LEVEL SPREADER CALCULATIONS
DDV -13010
LEVEL SPREADER DESIGN
The purpose of the level spreader is to provide a non - erosive outlet by converting concentrated flow
into sheet flow and release it uniformly over the vegetated filter strip. The level spreader length
should be designed such that during the I "per hour storm event, a non - erosive velocity (in this case,
10 feet per cfs) is released from the level spreader into the vegetated filter strip.
Hydrology
Drainage Area to Level Spreader
Total Area = 9.64 ac
Impervious Area = 7.68 ac
Rational C Values
Impervious =
0.95
Open Space =
0.35
Rational Method Flow Calculation
C =
0.83
i =
1.00 in /hr
A =
9.64 ac
Q =
7.98 efs
Required Level Spreader Length = 10 LF per cfs
Min. Level Spreader Length = 79.8 feet
SPUTTER BOX DESIGN
The splitter box is designed such that the box provides sufficient driving head to pass the 1 "per hour
storm event though an orifice plate at the invert of the box without activating the bypass. Flows in
excess of the 1 "per hour storm will be bypassed.
Orifice Equation
Orifice Diameter = 18.00 in
Q =Cd *n *r'2 *V(
Cd =
r=
g=
Q=
Head from Centroid (h) =
Min. Bypass Pipe Invert Out =
2 *g *h)
0.6
0.750 ft
32.2 ft/s'
7.98 cfs
0.88 ft
243.89
J. SHINN, EI
7/7/2014

AVENUES iI LEVEL SPREADER CALCULATIONS J. SHINN, El
DDV -13010 Bvnass Channel 7/7/2014
LEVEL SPREADER DESIGN
Hydrology
Drainage Area to Level Spreader
Total Area = 9.64 ae
Impervious Area = 7.68 ac
Rational C Values
Impervious = 0.95
Open Space = 0.35
Rational Method Flow Calculation
C = 0.83
i = 7.24 in /hr (10 -year)
A = 9.64 ac
Q10 = 57.79 cfs

LEVEL SPREADER AND VEGErATED FILTER
IF4
CONSTRUCnON SPECIRCAMONS 5": po.
0
GENERAL NOTES
1. PRIOR TO CONSTRUCTION. ANY DISCREPANCIES IN THE PLANS AND NOTES SHALL BE BROUGHT TO THE DESIGN ENGINEER'S
ATTENTION IMMEDIATELY. TREE CONSERVATION
2. THE LEVEL SPREADER/ENGINEERED FILTER STRIP SYSTEM WILL BE REQUIRED TO BE CERTIFIED ONCE CONSTRUCTION IS SPUTTES 09- LINE (PPUOS)
COMPLETE. 36 0 RCP INV. IN = 243.99
36"0 RCP INV. OUT = 243.89
3. ALL CONSTRUCTION ACTIVITY RELATED TO THE PROPOSED FACILITIES SHALL BE PER THE DETAILS AND SPECIFICATIONS
SHOWN IN THESE DRAWINGS. SOILS, COMPACTION, AND OTHER MISCELLANEOUS DETAILS AND SPECIFICATIONS MAY BE 18"0 RCP INV. OUT 242.26
MODIFIED PER THE RECOMMENDATIONS OF THE ON-SITE GEOTECHNICAL ENGINEER. HOWEVER, PRIQR IQ IMELEMENI6139N, U� 0
THE DESIGN ENGINEER SHALL BE NOTIFIED OF ANY DEMA11ON FROM THESE DESIGN DRAWINGS, INCLUDING SHOP DRAWINGS
FOR ANY PROPOSED MODIFICATION. 51 LF 18"0 RCP 0 0.50%
/z 72 LF 36"0 RCP 0 2.6z'
4. THERE ARE EXISTING, JURISDIC11ONAL WETLANDS ON-SITE. PRIOR TO CONSTRUCTION, THESE AREAS SHALL BE STAKED AND
PROTECTED NTH TREE PROTECTION / SILT FENCE. UNDER NO CIRCUMSTANCES SHALL THERE BE ANY DISTURBANCE
BEYOND THE APPROVED WEILAND IMPACT AREAS DURING CONSTRUCTION. THE CONTRACTOR SHALL MONITOR THE WEILAND 36"0 RCP INV. 242.00
-SITE DOES NOT DISCHARGE INTO THESE AREAS. LL PER NCDOT STD. 838.80,
AREAS TO ENSURE SEDIMENT LADEN RUNOFF FROM DISTURBED AREAS ON ENDWA X
18"0 FES INV. 242.00
5. DURING AND AFTER CONSTRUCTION ACTIVITIES, ALL EXCAVATED MATERIALS SHALL BE REMOVED FROM THE SITE OR BYPASS CHANNEL TO BE UNED\
'/ / fl I I , ' I �11
LOCATED SUCH THAT RUNOFF FROM THESE MATERIALS (OR ANY OTHER DISTURBED AREA) DOES NOT ENTER THE WITH NCDOT CLASS T RIPRAP
JURISDICTIONAL WEILAND AREAS. 24" THICK, D50 13"
X
�k
6. ANY REMOVED TOPSOIL SHALL BE STOCKPILED FOR USE IN THE CONSTRUCTION OF THE ENGINEERED FILTER STRIP AT THE
FACILITY. PRIOR TO PLACEMENT OF THE 6" LAYER OF TOPSOIL IN THE ENGINEERED FILTER STRIP, THE CONTRACTOR SHALL X/ /x/
SCARIFY THE THE TOP 2"-3" OF EXISTING SOIL TO PROMOTE BONDING OF THE TOPSOIL WITH THE EXISTING SOIL.
C '4
7. IT IS AN11CIPATED THAT DEWATERING WILL BE NECESSARY IN THE EXCAVATION AREAS FOR THE FACILITIES. THEREFORE,
THE CONTRACTOR SHALL FURNISH, INSTALL, OPERATE, AND MAINTAIN ANY PUMPING EQUIPMENT, ETC.. NEEDED FOR
WITHIN THESE
REMOVAL OF WATER FROM VARIOUS PARTS OF THE LEVEL SPREADER SITES. DURING PLACEMENT OF FILL
AREAS, THE CONTRACTOR SHALL KEEP THE WATER LEVEL BELOW THE BOTTOM OF THE EXCAVATION / CONSTRUCTION
'n OTTOM AND SIDE
6 FT WIDE (1 FT DEEP) TRIANGULAR CHANNEL
AREAS. THE MANNER IN WHICH THE WATER IS REMOVED SHALL BE SUCH THAT THE EXCAVA ON B
SLOPES ARE STABLE, WITH NO SEDIMENT DISCHARGED FROM THE SITE (I.E. PUMPED WATER MAY NEED TO BE DIRECTED TO
N
"T;'
0 0.00% SLOPE LINED WITH CLASS 'B' RIPRAP
'4
AN APPROVED EROSION CONTROL DEVICE SUCH AS A DIRT BAG (ACF ENVIRONMENTAL), OR APPROVED EQUIVALENT, PRIOR
TO D
ISCHARGE).
VE AN 1,01-S"R
8. THE LEVEL SPREADER, AS PROPOSED ON THIS PROJECT, MUST BE LOCATED ON COMMON OPEN SPACE, HA
"gr
BERM SEPARATING BYPASS OUTFALL AND LEVE�Ll�
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SPREADER TO BE COVERED WITH RIPRAP
ACCESS AND MAINTENANCE EASEMENT LOCATED AROUND IT, AND INCLUDE AN OPERATIONS AND MAINTENANCE "Akjx
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MANUAL (O&M MANUAL) NTH A MAINTENANCE AGREEMENT. "A
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CONSTRUCTION SEQUENCE 30' VEGETATED FILTER
"'m"Z 1:31
'k,
TO BE SODDED
1 . THE OWNER SHALL OBTAIN A LAND DISTURB
NG (GRADING) PERMIT AND AN "APPROVAL TO CONSTRUCT' FROM THE CITY
RIVATE DRAINAGE EASEMENT
R
OF RALEIGH AND ALL OTHER APPLICABLE AGENCIES (I.E., 404 401 PERMITS, ST EAM BUFFER
100' SOLID MASONRY BLOCK LEV L
I L
SPREADER (SEE DErAIL)
TRUCTION. P
INTRUSIONS/MODIFICATIONS, FLOOD PLAIN DEVELOPMENT PERMITS ETC) PRIOR TO CONS LEVEL SPR
EADER UP ELEV.=242.00
EXISTING CHANNEL
T"�
X
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2. INSTALL ALL SEDIMENT AND EROSION CONTROL MEASURES PER THE APPROVED SEDIMENT AND EROSION CONTROL PLAN. THROUGH BUFFER u
\\W\\ r
THE EN11RE -,I Al'-."ll"
THE CONTRACTOR SHALL MAINTAIN ALL APPROVED SEDIMENT AND EROSION CONTROL MEASURES THROUGHOUT 3 FT WIDE LAYER OF #57 STONE ID XIC
PROJECT, AS REQUIRED. THE CONTRACTOR SHALL RECEIVE APPROVAL FROM THE EROSION CONTROL INSPECTOR, AS (4-INCHES DEEP) UNDERDRAIN'--
(SEE DET)
REQUIRED BY GOVERNING AGENCIES, PRIOR TO ANY CLEARING. WITH FILTER FABRIC
3. CLEAR AND GRUB AREA WITHIN THE LIMITS OF THE LEVEL SPREADER. ALL TREES AND THEIR ENTIRE ROOT SYSTEMS MUST
BE REMOVED FROM THE SWMF FOOTPRINT AREA AND BACK FILLED NTH SUITABLE SOIL MATERIAL. THE BACK FILLED
AREAS SHALL BE COMPACTED TO THE STANDARDS SET FORTH IN NOTE #4. PRIOR TO CONSTRUCTING THE LEVEL GRAPHIC SCALE
SPREADER STRUCTURE AND BYPASS BERM AT EACH SWMF, THE AREAS FOR THE ABOVE SHALL BE STRIPPED TO A 30 0 15 30 60
SUITABIF DEPTH AS DIRECTED BY THE ON-SITE GEOTECHNICAL ENGINEER. ANY RESIDUAL SOILS TO BE LEFT IN PLACE I I I
MUST BE WELL SCARIFIED TO PROMOTE BONDING NTH NEW COMPACTED FILL.
4. ALL FILL SOILS USED IN THE LEVEL SPREADER CONSTRUCTION SHALL BE COMPACTED TO AT LEAST 95% OF THE IdEVEL SPREADER #3 1 inch 30 ft.
STANDARD PROCTOR MAXIMUM DRY DENSITY (ASTM-698). THE FILL SOILS SHALL BE COMPACTED AT A MOISTURE 1" 30'
CONTENT WITHIN -1 TO +3 PERCENT OF ITS OPTIMUM MOISTURE CONTENT. COMPAC11ON TESTS SHALL BE PERFORMED BY
THE ON-SITE GEOTECHNICAL ENGINEER DURING CONSTRUCTION TO VERIFY THAT THE PROPER COMPACTION LEVEL HAS
BEEN REACHED. THE FILL SHOULD BE COMPACTED USING A SHEEPSFOOT TYPE COMPACTOR. IN ORDER TO PREVENT
DAMAGE TO THE PIPE, NO COMPAC11ON EQUIPMENT SHALL CROSS ANY PIPE UN11L MINIMUM COVER IS ESTABLISHED ALONG
THE PIPE.
5. THE ON-SITE GEOTECHNICAL ENGINEER SHALL INSPECT THE LEVEL SPREADER STRUCTURE SUBGRADE AND THE BYPASS
BERM SUBGRADE AT THE SWMF PRIOR TO PLACEMENT / COMPACTION OF ANY BACK FILL WITHIN THESE AREAS. IF THE
CONTRACTOR CONSTRUCTS AND COVERS UP THESE AREAS PRIOR TO INSPECTION, THEN THE SUBGRADE SHALL BE 'b. 0)
UNCOVERED AND TESTED AT THE CONTRACTOR'S EXPENSE. THE CONSTRUCTION OF THE LEVEL SPREADER STRUCTURE AND NOTES;
DIVERSION BERM AT THE SWMF SHALL NOT OCCUR UNTIL APPROVAL OF THE SUBGRADES IS OBTAINED FROM THE ON-SITE
r'7 -0 1. A FILTER BLANKET IS TO BE INSTALLED BETWEEN THE RIPRAP AND
GEOTECHNICAL ENGINEER. RIM EL. 254.00
7 SOIL FOUNDATION. THE FILTER BLANKET WILL CONSIST OF A MINIMUM
0
6. CONSTRUCT THE LEVEL SPREADER STRUCTURE, INSTALL THE FOREBAY AND BLIND CHANNEL UPSTREAM OF THE LEVEL 1 4- THICK LAYER OF STONE (NCDOT #57) UNDERLAIN NTH MIRAn
I � " - FILTER WEAVE 700 OR APPROVED EQUIVALENT
SPREADER STRUCTURE, INSTALL THE SPUTTER BOX, INSTALL THE BYPASS CHANNEL/BERM, AND THEN INSTALL THE
ENGINEERED FILTER STRIP DOWNSTREAM OF THE LEVEL SPREADER STRUCTURE AT THE SWMF. FOR THE FACILITY, IT IS
CONTRACTOR SHALL
RECOMMENDED THAT THE OUTLET FROM THE SPUTTER BOX TO THE LEVEL SPREADER STRUCTURE BE PLUGGED UNTIL THE SHAPE INVERT FOR CONTRACTOR SHALL PROVIDE
POSITIVE FLOW TO OUTLET
ENGINEERED FILTER STRIP HAS BEEN INSTALLED. ONCE A PRELIMINARY AS-BUILT OF THE CONSTRUCTED FACILITY IS STEPS IN ACCORDANCE WITH
VELOCITY DISSIPATOR
PROVIDED TO THE DESIGN ENGINEER AND IT HAS BEEN DETERMINED THAT THE SWMF HAS BEEN CONSTRUCTED IN NCDOT STD. 840.66. STEPS
NCDOT CLASS '1' RIPRAP
SH
24! L X 12.6' W X 24" THICK
GENERAL COMPLIANCE NTH THE PLANS AND SPECIFICATIONS FOR THE FACILITIES, THE DESIGN ENGINEER WILL NOTIFY THE ALL BE PLACED AT 16" O.C.
THE CONTRACTOR THAT THE PLUG CAN BE REMOVED. BASED ON THE RESULTS OF THE AS-BUILT SURVEYS, THE
ELEVATIONS FOR THE MASONRY BLOCKS MAY BE MODIFIED FROM THOSE PROVIDED IN THESE DRAWINGS. D50 13"
OUTLET STRUCTURE MATERIAL SPECIFICATIONS 11.74'
36" RCP (OUT),`.i"_ ENDWALL PER
1. THE 18"0 RCP OUTLET TO LEVEL SPREADER SHALL BE CLASS III RCP. INV. = 243.99 NCDOT STD. 838.80
(FROM DRAINAGE AREA)
2. THE CONCRETE FOR THE LEVEL SPREADER STRUCTURE SHALL BE MIN 3,000 PSI (28 DAY), SHALL INCLUDE 5-77.
ENTRAINED AIR, AND SHALL BE PLACED WITH A 3-5" SLUMP, UNLESS OTHERWISE INDICATED OR DIRECTED BY THE
DESIGN ENGINEER OR THE ONSITE GEOTECHNICAL ENGINEER. CONCRETE TESTING SHALL BE PROVIDED WITH THE AS-BUILT
36"0 O-RING RCP
RCP
CERTIFICATION TO ENSURE THAT THE ABOVE REQUIREMENTS HAVE BEEN ACHIEVED. (TO
ER)
EVEL SPREAD
TALLED WITH A Ll
3. ALL REINFORCING STEEL SHALL BE #4 CONFORMING TO ASTM A615, GRADE 60, AND SHALL BE INS
MINIMUM 3" CONCRETE COVER. 12.6'
4. THE REINFORCED CONCRETE FOOTER SHALL BE PLACED FIRST, FOLLOWED BY THE REINFORCED CONCRETE WALL. THE o
AL PART OF THE REINFORCED CONCRETE WALL X -0
REINFORCED CONCRETE CHEEK WALLS SHALL BE PLACED AS AN INTEGR >1`1 \36- RCP (OUT)
z 18" RCP
5. NOTE THAT NO CONCRETE SHALL BE PLACED WHEN THE AMBIENT AIR TEMPERATURES ARE EXPECTED TO BE ABOVE 857 z (OUT) INV. = 243.89
OR BELOW 407. CAST-IN-PLACE CONCRETE SHALL BE "WET CURED" AFTER FINISHING FOR A MINIMUM OF 48 HOURS. INV. = 242.26 (TO BYPASSCHANNEL)
STATEMENT OF RESPONSIBILITY ELAN MEW 5EQ110N MEW
1. ALL REQUIRED MAINTENANCE AND INSPECTIONS OF THE STORMWATER MANAGEMENT FACILITY SHALL BE THE RESPONSIBILITY
OF THE PROPERTY OWNER'S ASSOCIATION, PER THE EXECUTED OPERATION AND MAINTENANCE AGREEMENT FOR THIS FACILITY. _FWW-SPL=R SMUC11M - LLNEL SPIMMER
N.T.S.
PIAN
QENERAL
1. CONSTRUCT CONCRETE LEVEL SPREADER UP TO A ZERO PERCENT
LONGITUDINAL GRADE TO ENSURE UNIFORM SPREADING OF FLOW.
2. LEVEL SPREADER SHOULD BE CONSTRUCTED ON UNDISTURBED SOIL, AND
NOT ON FILL.
3. THE TRIANGULAR CHANNEL SHOULD BE CONSTRUCTED ON A ZERO
PERCENT GRADE.
3" SOLID MASONRY BLOCK UP ENDWALL PER
4. THE TRIANGULAR CHANNEL SHOULD BE LINED NTH CLASS 'B' RIPRAP. STUBBED ABOVE GRADE NCDOT STD, 838.80
5. THE 3-INCH LAYER OF #57 STONE SHALL BE UNDERLAIN NTH MIRAFI 3" SOLID MASONRY BLOCK (100' LENGTH AT ELEVATION 242-00)
FILTERWEAVE 400 OR ENGINEER APPROVED EQUIVALENT. LEVEL SPREADER
(100' LENGTH AT ELEVATION 242.00) CHANNEL SHALL BE LINED 36"0 O-RING RCP
3-FOOT WIDE LAYER OF #57 STONE NTH CLASS 'B' RIPRAP
(4--INCHES DEEP) UNDERLAIN WITH
30' VEGETATED FILTER FILTER FABRIC
TO BE SODDED TINUOUS
30' VEGETATED FILTER (3) #4 REBARS CON
TO BE SODDED W
6-FOOT WIDE (1-FOOT
DEEP) TRIANGULAR CHANNEL #4 REBAR 0 18- O.C. 2 LAYER OF CLASS "'I" RIP-RAP
Lk
3-FOOT WIDE LAYER OF 0 0.00% SLOPE LINED WITH 1 12" -4- FILTER BLANKET
CLASS 'B' RIPRAP
#57 STONE (4-INCHES 8.
TYP) 18" 1 8" (TYP) 12"
DEEP) UNDERLAIN NTH 3
FILTER FABRIC 3 8" FILTER BLANKET
AREA TO BE EXCAVATED AND -SOUD MASON BLOCK
(SEE NOTE)
FILLED WITH SELECT MATERIAL, 1-1 3- (TYP)
COMPACTED TO 95% MAX STD.
4P/'
PROCTOR DENSITY FORCED CONCRETE FOOTING 2
REIN
UNDISTURBED EARTH
2" DEE
REINFORCED CONCRETE FOOTING SOLID MASONRY BLOCK CONTINUOUS KEYWAY A-A
LEVEL 5EREADER !QRQSS-5EQ11!2bl FQOl]bIG DEIAIL
36" OUTLET BARREL VEIAXITY DISSIPATOR
.LEVEL SPREADER DETARS N.T.S.
N.T.S.
PRELIMINARY DRAWING - NOT RELEASED FOR CONSTRUCTION