20120779 Ver 1_Stormwater Info_20120907

ENVIRONMENTAL SERVICES, INC.
524 S. NEW HOPE ROAD
RALEIGH. NORTH CAROLINA 27610
919 - 212 -1760 • FAX 919 - 212 -1707
www.enviromnentalservicesinc.com
September 5, 2012
Ms. Annette Lucas, P.E.
N.C. Division of Water Quality
1650 Mail Service Center
Raleigh, NC 27699 -1650
Re: DWQ #2012 -0779; 55 James at Midtown
Apex, NC
Ms. Lucas:
° @EAR o
SEP - 7 2012
DENR - WATER dUVITY
ESI is submitting the enclosed diffuse flow plan for the project, 55 James at Midtown, on
behalf of the applicant JVI Construction. The project engineer is Mr. Peter Cnossen, P.E. of
Jones & Cnossen Engineering, PLLC.
Lauren Witherspoon has informed me that she has reviewed the remaining portions of the
Section 401 application and that this diffuse flow plan was the last item required. Please let
us know if you have any questions or comments.
Sincerely,
Environmental Services, Inc.
eff Harbour, PWS
Senior Manager
Enclosure: Diffuse flow plan and worksheets
Cc: Peter Cnossen, P.E.
FLORIDA • GEORGIA • NORTH CAROLINA • SOUTH CAROLINA • MARYLAND • OHIO

A
HWEHR
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, initiated, and submitted
Project name
Contact name
Phone number
Date
Drainage area number
The purpose of the LS-VFS
Stormwater enters LS-vFS from
Type at VFS
Explanation of any 'Other' responses above
N Stormwater Enters the LS-VFS from the Drainage Area
Drainage area
impervious surface area
Percent Impervious
Rational C coefficient
Peak flow from the 1 irubr storm
Time of concentration
Rainfall intensity, 10-yr Storm
Peak flow from the 10-yr storm
Design storm
Maximum amount of flow directed to the LS-VFS
Is a low bypass system going to be used?
Explanation of arty 'Other- responses above
I Stormwater Enters the LS•VFS from a BMP
Type of BMP
Peak discharge from the BMP during the design storm
Peak disdtarge from the BMP during the 10-year storm
Maximum capacity of a 100 -foot long LS-VFS
Peak flow directed to the LS-VFS
Is a flow bypass system going to be used?
Explanation of any 'Other responses above
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Form SW401 - LS-VFS - 29June2012 - Rev. 10 page 1 of 3

LS-VFS Design
Forebay surface area
Depth of frebay at stormwater entry point
Depth of forebay at stomnxathr exit pant
Feet of level lip needed per cis
Computed minimum length of the level rip 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 I" rip to the end of the VFS)
Are any draws print In the VFS?
Is More a collector swale at the end of the VFS?
Bypass System Design (if applicable)
Is a bypass system provided?
Is there an engineered flax spffing 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 veto* 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
M
sq ft
No faebay is required.
Depth is awopnata.
50* fticfs
5 ft
Ten feet Is the minimum level spreader length.
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Form SW401- LS-VFS - Mune2012 - Rev. 10 page 2 of 3
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Form SW401- LS-VFS - Mune2012 - Rev. 10 page 2 of 3

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.
Requded Item:
1. Plans (I'- 50' or larger) of the entire site showing:
- Design at ultimate build -out,
- Off -site drainage (d applicable),
- Defsleated 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 tip and top of stream bank
- Proposed drainage easemerd, and
Design at ultimate build -out
3. Section view of the level spreader (1'= 20' or larger) showing:
- Underdrain system (r7 applicable),
- Level tip,
- Upslope channel, and
- Downslope filter fabric.
4. Plan details of the low splitting device and supporting calculations (f applicable).
5. A construction sequence that shows how the level spreader will be protected from
sediment until the entire drainage area Is stabif¢ed.
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 - Mune2012 - Rev.10 page 3 of 3

W�
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~ \ ! \ E
N-50,
v
EMERGENCY
\ \ \ \ / / \' / / \\ \ . �, '• TO \ SPILLWAY
\ \� / / ! / 432\ • \•
094 F( \
R11-`RAP \
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/81RCp FOREBAY \ /
i
it \V_ LEVEL SPREADER
v
/ CB# 2 �y �\ I //p Q / / '/ / / 15" FES 6' L
Q \/ 3 1 A O 0� I /' / / , INV. = 429.4
/ M h
\ \ \ ~ °® \-s / •� / BMP MAINTENANCE -
/ i / \ `� .,,.. ",�•'r / // AND ACCESS
EASEMENT
if`
ol-
r ,
TRASH RACK
4' WIDE TOP OF DAM = 43G.5
COIR POROUS 100 -YEAR FLOOD ELEV. EMERGENCY SPILLWAY
BAFFLES (3) = 435.G7 ELEV. = 435.G7
WATER QUALITY STORAGE A PRIMARY SPILLWAY ELEV.
TOP OF RISER = 435.57 - = 435.57
?� VEGETATIVE 2" DIAM. POND
SHELF (TYP) DAM
NORMAL POOL ELEV. = 434.1 DRAIN PIPE
SPILLWAY -
W N
FOREBAY R
VALVE -'"' 24'1
CONTRACTOR TO WRENCH W! RI5EP
INSTALL 2 -112" \ BRACKET
SKIMMER FOR TEMP.
SEDIMENT CONTROL
C�tn V _
r. ' . Tom-- G" DRAIN
W! VALVE \
NOTES:
1. RI5EK SHALL BE 24" x 24" (INTERIOR)
PRECAST STRUCTURE.
2. POND BOTTOM ELEVATION 15 427 AND
BOTTOM OF SEDIMENT AREA 15 42G.
3. POND WILL HAVE MINIMUM G" CLAY LINER
21, 5" BARREL
1' SEDIMENT
ACCUMULATION
F
OF THESE CONSTRUCTION PLAN5.
AREA 12"
s. F
Cid
4'x4x2'
DATE
4'x4'x 1'
DEEP
PUBLIC WORKS - ENV. PROGRAMS
CONC.
CONC,
z
ANTI -SEEP
FOOTING
DATE
COLLAR
DETAIL - FOND
2
N.T.5.
CM - BUILDING INSPECTIONS
DATE
NOTES:
I . ALL MATERIALS AND METHODS OF CONSTRUCTION SHALL BE IN ACCORDANCE WITH TOWN OF APEX
STANDARDS AND SPECIFICATIONS.
2. BOUNDARY AND TOPOGRAPHIC INFORMATION TAKEN FROM SURVEY PROVIDED BY SMITH *SMITH
SURVEY COMPANY.
3. CONTRACTOR SHALL HAVE NORTH CAROLINA ONE CALL (I - 800 -G32 -4949) LOCATE ALL EXISTING
UTILITIES PRIOR TO BEGINNING CONSTRUCTION.
4. CONTRACTOR SHALL INSTALL ALL EROSION CONTROL DEVICES IN THE BEST LOCATION BASED UPON FIELD
CONDITIONS.
G. THE RIP -RAP APRON ON THE FOREBAY DAM SHOULD BE 5" LOWER THAN THE REST OF THE FOREBAY DAM.
MINIMUM
DEPTH= 12"
INV. =
429.3
RIP -RAP
D50 =G"
kQ �l BOTTOM WIDTH = 5'
GEOTEXTILE LINER
RIP -RAP
APRON
EMERGENCY SPILLWAY DETAIL
N.T.5.
TOP OF
DAM
MIN
STRUCTURAL BMP CONSTRUCTION SEQUENCE:
THE FOLLOWING MUST OCCUR PRIOR TO FINAL PLAT AND /OR CERTIFICATE OF OCCUPANCY (CO):
I . ALL STRUCTURAL BMP5 MUST BE INSTALLED IN ACCORDANCE WITH THE APPROVED CONSTRUCTION DRAWINGS.
2. THE DESIGN ENGINEER MUST SUBMIT AN AS -BUILT PACKAGE WHICH MEETS ALL REQUIREMENTS PRESENTED IN THE
TOWN SPEC BOOK INCLUDING A SIGNED AND SEALED CERTIFICATION STATEMENT,
3. SUBMIT THE APPROPRIATE SIGNED STRUCTURAL BMP Q *M AGREEMENT AND NIIAINTENANCE GUARANTEE TO THE
DEVELOPMENT PROJECTS COORDINATOR IN CONSTRUCTION MANAGEMENT AT 249 -3394.
4. A FINAL INSPECTION BY THE ENVIRONMENTAL PROGRAMS MANAGER SHALL BE CONDUCTED ONCE THE A5 -BUILT
SUBMITTAL HAS BEEN RECEIVED. ONCE APPROVED, THE ENVIRONMENTAL PROGRAMS MANAGER WILL SEND A BMP
APPROVAL LETTER TO THE OWNER.
5. IN LIEU OF STRUCTURAL BMP COMPLETION AND FINAL APPROVAL BY THE ENVIRONMENTAL PROGRAMS MANAGER,
THE TOWN MAY ACCEPT A PERFORMANCE GUARANTEE IN ACCORDANCE WITH U'DO SECTION G. 1. 12(G). IF THE
CONTRIBUTING DRAINAGE AREA FOR THE BMP5 IS UNSTABLE AT THE TIME OF 1 INAL PLAT APPROVAL FOR A
SUBDIVISION, THE TOWN WILL ALLOW A SKIMMER SYSTEM TO BE CONNECTED TO THE EMERGENCY DRAIN 512ED TO
DE -WATER THE VOLUME OF THE BASIN OVER A 2 -3 DAY PERIOD. POROUS BAFFLES SHALL EITHER CONTINUE TO BE
MAINTAINED (IF CONVERTING FROM A SEDIMENT BASIN) OR BE INSTALLED. ANY ORIFICES MUST BE CAPPED OR
PLUGGED.
6. ALL STRUCTURAL BMP5 ARE REQUIRED TO BE COMPLETED PRIOR TO A FINAL GO FOR A SITE PLAN AND 155UANCE OF
90% OF C05 WITHIN A SUBDIVISION. IF THE SUBDIVISION IS TO BE PHASED, ALL STRUCTURAL BMP5 SHALL BE
COMPLETED PRIOR TO ISSUANCE OF 90% OF COS WITHIN THAT PHASE.
7. IF A STRUCTURAL BMP COUNTS TOWARDS RCA, THE REQUIRED LANDSCAPING SHALL BE INSTALLED DURING THE
APPROPRIATE GROWING SEASON AND COORDINATED WITH THE TOWN ZONING COMPLIANCE OFFICER AT 249 -342G.
TOWN REQUIRED SUBDIVISION NOTES:
I . NO SITE DEVELOPMENT ACTIVITY INCLUDING BUT NOT LIMITED TO TESTING CLEARING, INSTALLATION
OF 5 *E MEASURES, OR GRADING, SHALL OCCUR UNTIL REQUIRED PROTECTION FENCING HAS BEEN
INSTALLED AND INSPECTED. A PROTECTION FENCING INSTALLATION PERMIT MAY BE OBTAINED AT THE
PLANNING DEPARTMENT OR BY CALLING 9 13 249 -3426.
2. PROTECTION FENCING MUST BE PLACED AWAY FROM ANY SAVED TREE ONE FOOT FOR EACH INCH OF
TREE CALIPER. PROTECTION FENCING MUST BE PLACED AT LEAST 10 FEET AWAY FROM ANY OTHER
DESIGNATED RESOURCE CONSERVATION AREA, SUCH AS BUT NOT LIMITED TO HISTORIC BUILDINGS
AND STRUCTURES, WETLANDS, AND PONDS. PROTECTION FENCING MUST BE PLACED ALONG THE
OUTSIDE LINE OF THE 100 -YEAR PLOODPLAIN, AND THE OUTSIDE EDGE OF AN.0( RIPARIAN BUFFER.
ADDITIONAL PROTECTION FENCING MAY BE REQUIRED IN OTHER LOCATIONS CLOSE TO
CONSTRUCTION ACTIVITY WHERE IT IS DEEMED NECESSARY BY THE ZONING ENFORCEMENT OFFICER;
SUCH AREAS MAY INCLUDE BUT ARE NOT LIMITED TO COMMON PROPERTY LII'E5 OR NEAR PUBLIC
AREAS (SIDEWALKS, ETC.).
3. ALL GRADING AND SUPPORT STRUCTURES A550CIATED WITH ANY RETAINING STRUCTURE SHALL NOT
ENCROACH INTO ANY REQUIRED BUFFER OR PROTECTED AREA (SUCH AS BUT NOT LIMITED TO, RCA
AND CRITICAL ROOT ZONES OF TREES, PUBLIC UTILITY EASEMENTS AND RIGHTS -OF -WAY), AND SHALL
BE CONTAINED ENTIRELY ON SITE.
4, SITE ELEMENTS REQUIRED TO SATISFY RECREATIONAL REQUIREMENTS SUCH AS BUT NOT LIMITED TO
PLAY FIELDS AND GREENWAY TRAILS AND ITEMS TYPICALLY ASSOCIATED WITH THEM (BENCHES, TRASH
CONTAINERS, SIGNS, ETC.) MUST MEET ANY APPLICABLE STANDARDS FOUND IN THE TOWN OF APEX
STANDARD SPECIFICATIONS AND CONSTRUCTION DETAILS AND THE REQUIR5MENT5 OF THE TOWN OF
APEX PARKS AND RECREATION DEPARTMENT.
5. RETAINING SYSTEMS PROVIDING A CUMULATIVE VERTICAL RELIEF GREATER THAN FIVE FEET IN HEIGHT
WITHIN A HORIZONTAL D15TANCE OF 50 FEET OR LESS, INCLUDING RETAINING WALLS OR
MECHANICALLY STABILIZED EARTH WALLS SHALL BE DESIGNED AND CONSTRUCTED UNDER THE
RESPONSIBLE CHARGE OF A REGISTERED PROFESSIONAL ENGINEER AND CON4PLY IN ALL ASPECTS
WITH THE NC BUILDING CODE SECTION I G 10. RETAINING SYSTEMS MEETING TH15 CRITERIA WILL
REQUIRE A SEPARATE BUILDING PERMIT PRIOR TO START OF WORK.
Figure 8-3:
Profile V,lew Of a LS --1v'F5 -vith aigineesed Filter Strip Iffioin Winston and Hi'mt 2,0 10),
6 ft t ft 3 ft 30 or 5a ft
- Level .Spreader
NOTES:
1. FABRICATE TRASH RACK BY
WELDING #4 REBAR SPACED 8"
ON CENTER
2. BOLT BOTTOM OF TRASH
RACK TO TOP OF 24 "1 R15ER
24"
D ETA I L- T INAS h I` AC K
Underdra
(opliona
Appropriately Sized
Footer
Vegetative Filter Strip
Stolle
Figure 8-8:
Schematic of a Forebay for Use with a Le-vel Spreader {Hathaway, and Hxuit 2006)
S ' d 2011
THE SIGNATURES AFFIXED BELOW CERTIFY THAT THIS SHEET HAS BEEN REVIEWED AND APPROVED 50LELY
PER THE CERTIFICATIONS SIGNED ON
THE COVER SHEET
OF THESE CONSTRUCTION PLAN5.
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221 N. SALEM ST.
SUITE 001
PO BOX 1062
APEx, NC 27502
Office: 919 -387 -1174
Registration: P-0151
www.jormwmosm.com
DATE
AUGUST G, 2012
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