20160512 Ver 1_Riparian Buffer Authorization_20160519

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May 19, 2016 �/
of Water Resources
1617 Mail Service Center
Raleigh, NC 27699-1617
20605'
Attn: Cherri Smith - 2
Re: Request for a Jordan Lake Buffer Authorization for the 751 South development site along NC 751 in
Durham County
Dear Ms. Smith:
On behalf of 751 South, Inc. (Client), VHB Engineering NC, P.C. requests a Jordan Lake Buffer
Authorization for the installation of two culverts and fill material needed to construct a road embankment.
Enclosed in this application is the DWR Riparian Buffer Authorization Form, VHB Authorization Form,
Stream Determination approval by Durham County (titled 751 Village Assemblage Project Surface Waters
Assessment), Level Spreader Design Summaries, Stormwater Management statement, Buffer Impact Sheet
and Grading and Drainage Plans.
The 751 South property is 74 acres and will be a mixed use development site. All streams, wetlands and
buffers have been avoided with the exception of this culvert location. This buffer site impacts 68 square
feet in Zone 1 and 2,329 square feet in Zone 2. All impacts are within allowable thresholds and no
mitigation is required.
Upon review, should you have any questions regarding the proposed project, please feel free to contact
me at 919-741-5543 or [e-mail]. We look forward to working with you through the permit
review process.
Sincerely,
Rachelle Beauregard
Senior Environmental Scientist
VHB Engineering NC, P.0
[e-mail]
CC: J. Alex Smith, 751 South Inc.
Preston Royster, Coulter Jewell Thames, PA
File 38210.02
D12COMC'
D
MAY 1 9 2016
DEQ -WATER RESOURCES
401 & BUFFER PERMITTING
Engineers I Scientists I Planners I Designers
4000 WestChase Boulevard
Suite 530
Raleigh, North Carolina 27607
P 919.829 0328
F 919 833.0034

DWR
State of North Carolina
Department of Environment and Natural Resources
Division of Water Resources Division of Water Resources
15A NCAC 02B.0233 (8)(b), .0243 (8)(b),.0250 (11)(b),.0259 (8)(b), .0267 (11)(c), .0607 (e)(2) — Buffer Authorization
FORM: BA 10-2013
Riparian Buffer Authorization Form
A. Applicant Information
1. Project Information
1 a. Name of project: 751 South
1 b. County: Durham
1 c. Nearest municipality: Durham
1 d. Subdivision name: N/A
1 e. Is the project located in any of North Carolina's
twenty coastal counties. If yes, answer 1f below.
❑Yes No
if. Is the project located within a NC Division of Coastal
Management Area of Environmental Concern (AEC)?
❑ Yes ❑ No
2. Owner Information
2a. Name on Recorded Deed:
751 South, Inc.
2b. Deed Book and Page No.
DB 5851 PG 59
2c. Map Book and Page No.
(include a copy of the recorded
map that indicates when the lot
was created:
N/A
2d. Responsible Party
(for Corporations):
J. Alex Mitchell
2e. Street address:
9310 NC Highway 751
2f. City, state, zip:
Durham, NC 27713
2g. Telephone no.:
919-206-4343
2h. Fax no.:
2i. Email address:
[e-mail]
3. Applicant Information (if different from owner)
3a. Applicant is:
® Agent ❑ Other, specify:
3b. Name.
3c. Business name
(if applicable):
3d. Street address:
3e. City, state, zip:
3f. Telephone no.:
3g. Fax no.:
3h. Email address:
FORM: BA 10-2013
D
I -AY 19 2016
DEQ -WATER RESOURCES
401 8 BUFFER PERMITTING
Page 1 of 7

r
Section A. Applicant Information, continued
4.
Agent/Consultant Information (if applicable)
4a.
Name:
Rachelle Beauregard
4b.
Business name
(if applicable):
VHB Engineering NC, P.C.
4c.
Street address:
4000 Westchase Blvd., Suite 530
4d. City, state, zip:
Raleigh, NC 27607
4e. Telephone no.:
919-741-5543
4f.
Fax no.:
919-833-0034
4g.
Email address:
[e-mail]
FORM: SSGP3080 8-13 Page 2 of 7

B. Project Information and Prior Project History
1. Property Identification
1 a. Property identification no (tax PIN or parcel ID):
PIN 0717-03-34-1812
1 b. Site coordinates (in decimal degrees):
Latitude: 35.876431
Longitude: -78.953672
1 c. Property size:
165 acres
2. Surface Waters
2a. Name of nearest body of water to proposed project:
New Hope Creek
2b. Water Quality Classification of nearest receiving
WS-IV, NSW
water:
2c. River basin:
Cape Fear
3. Project Description
3a. Describe the existing conditions on the site and the general land use in the vicinity of the project at the time of
this application:
The land use in the vicinity is mostly forested with some residential neighborhoods.
3b. Attach an 8'/2 x 11 excerpt from the most recent version of the USGS topographic map indicating the location
of the site See figure 3 from the 751 Village Assemblage Project Surface Waters Assessment document
3c. Attach an 8 1/2 x 11 excerpt from the most recent version of the published County NRCS Soil Survey Map
depicting the project site See figure 1 from the 751 Village Assemblage Project Surface Waters Assessment
document
3d. List the total estimated linear feet of all existing streams (intermittent and perennial) on the property-
1,981 feet (this includes the buffered streams)
3e. Explain the purpose of the proposed project:
The purpose of the project is to development the property as a mixed use project that includes residential,
commercial, retail, and office properties.
3f. Describe the overall project in detail, including the type of equipment to be used:
The overall project will develop the property into a mixed use development. Detention Basins and rip rap aprons
are used throughout the site. The only crossing with buffer impacts will include the installation of a 110 foot long,
54 inch culvert and fill material to construct the road embankment. The culvert will be buried approximately 10
inches to allow for aquatic passage. Headwalls will be installed at each end of the culvert to minimize the amount of
disturbance in the stream bed. The 18 inch pipe will be installed to fulfill one of the committed elements that was
part of the development plan approval and rezoning for the site that required an underpass for small to medium
sized wildlife. Additionally, a rip rap apron will be installed at the downstream end of the culver to slow discharge to
non-erosive velocities. The project and crossing will be constructed using typical heavy construction and earth
moving equipment including dozers, excavators, rollers, motor graders, and dump trucks. Typical earth moving and
heavy construction procedures will be used including mass grading, cut-fill operations, and fine grading.
4. Jurisdictional Determinations
4a. Have jurisdictional wetland or stream determinations by the
® Yes ❑ No ❑ Unknown
Corps or State been requested or obtained for this property/
project (including all prior phases) in the past?
4b. If yes, who delineated the jurisdictional areas?
Agency/ Consultant Company: S&EC
Name (if known): David Gainey
Other:
:l
4c. If yes, list the dates of the Corps jurisdictional determinations or State determinations and attach
documentation.
Durham County buffer calls made in 2007. The attached document from The Catena Group is the approval. A No
Practical Alternatives statement was approved by Durham County 2/8/16. The USACE made a site visit with S&EC
in 12/14, only S1 and S4 were determined to be jurisdictional. No documentation was given.
FORM: BA 10-2013 Page 3 of 7

B. Project Information and Prior Project History
5.
Project History
5a.
Have permits or certifications been requested or obtained for
this project (including all prior phases) in the past?
❑ Yes ® No ❑ Unknown
5b.
If yes, explain and detail according to "help file" instructions.
6.
Future Project Plans
6a.
Is this a phased project?
® Yes ❑ No
6b.
If yes, explain.
This buffer permit application covers the 751 development site itself. Road improvements along NC 751 for
this development are planned in the near future and those impacts may require a buffer permit.
FORM: SSGP3080 8-13 Page 4 of 7

EF
C. Proposed Impacts Inventory
1. Buffer Impacts
1 a. Project is in which protected
❑ Neuse ❑ Tar -Pamlico
❑ Catawba
basin?
❑ Randleman El Jordan ❑ Goose Creek
1 b. Individually list all buffer impacts below. If any impacts require mitigation, then you MIUST fill out Section D of
this form.
Buffer impact
Reason for
Type of impact
Stream name
Buffer
Zone 1
Zone 2
number —
impact
(exempt, allowable,
mitigation
impact
impact
Permanent(P)allowable
w/
mitigation)
required.
(sq ft)
(sq ft)
or Temporary
T
Stream S4 ® P
Road crossing of
Allowable
UT to New
❑ Yes ® No
68
1,193
❑ T
streams
Hope Creek
(Jordan Lake)
Stream S6 ® P
Road Crossing
Allowable
UT to New
❑ Yes ® No
0
1,136
❑ T
of Streams
Hope Creek
(Jordan Lake)
B3 ❑ P ❑ T
❑ Yes ❑ No
64 ❑ P ❑ T
❑ Yes ❑ No
65 ❑P El
El Yes [:]No
B6 ❑ P ❑ T
❑ Yes ❑ No
Total
buffer impacts
68
2,329
-1c. Comments:
D. Impact Justification and Mitigation
1. Avoidance and Minimization
1a. Specifically describe measures taken to avoid or minimize the proposed impacts in designing project.
The project as designed will avoid impacts to the only wetland on the property, all jurisdictional streams and almost
all impacts to buffers except for one unavoidable road crossing. The crossing was strategically located between
two streams. Both were determined to be subject to the Jordan Buffer Rules per Durham County in 2007.
Although, only the stream on the west side of the proposed road is jurisdictional (S4) per Eric Alsmeyer of the
USACE. Only buffer impacts are proposed for the road crossing. No stream or wetland impacts are proposed on
the entire site.
1 b. Specifically describe measures taken to avoid or minimize the proposed impacts through construction
techniques.
The proposed crossing will be constructed in the "dry" during low or no flow events. In the event that there is
flow in the channel, temporary dams and a pump around utilizing silt sacks will be used. The disturbed area will
be stabilized and revegetated as soon as possible following completion of the crossing.
FORM. BA 10-2013 Page 5 of 7

C. Impact Justification and Mitigation, continued
2. Buffer Mitigation
2a. Will the project result in an impact within a protected riparian buffer that requires buffer
mitigation?
❑ Yes ® No
2b. If yes, then identify the square feet of impact to each zone of the riparian buffer that requires mitigation and
calculate the amount of mitigation required in the table below.
Zone
Reason for impact Total impact Multiplier Required mitigation
(square feet (square feet
Zone 1
3 (2 for Catawba)
Zone 2
1.5
Total buffer mitigation required:
2c. If buffer mitigation is required, is payment to a
mitigation bank or NC EEP proposed?
❑ Yes ❑ No
2d. If yes, attach the acceptance letter from the mitigation bank or NC EEP.
2e. If no, then discuss what type of mitigation is proposed.
2f. Comments:
FORM: SSGP3080 8-13 Page 6 of 7

E. Diffuse Flow Plan
All buffer impacts and high ground impacts require diffuse flow or other form of
® Diffuse flow
stormwater treatment. Include a plan that fully documents how diffuse flow will be
® Other BMP
maintained. If a Level Spreader is proposed, attach a Level Spreader Supplement Form.
1 a.
If due to site constraints, a BMP other than a level spreader is proposed, please provide a
❑ Yes ® No
plan for stormwater treatment as outlined in Chapter 8 of the NC Stormwater BMP
of public (federal/state) land?
Manual and attach a BMP Supplement Form.
1 b.
F.
Supplementary Information
by First Class Mail via the US Postal Service:
1.
Environmental Documentation
OR NC DWR, Transportation Permitting Unit
1 a.
Does the project Involve an expenditure of public (federal/state/local) funds or the use
❑ Yes ® No
Raleigh, NC 27604
of public (federal/state) land?
For all other projects sent by delivery service
1 b.
If you answered "yes" to the above, does the project require preparation of an
❑ Yes ❑ No
OR Karen Higgins
environmental document pursuant to the requirements of the National or State (North
NCDWR — 401 & Buffer Permitting Unit
1617 Mail Service Center
Carolina) Environmental Policy Act (NEPA/SEPA)?
Raleigh, NC 27699 - 1617
1 c.
If you answered "yes" to the above, has the document been finalized by the State
❑ Yes ❑ No
Clearing House? (If so, attach a copy of the NEPA or SEPA final approval letter.)
Comments:
2.
Violations
2a.
Is the site in violation of DWR Wetland Rules (15A NCAC 02H 0500), Isolated Wetland
❑ Yes ® No
Rules (15A NCAC 02H .1300), DWR Surface Water or Wetland Standards, or Riparian
Buffer Rules (15A NCAC 02B .0200)?
2b.
Is this an after -the -fact permit application?
❑ Yes ® No
2c.
If you answered "yes" to one or both of the above questions, provide an explanation of the violation(s):
katehe le JgeRurey 4,1
Applicant/Agent's Printed Name
Applicant/Agent's Signature
(Agent's signature is valid only if an authorization letter from the applicant is provided )
Send this completed form and accompanying documents to the following:
S !�,
Date
For government transportation projects sent
For government transportation projects sent
by First Class Mail via the US Postal Service:
by delivery service (UPS, FedEx, etc.):
NC DWR, Transportation Permitting Unit
OR NC DWR, Transportation Permitting Unit
1617 Mail Service Center
512 N. Salisbury Street
Raleigh, NC 27699 --1617
Raleigh, NC 27604
For all other projects sent by First Class Mail
For all other projects sent by delivery service
via the US Postal Service
(UPS, FedEx, etc.):
Karen Higgins
OR Karen Higgins
NCDWR — 401 & Buffer Permitting Unit
NCDWR — 401 & Buffer Permitting Unit
1617 Mail Service Center
- 512 N. Salisbury Street
Raleigh, NC 27699 - 1617
Raleigh, NC 27604 y
FORM: BA 10-2013 Page 7 of 7

AGENT AUTHORIZATION FORM :.
Name: Southern Durham Development
Address: 9310 NC Highway 751, Durham, NC 27713
Phone: [phone]
Project Name/Description: 751 South
Mixed-use development along NC 751 in Durham County, includes permits for the development site
Itself and associated off-site roadway Improvements.
Date: March 28, 2016
US Army Corps of Engineers, Wilmington District
Raleigh Field Office
Attn: Eric Alsmeyer
3331 Heritage Trade Dr., Suite 105
Wake Forest, NC 28403
Re: Wetlands Related Consulting and Permitting
To Whom It May Concern:
I, the current applicant, hereby designate and authorize VHB Engineering NC, P.C. to act in my behalf
as my agent in the processing of permit applications, to furnish upon request supplemental information
in supportof applications, etc., from this dayforward. The 28 dayof March 2016.
This notification supersedes any previous correspondence concerning the agent for this project.
NOTICE: This authorization, for liability and professional courtesy reasons, is valid only for government
officials to enter the property when accompanied by VHB staff. You should call VHB to arrange a site
meeting prior to visiting the site.
—7r9 J c7A Tn,
Print Property Owner's Name
Property O er's Signature
cc• Cherri Smith cc: Rachelle Beauregard
DEQDWR VHB Engineering NC, P C
1628 Mail Service Center
Raleigh, NC 27699-1628
Englnoers Sclentis.s ?,wmcrq oagignors
P

751 Village Assemblage Project
Surface Waters Assessment
Durham County, North Carolina
TCG Job# 2124
Prepared for:
County of Durham Engineering Department
Joe Pearce
120 E. Parrish Street
Law Building, First Floor
Durham, NC 27701
Prepared by:
�,
Goter•O
114*61 Group
The Catena Group, Inc.
410-B Millstone Drive
Hillsborough, NC 27278
Tel [phone] Fax [phone]
December 2007
JAN 0 7 2000

751 Village Assemblage Project
December 2007
Surface Waters Assessment
Durham County, North Carolina
1.0 Purpose
� F-•
C:ibr ,
a•
The Catena Group (TCG) was contracted by Joe Pearce of the Durham County
Engineering Department to conduct an assessment of the surface waters on the 751
Village Project. The purpose of this investigation was to determine the locations and
extent of surface waters subject to protection under Section 404 of the Clean Water Act.
Additionally, this assessment was to determine the applicability of Durham County
stream buffer protection standards for the 751 Village Project. Durham County utilizes
stream buffer protection standards to preserve and maintain existing riparian zones for the
purposes of protecting water resources and improving water quality.
According to section 14-153(b) of the Durham County Ordinance, proposed
developments outside of the Neuse River Basin that are within the first 50 feet of a
surface water, i.e. intermittent or perennial stream, shall not be approved. Intermittent
and perennial streams are depicted on the most recent United States Geologic Survey
(USGS) 7.5 -minute topographic quadrangle map (Southwest Durham and Green Level
Quadrangles, 1981) and the United States Department of Agriculture (USDA) soil survey
of Durham County (1976). This ordinance had been amended by Durham County to
allow a review of surface waters depicted on the USGS topographic maps or the Durham
County soil survey that the applicant does not believe to accurately represent an
intermittent or perennial stream.
Twelve (12) intermittent streams are depicted on the project site in the Durham County
Soil Survey (Figure 1), including one (1) stream depicted in the USGS topographic map.
These surface waters were evaluated to assess the applicability of the Durham County
buffer protection standards. Personnel selected by the County Engineer can perform
delineations for these drainage features in an effort to determine whether the surface
waters identified on the maps are subject to buffer protection standards.
2.0 Project Description
The 751 Village project is located west of the Fayetteville Road (SR 1118) and NC 751
intersection, south of Stagecoach Road and east of Jordan Lake in Durham County, North
Carolina (Figure 2). This property is comprised of four parcels (PIN numbers 0717-03-
24-9899, 0717-03-44-1076, 0717-04-32-9923, and 0717-04-52-4401), totaling 164 acres.
751 Village ( December 2007
TCG Job#2124

7n_
3.0 Methodologies
TCG conducted the field investigations on Friday, December 7, and Monday, December
10, 2007. Streams and wetlands were evaluated to determine if they met the criteria for
jurisdictional status.
TCG was provided with an aerial photograph and parcel PIN numbers. Mapping
resources used in this investigation included the most recent USGS 7.5 -minute
topographic quadrangle map and the Durham County Soil Survey. The property PIN
numbers were reviewed on the Durham County Spatial Data Explorer web site
(http-//gisweb2.ci.durham.nc.us/sdo to determine the property boundaries. The property
boundary was overlaid onto a USGS topographic map and an aerial color infrared
orthophotography map (NCDOT 1998).
Jurisdictional delineations were performed using the three -parameter approach as
prescribed in the 1987 US Army Corps of Engineers (USACE) Wetlands Delineation
Manual (Environmental Laboratory 1987). Supplemental technical literature describing
the parameters of hydrophytic vegetation, hydric soils, and hydrological indicators was
also utilized.
Streams were evaluated according to the North Carolina Department of Water Quality
(NCDWQ) Identification Methods for the Origin of Intermittent and Perennial Streams
Version 3.1 (2005). This evaluation is based on three stream characteristics:
Geomorphology, Hydrology, and Biology. Generally, streams are determined to be
ephemeral, intermittent, or perennial based on 29 different attributes within these
characteristics by assigning a numeric score for each attribute. A stream reach with a
score of <19 is an ephemeral stream, a stream reach with a score of > 19 and < 30 is
intermittent, and a stream reach with a score of >_30 is perennial.
Jurisdictional streams and wetlands boundaries were marked in the field by flagging and
surveyed via satellite using a hand-held GPS unit (sub -meter accuracy).
4.0 Qualification of Investigators
The representative of TCG conducting this investigation was Jennifer Callahan. Mrs.
Callahan served as project manager with over five years of experience in the
environmental field. She has a B.S. degree in Environmental Resource Management and
a M.S. in Environmental Pollution Control from the Pennsylvania State University. Mrs.
Callahan is experienced with jurisdictional wetland and stream delineations,
environmental permitting, natural resource investigations, protected species surveys,
stream classifications and GPS surveys. Additionally, Mrs. Callahan has received
training in wetland delineation and the identification of intermittent and perennial
streams.
Assisting Mrs. Callahan during the field investigation was Kate Montieth of TCG. Ms.
Montieth is an Environmental Scientist with , 6 years experience in the environmental
751 Village 2 December 2007
TCG Job#2124

field. She has a B.A. degree in Biology from Reed College and a M.S. degree in
Environmental Sciences from the University of Rhode Island. Ms. Montieth has
experience in jurisdictional area delineations, stream and riparian buffer determinations,
protected species surveys, GIS mapping and analysis, as well as environmental document
and permit preparation.
5.0 Results
Eight (8) of the twelve (12) streams identified on the 751 Village property in the Durham
County Soil Survey were determined to be jurisdictional streams (S1, S2, S3, S4, S5, S6,
S7 and S8) (Figure 3). A DWQ stream form was completed for each of the jurisdictional
streams on the property (Appendix I). Table 1 describes each stream, including DWQ
classification and point score as well as location and drainage of the stream.
Table 1. Jurisdictional streams within the 751 Village Project.
Stream
DWQ Score
Classification
Location on Property
SI
21
Intermittent
Southern portion of property, drains to
floodplain / Jordan Lake
'S2
22
Intermittent
Southwestern portion of property (along
boundary), drains to floodplain / Jordan Lake
S3
22
Intermittent
Southwestern portion of property, drains to S2,
drains to floodplain / Jordan Lake
S4
20
Intermittent
Western, central portion of property, drains to
floodplain / Jordan Lake
S5
18.5*
Intermittent
Central portion of property, overland flow
drains to S4
S6
19.5
Intermittent
Ccntral portion of property, overland flow
drains to S4
S7
19.5
Intermittent
Northwestern portion of property, drains to
unnamed pond
S8
18.5*
Intermittent
Northeastern portion of property, drains to
floodplain / Jordan Lake
* Streams determined to be intermittent despite point score < 19. During normal rainfall year, streams
would likely score higher.
One (1) wetland was identified on the 751 Village Project during the field investigation.
Wetland I (WI) abuts the eastern side of S1 (Figure 3) and is approximately 0.0 16 acre.
This wetland is a depression that may have been manmade. The USACE routine wetland
determination forms for W 1 are included in Appendix II.
751 Village 3 December 2007
TCG Job#2124

fi
6.0 Summary
Approximately 0.016 acre of jurisdictional wetlands (WI) and approximately 2,195 linear
feet of jurisdictional streams (Sl, S2, S3, S4, S5, S6, S7 and S8) were delineated and
surveyed on the 751 Village Project by TCG. These wetlands and streams are regulated
by the USACE and NCDWQ under Sections 404 and 401 of the Clean Water Act,
respectively. This report is provided for preliminary planning purposes only and
represents TCG's professional opinion as to the jurisdictional status of the features on the
subject property. A jurisdictional determination will need to be approved by the
aforementioned regulatory agencies prior to obtaining permits to impact the jurisdictional
features. As a result of the findings of this investigation, it is TCG's opinion that the
eight (8) stream channels identified on the 751 Village Assemblage Project are
jurisdictional streams and are subject to the Durham County stream buffer protection
standards.
REFERENCES
Environmental Laboratory 1987. Corps of Engineers Wetlands Delineation Manual.
Technical Report Y-87-1. U.S. Army Engineer Waterways Experiment Station,
Vicksburg, MS. 100 pp.
NC Division of Water Quality (NCDWQ). 2005. Identification Methods for the Origins
of Intermittent and Perennial Streams. Version 3.1 North Carolina Department of
Environment and Natural Resources, Division of Water Quality. Raleigh, NC.
US Department of Agriculture (USDA). 1976. Soil Survey of Durham County, North
Carolina. US Department of Agriculture, Soil Conservation Service, and Forest
Service in Cooperation with NC Agricultural Experiment Station. 74 pp.
751 Village 4 December 2007
TCG Job#2124

FIGURES
Figure 1- Soil Survey
Figure 2 - Aerial Photograph
Figure 3 - Topographic Map with Jurisdictional Delineations
751 Village
TCG lob#2124
December 2007
N.

V '7
* � R
1 4
e, +
b
Ats
v'r
j vroperry boundary
250 500 Feet
i4.

Property Boundary
Streams
ya Wetland i ti
0 500 1,000 Feet'
y%`r. '•, -;sem �>..*.: ,1 r;' a° IL
,p
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Stream S77
5' �►
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. S2
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,'� Stream S3 wmp
The
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751 Village
Topographic Site Map
Jurisdictional Areas
Durham County, North Carolina
Date:
..JStream Si°
Figure
`Stream S1
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.lab No.:
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-
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t _
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.... �... �. �••���.� 1.. �. Y.T.
The
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751 Village
Topographic Site Map
Jurisdictional Areas
Durham County, North Carolina
Date:
Deren:hrr 2007
Figure
As Shown
.lab No.:
2124

City of Durham
Public Works Department
Stormwater Services Divisions
MY o MmicM 101 City Hall Plaza, Durham, North Carolina, 27701
Telephone [phone] FAX [phone]
Level Spreader" Design Summary
Stormwater Management Construction Plan Review:
A complete stormwater management construction plan submittal includes a design summary for
each stormwater BMP, design calculations, plans and specifications showing BMP, inlet and outlet
structure details.
1. PROJECT INFORMATION
Project Name: 751 SOUTH Phase 1
PIN: 0717-03-34-1812 Case #: D1500178
Design Contact Person: PRESTON ROYSTER Phone #: 919 682 - 0368
Legal Name of Owner:751 SOUTH INC
Owner Contact: J. ALEX MITCHELL Phone #:-
Owner Address: 9310 NC HIGHWAY 751, DURHAM, NC 27713
Deed Book 7855 Page # 175 or Plat Book 195 Page# 190 for BMP Property
For projects with multiple facilities, specify which facility this worksheet applies to: LS 7
*Water Quality Treatment: % TSS X Nitrogen X Phosphorous _ other
*Pollutant removal credits are achieved ONLY when the Vegetated Filter Strip (VFS) is an
engineered filter strip
Is there a BMP Upstream of the proposed Level Spreader?(ZD No
If yes, *Type of BMP WETPOND Drawdown Flow from the BMP 34 55 cfs
* Per the buffer rules, a level spreader is NOT needed down slope of a stormwater wetland,
bioretetention area or any other BMP that removes a minimum of 30% TN and 30% TP.
If No, Please provide below drainage area information:
Drainage area
Impervious area
Percent Impervious
Peak flow
Peak flow
ft2
ftZ
cfs (flow from 1 -inch per hour storm)
cfs (flow from 10 -year storm)
**When it appears that the location of a level spreader may be infeasible or inappropriate,
coordination with the Stormwater Services Division to discuss alternative solutions (i.e., the
provision of alternative water quality BMPs, etc.) shall be required.

or
"Please see Section 8.3 for information on Level Spreader design. Note that Preformed Scour
holes are NO longer allowed in lieu of LS. Where does the Level Spreader Discharge i.e. the type of
Vegetated Filter Strip (VFS)
X Engineered Filter Strip, _Riparian Buffer Z Where does the Level Spreader
Discharge i.e. the type of Vegetated Filter Strip
Slope within the VFS 3.33 %
'Max Average Slope cannot exceed 8%; a minimum level spreader length of at least 10 linear
feet shall be provided for each 1 cfs of design flow; the design flow entering the level spreader
cannot exceed 10 cfs; and
1 Max Average Slope cannot exceed S%; the design flow entering the level spreader (typically,
the 1 -inch per hour event) cannot exceed 2 cfs; a minimum level spreader length of at least SO
linear feet shall be provided for each 1 cfs of design flow.
Are there any naturally occurring channels downstream of the level spreader present? X Yes No
If yes, explain how sheet flow condition is sustained
SHEET FLOW FROM THE FILTER STRIP FLOWS PERPENDICULAR TO AND INTO
THE CHANNEL
Level Spreader design
Forebay Surface area
Design flow entering level spreader
Length of level Lip
Bypass channel length
Invert elevation of I -inch per hour (flow splitter)
Invert elevation of 1—inch per hour bypass
Peak velocity in the bypass channel
Reinforcement for bypass channel
II. REQUIRED ITEMS CHECKLIST
N/A
ft,
10.00
cfs
ion
ft
40
ft
XXX XX
ft
XXX XX
ft
XXX
ft/sec (10 -year event)
XXX
(provide calculations)
The following checklist outlines design requirements. Initial in the space provided to indicate the
following design requirements have been met and supporting documentation is attached.
Applicant's initials
PBR a. EIA description of the VFS characteristics downstream of the proposed level
spreader location has been provided.
PBR b. []Sizing of the level spreader (e.g., proposed length) based on design flow has
been provided.
PBR c.E,evel Spreader shall be concrete
PBR d.DA blind swale is required immediately upslope of the lip for stromwater
distribution. Blind swales shall be designed as 10 -ft wide linear wetlands and
shall be planted as such.
N/A e.DForebay has been provided with a surface area of 0.2% of the contributing
drainage area's impervious surface

PBR g.EEvaluation (i.e., discharge rates, erosive potential, etc.) of the high-flow bypass
channel has been provided.
PBR h.❑When an engineered filter strip is to be used, this strip shall be placed in an
easement and this filter strip area shall be maintained as a dense grass in
perpetuity. The design drawings should reflect this as well.
PBR i.❑A construction sequence that shows how the level spreaders will be protected
from sediment until the entire drainage area is stabilized is provided.
PBR j.❑Riprap outlet protection, if provided, reduces flow to non-erosive velocities.
PBR LOA recorded drainage easement is provided for each level spreader including
access to the nearest right-of-way and is graded per Section 8.3, Stormwater
Control Facilities (BMPs).
PBR 1.❑An annual operation and maintenance plan is provided.
PBR m.EA plan view of the level spreader system is provided.
PBR n. metails for the flow bypass structure are provided. Invert elevations are shown.
PBR o.❑A #57 stone is specified downstream of the level spreader.
PBR p.CRunoff from storms larger than the 1 -inch per hour storm is routed around the
level spreader,
Note: Executed Stormwater Facility Operation and Maintenance Permit Agreement,
payment of $700 permit fee per facility are required prior to construction drawing approval.

7 ■■amu.
City of Durham
Public Works Department
Stormwater Services Divisions
CRY o MMMEE 101 City Hall Plaza, Durham, North Carolina, 27701
Telephone [phone] FAX [phone]
Level Spreader" Design Summary
Stormwater Management Construction Plan Review:
A complete stormwater management construction plan submittal includes a design summary for
each stormwater BMP, design calculations, plans and specifications showing BMP, inlet and outlet
structure details.
I. PROJECT INFORMATION
Project Name: 751 SOUTH
Phase 1
PIN: 0717-03-32-4970 Case #: D1500178
Design Contact Person: PRESTON ROYSTER Phone #: 919 682 - 0368
Legal Name of Owner:SOUTHERN DURHAM DEVELOPMENT LLC
Owner Contact: J. ALEX MITCHELL
Phone #:
Owner Address: 9310 NC HIGHWAY 751, DURHAM, NC 27713
Deed Book 6651 Page # 916 or Plat Book 195 Page# 190 for BMP Property
For projects with multiple facilities, specify which facility this worksheet applies to: LS 3
*Water Quality Treatment: _ %'TSS X Nitrogen X Phosphorous _ other
*Pollutant removal credits are achieved ONLY when the Vegetated Filter Strip (VFS) is an
engineered filter strip
Is there a BMP Upstream of the proposed Level Spreader?<ZD No
If yes, *Type of BMP WETPOND Drawdown Flow from the BMP 6.01 cfs
* Per the buffer rules, a level spreader is NOT needed down slope of a stormwater wetland,
bioretetention area or any other BMP that removes a minimum of 30% TN and 30% TP.
If No, Please provide below drainage area information:
Drainage area ftZ.
Impervious area ftZ
Percent Impervious %
Peak flow cfs (flow from I -inch per hour storm)
Peak flow cfs (flow from 10 -year storm)
**When it appears that the location of a level spreader may be infeasible or inappropriate,
coordination with the Stormwater Services Division to discuss alternative solutions (i.e., the
provision of alternative water quality BMPs, etc.) shall be required.

"Please see Section 8.3 for information on Level Spreader design. Note that Preformed Scour
holes are NO longer allowed in lieu of LS.Where does the Level Spreader Discharge i.e. the type of
Vegetated Filter Strip (VFS)
X Engineered Filter Strip, _Riparian Buffer 2 Where does the Level Spreader
Discharge i.e. the type of Vegetated Filter Strip
Slope within the VFS 8.00 %
'Max Average Slope cannot exceed 8% ; a minimum level spreader length of at least 10 linear
feet shall be provided for each 1 cfs of design flow; the design flow entering the level spreader
cannot exceed 10 cfs; and
2 Max Average Slope cannot exceed 5%; the design flow entering the level spreader (typically,
the 1 -inch per hour event) cannot exceed 2 cfs; a minimum level spreader length of at least SO
linear feet shall be provided for each 1 cfs of design flow.
Are there any naturally occurring channels downstream of the level spreader present? X Yes No
If yes, explain how sheet flow condition is sustained
SHEET FLOW FROM THE FILTER STRIP FLOWS PERPENDICULAR TO AND INTO
THE CHANNEL
Level Spreader design
Forebay Surface area
Design flow entering level spreader
Length of level Lip
Bypass channel length
Invert elevation of 1 -inch per hour (flow splitter)
Invert elevation of l—inch per hour bypass
Peak velocity in the bypass channel
Reinforcement for bypass channel
II. REQUIRED ITEMS CHECKLIST
N/A ft,
6.01. cfs
65 ft
N/A ft
XXX XX ft
XXX.XX ft
N/A ft/sec (10 -year event)
N/A (provide calculations)
The following checklist outlines design requirements. Initial in the space provided to indicate the
following design requirements have been met and supporting documentation is attached.
Applicant's initials
PBR a. 0A description of the VFS characteristics downstream of the proposed level
spreader location has been provided.
PBR b.i Sizing of the level spreader (e.g., proposed length) based on design flow has
been provided.
PBR c.El,evel Spreader shall be concrete
PBR d. 0A blind swale is required immediately upslope of the lip for stromwater
distribution. Blind swales shall be designed as 10 -ft wide linear wetlands and
shall be planted as such.
N/A e.EForebay has been provided with a surface area of 0.2% of the contributing
drainage area's impervious surface

Note: Executed Stormwater Facility Operation and Maintenance Permit Agreement,
payment of $700 permit fee per facility are required prior to construction drawing approval.
f. ❑ `,
N/A
g.i Evaluation (i.e., discharge rates, erosive potential, etc.) of the high-flow bypass
channel has been provided. 11
PBR
h.❑When an engineered filter strip is to be used, this strip shall be placed in an
easement and this filter strip area shall be maintained as a dense grass in
perpetuity. The design drawings should reflect this as well.
PBR
i.❑A construction sequence that shows how the level spreaders will be protected
from sediment until the entire drainage area is stabilized is provided.
PBR
j.❑Riprap outlet protection, if provided, reduces flow to non-erosive velocities.
PBR
k.❑A recorded drainage easement is provided for each level spreader including
access to the nearest right-of-way and is graded per Section 8.3, Stormwater
Control Facilities (BMPs).
PBR
I.❑An annual operation and maintenance plan is provided.
pBR m. [A plan view of the level spreader system is provided.
PBR
n.EDetails for the flow bypass structure are provided. Invert elevations are shown.
PBR
o.❑A #57 stone is specified downstream of the level spreader.
PBR
p.ERunoff from storms larger than the 1 -inch per hour storm is routed around the
level spreader,
Note: Executed Stormwater Facility Operation and Maintenance Permit Agreement,
payment of $700 permit fee per facility are required prior to construction drawing approval.

751 South Stormwater Management
In order to control stormwater runoff from the site, curb and gutter and storm drain piping will be
installed to direct runoff to points of discharge. In order to meet the local stormwater requirements
(85% TSS removal, nitrogen and phosphorus reduction, and peak flow attenuation), runoff from all
impervious surface on the site will be routed to wet detention ponds. The ponds will provide total
suspended solids removal, nutrient reduction, and peak flow attenuation for runoff prior to being
discharged to the downstream receiving waters. Level spreaders are proposed at the outlets of two of
the ponds. The level spreaders will provide diffuse flow of the pond discharge prior to entering the
stream buffers while also providing additional nutrient reduction (ponds with level spreaders are
clouded in green in the attached drawing and those without level spreaders are clouded in red). For the
pond adjacent to the wetland on the south end of the site, discharge from the pond will be split in the
outlet structure. So, the 10 -yr storm discharge will be directed to the level spreader while larger storms
are bypassed and will discharge into the wetland. For the level spreader in the northwest corner of the
site, the flow will be split at the outlet. Again, the 10 -yr discharge will be directed to the level spreader
while larger storms will bypass via a bypass channel. Rip rap velocity dissipator pads will be provided at
the outlets of the other three ponds on the site. These will be designed to reduce the flow from the
pipes to non-erosive velocities while providing some diffuse flow.

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