SW8950204_CURRENT PERMIT_20200603

STORMWATER DIVISION CODING SHEET
POST -CONSTRUCTION PERMITS
PERMIT NO.
SW8 9s0o�'
DOC TYPE
[] CURRENT PERMIT
❑ APPROVED PLANS
❑ HISTORICAL FILE
❑ COMPLIANCE EVALUATION INSPECTION
DOC DATE
aV O 0 (b 0 3
YYYYMMDD

ROY COOPER
Govemor
MICHAEL S. REGAN
secretary
BRIAN WRENN
Acting Direcwr
June 3, 2020
New Hanover County
Attn: Tim Burgess, County Manager
230 Government Center Drive, Suite 195
Wilmington, NC 28403
NORTH CAROUNA
Enrlrunmentnl Quality
Subject: Approved Minor Modification
Stormwater Permit No. SW8 950204
Castle Hayne Park
New Hanover County
Dear Mr. Burgess:
On March 4, 2020, the Wilmington Regional Office of the Division of Energy, Mineral and Land
Resources received and accepted a complete minor modification application for changes to the approved
plans for Stormwater Management Permit Number SW8 950204. It has been determined that the nature
of the proposed change meets the definition of a minor modification in that it does not result in an
increase in the size of the permitted stormwater control measure (SCM) and does not increase the amount
of built -upon area. Please refer to Attachment C for a detailed description of the current proposed minor
modification and a list of all the past modifications approved during the effective period of the permit.
We are forwarding you an approved copy of the modified plans for your files. Please add the attached
plans to the previously approved plan set. Please replace the previously issued permit with the revised
permit, dated June 3, 2020, attached. This revised permit does not impose new or different terms; it
merely restates some of the previous terms to provide you with a better understanding of your obligations
under the permit.
Please be aware that all terms and conditions of the permit issued on June 3, 2020 and modified as
attached, remain in full force and effect. Please also understand that the approval of this minor
modification to the subject State Stormwater Permit is done on a case -by -case basis. Any other changes
to this project must be approved through this Office prior to construction. The approval of this mirror
modification does not preclude the permittee from complying with all other applicable statutes, rules,
regulations or ordinances which may have jurisdiction over the proposed activity, and obtaining a permit
or approval prior to construction.
If you have any questions concerning this matter, please contact Ted Triantis in the Wilmington Regional
Office at [phone] or [e-mail].
Sincerely, J
• j / J�w
,.Brian Wrenn, Acting Director
Division of Energy, Mineral and Land Resources
Enclosures: Attachment C — Permitting History
Application Documents
DESliju %StormwaterTermits & Projects\ 1995\950204 LD12020 05 permit —minor 950204
cc: Jeffrey B. Petroff, P.E., Coastal Land Design, PLLC: email: [e-mail]
New Hanover County Building Safety Department
Wilmington Regional Office Stormwater File
® — �� North Carolina Department of Environmental Quality I Division of Energy. Mineral and Land Resources
Wilmington Regional Office 1 127 Cardinal Drive Extension I Wilmington. North Carolina 28405
rioasN cwounu�
°+��a 910.796.7215

State Stormwater Management Systems
Permit No. SW8 950204
������]yaf]:i9:[*7-A:Z9111I;T_•1
DEPARTMENT OF ENVIRONMENTAL QAULITY
DIVISION OF ENERGY, MINERAL AND LAND RESOURCES
STATE STORMWATER MANAGEMENT PERMIT
In accordance with the provisions of Article 21 of Chapter 143, General Statutes of North
Carolina as amended, and other applicable Laws, Rules and Regulations
PERMISSION IS HEREBY GRANTED TO
New Hanover County
Castle Hayne Park
4700 Old Avenue, Castle Hayne, New Hanover County
FOR THE
construction, operation and maintenance of a combined low density development, 30% for
the 54.09 acre tract and 24% for the 45.42 acre tract, in compliance with the minor
modification provisions of Session Law 2008-211 and Title 15A NCAC 2H .1000 (hereafter
referred to singly and collectively as the "stormwater rules') and the approved stormwater
management plans and specifications, and other supporting data as attached and on file with
and approved by the Division of Energy, Mineral and Land Resources and considered an
enforceable part of this permit.
The Permit shall be effective from the date of issuance until rescinded and shall be subject to
the following specific conditions and limitations:
This permit covers the construction of a total of 1,181,683 square feet of built -upon
area, which includes 109,662 square feet of proposed BUA, 862,234 square feet of
future BUA allocation and 209,787 square feet of existing/previously permitted BUA.
2. The overall tract built -upon area percentage for the project must be maintained at no
more than 27.26%, as required by the stormwater rules. This is a weighted value
based on 30% of the 54.09 acre tract and 24% of the 45.42 acre tract.
3. The only runoff conveyance systems allowed will be vegetated conveyances such as
swales with minimum side slopes of 3:1 (H:V) as defined in the stormwater rules and
approved by the Division.
4. Projects covered by this permit shall maintain a vegetated buffer adjacent to surface
waters, measured horizontally from and perpendicular to the normal pool of
impounded structures, the top of bank of each side of streams and rivers, and the
mean high water line of tidal waters. Within the 54.09 acre project area, the minimum
buffer width shall be 30 feet. Within the 45.42 acre tract, the minimum buffer width
shall be 50 feet.
5. No piping is allowed except that minimum amount shown on the approved plans, and
that minimum amount necessary to direct runoff beneath an impervious surface such
as a road or to provide access.
Page 1 of 4

State Stormwater Management Systems
Permit No. SW8 950204
& All runoff directed into and through the vegetative buffer must flow through the buffer in
a diffuse manner.
7. All runoff directed into wetlands shall flow into and through the wetlands at a non -
erosive velocity of 2 feet per second or less.
8. Roof drains must terminate at the outer edge of the buffer.
9. The wet pond shown on the plans is incorporated only by reference, and is not an
enforceable part of the permit. The wet pond is required by the local government_ The
pond treats a parking lot that is located in an upland area away from surface waters
and drainageways. The drainage from the parking lot is therefore not required to be
treated in a wet pond by this low density permit.
II. SCHEDULE OF COMPLIANCE
No part or component of the approved stormwater management system shall be filled
in, altered, or piped, including the vegetated conveyances shown on the approved
plans, except for minimum driveway crossings, unless and until the permittee shall
have submitted a modification to the permit and received approval from the Division.
2. The facilities shall be constructed, operated and maintained in accordance with the
provisions of this permit, the approved plans and specifications, and the supporting
documents attached to this permit and on file with the Division.
3. The permittee is responsible for monitoring the project on a routine basis and verifying
that the proposed built -upon area does not exceed the allowable built -upon area.
4. The Director may notify the permittee when the permitted site does not meet one or
more of the minimum requirements of the permit. Within the time frame specified in the
notice, the permittee shall submit a written time schedule to the Director for modifying
the site to meet minimum requirements. The permittee shall provide copies of revised
plans and certification in writing to the Director that the changes have been made.
5. No person or entity, including the permittee, shall alter any component shown in the
approved plans and specifications. Prior to the construction of any modification to the
approved plans, the permittee shall submit to the Director, and shall have received
approval for modified plans, specifications, and calculations including, but not limited
to, those listed below. For changes to the project or SCM that impact the
certifications, a new or updated certification(s), as applicable, will be required and a
copy must be submitted to the appropriate DEQ regional office upon completion of the
modification.
a. Any modification to the approved plans and specifications, regardless of size
including the SCM(s), BUA, details, etc.
b. Redesign or addition to the approved amount of BUA or to the drainage area.
c. Further development, subdivision, acquisition, lease or sale of any, all or part of the
project and/or property area as reported in the approved plans and specifications.
d. Altering, modifying, removing, relocating, redirecting, regrading, or resizing of any
component of the approved SCM(s), the stormwater collection system and/or
vegetative conveyance shown on the approved plan.
e. The construction of any allocated future BUA.
f. The construction of any permeable pavement, #57 stone area, public trails, or
landscaping material to be considered a permeable surface that were not included
in the approved plans and specifications.
g. Other modifications as determined by the Director.
Page 2 of 4

State Stormwater Management Systems
Permit No. SW8 950204
6. Swales and vegetated conveyances shall be constructed in their entirety, vegetated,
and operational for their intended use prior to the construction of any built -upon
surface.
7. During construction, erosion shall be kept to a minimum and any eroded areas of the
swales or vegetated conveyances will be repaired immediately.
8. The permittee shall at all times provide and perform the necessary operation and
maintenance procedures as specified in the signed Operation and Maintenance
Agreement, such that the permitted stormwater management system functions as
designed and permitted.
9. Within 30 days of completion of the project, the permittee shall certify in writing that the
project has been constructed in accordance with the approved plans.
10. The permittee shall submit all information requested by the Director or his/her
representative within the time frame specified in the written information request.
III. GENERAL CONDITIONS
Any individual or entity found to be in noncompliance with the terms and conditions of
a stormwater management permit or the stormwater rules, is subject to enforcement
action in accordance with the procedures stated in North Carolina General Statute 143
Article 21.
2. Current Permittee Name or Address Changes: The permittee shall submit a
completed "Permit Information Update Application Form" (available on the Division
website) tote Division within 30 days to making any one or more of the following
changes:
a. A name change of the current permittee;
b. A name change of the project;
c. A mailing address change of the permittee;
3. Approved plans, application, supplements and specifications for projects covered by
this permit are incorporated by reference and are enforceable parts of the permit. The
permittee shall maintain a copy of the approved plans on site at all times.
4. The permit issued shall continue in force and effect until the permittee files a request
with the Division for a permit modification, transfer, or rescission; however, these
actions do not stay any permit conditions.
5. The issuance of this permit does not prohibit the Director from reopening and
modifying the permit, revoking and reissuing the permit, or terminating the permit as
allowed by the laws, rules, and regulations contained in Title 15A of the North Carolina
Administrative Code, Subchapter 2H.1000, and North Carolina General Statute 143-
215.1 et. al.
6. Unless specified elsewhere, permanent seeding requirements for the vegetated
conveyances must follow the guidelines established in the latest version of the North
Carolina Erosion and Sediment Control Planning and Design Manual.
7. Permit Transfer: This permit is not transferable to any person or entity except after
notice to and approval by the Director. The permittee shall submit a completed and
signed "Permit Transfer Application Form" (available on the Division website)
accompanied by the required fee and supporting documentation as listed on the form,
to the Division at least 60 days prior to any one or more of the following events:
Page 3 of 4

State Stormwater Management Systems
Permit No. SW8 950204
a. The sale or conveyance of the project area in whole or in part, except in the
case of an individual lot sale that is made subject to the recorded deed
restrictions and protective covenants;
b. Dissolution of the partnership, corporate, or LLC entity, subject to NCGS 55-14-
05 or NCGS 57D-6-07 and 08;
c. Bankruptcy;
d. Foreclosure, subject to the requirements of Session Law 2013-121;
8. The permittee is responsible for compliance with all permit conditions until such time
as the Division approves the transfer request. Neither the sale of the project, in whole
or in part, nor the conveyance of common area to a third party constitutes an approved
transfer of the stormwater permit.
9. The permittee grants permission to Division Staff to enter the property during normal
business hours for the purpose of inspecting the project for compliance.
10. The issuance of this permit does not preclude the Permittee from complying with and
obtaining any and all permits or approvals as required by any statutes, rules,
regulations, or ordinances, which may be imposed by any other Local, State or
Federal government agency having jurisdiction. Any activities undertaken at this site
prior to receipt of the necessary permits or approvals to do so is considered a violation
of NCGS 143-215.1, and subject to enforcement procedures pursuant to NCGS 143-
215.6.
Permit modified, updated and reissued this the 3rd day of June 2020.
NORTH CAROLINA ENVIRONMENTAL MANAGEMENT COMMISSION
.�/X, Brian Wrenn, Acting Director
Division of Energy, Mineral and Land Resources
By Authority of the Environmental Management Commission
Permit Number SW8 950204
Page 4 of 4

DEMLR USE ONLY
Date Eected
Fee Paid
Permit Number
0a
=
512 as
STORMWATER PERMITTING FORM 7: ECEIVE
MINOR MODIFICATION HAR 0 4 610
Standard Permitting Program — No Fee for Minor Modification
Express Permitting Program — See Express Fee ScheduleAy:
Only complete applications packages will be accepted and reviewed. This form and the required items (with
original signatures) must be sent to the appropriate DEMLR Regional Office, which can be determined by locating
the project on the interactive online map at: http://deg.nc.gov/contact/repional-offices.
This form is to only to be used by the:current pennittee to notify the Division of a minor
modification. Pursuant to Rule 15A NCAC 02H .1002 a minor modification is a change to the project that:
1) does not increase the net built -upon area; and/or
2) does not change the size or design of the SCM(s).
A. GENERAL INFORMATION
1. State Stormwater Permit Number: SW8 950204
2, Current Permit Holder's Company Name/Organization: New Hanover County
3. Signing Official's Name: Tim Burgess — -
4. Signing Official's Title: Deputy County Manager
5. Mailing Address: 230 Government Center Drive, Suite 195
City: Wilminqton State: NC ZIP: 28403
6. Street Address (if different):
City: State: ZIP:
7. Phone: [phone] Email: [e-mail]
8. Describe the minor modifications that you are requesting, including any revised BUA allocations (attach
additional pages or supporting tables similar to Section 1V.10 of the original application, if needed):
Minor realignment of multi -use path, no increase in BUA
B. SUBMITTAL REQUIREMENTS
Please mark "Y" to confirm the items are included with this form. Please mark W" if previously provided. If not
applicable or not available, please mark N/A.:
1. Two hard copies (with original signatures) and one electronic copy of this completed form.
rSL3P 2. Two hard copies and one electronic copy of the revised plan sheets (must be a revision of the
originally approved plan sheets).
3. If there is reallocation of lot BUA, a copy of the revised recorded deed restrictions and protective
covenants OR the proposed recorded deed restrictions and protective covenants documenting
the changes and a signed agreement to provide the final recorded document.
4. It applicable, the appropriate Express review fee.
Stormwater Permit Form 7: Minor Modification Page 1 of 2 July 14, 2017

C. CONTACT INFORMATION
1. The Design Professional who is authorized to provide information on the Applicant's behalf:
Design Professional's Name: Jeffrey B. Petroff, PE
Consulting Firm: Coastal Land Design, PLLC
Mailing Address: P.O. Box 1172
City: Wilmington State: NC Zip: 28402
Phone: [phone] Fax: [phone]
Email: :ipetroff(a)cideng.com _
2. [OPTIONAL) If you would like to designate another person to answer questions about the project:
Name & Title:
Organization:
Mailing Address:
City:
Phone:
Email:
D. CERTIFICATION OF PERMITTEE
State: I Zip:
ax:
I, Tim Burgess, Deputy County Managerthe current permittee, certify that I have
authorized the minor momcations listed in Section A and shown in the attached revised plan sheets. I further attest
that this information i,%/accuoate and complje to the best of my knowledge.
Signature:
ate: a ZO c7
I, Ppea
a Notary Public for the State ofCoun y of do hereby certify thatpersonallyred before me this the 2n day of O- 20� a(d)
acknowledge the due execution of the forgoing instrument. Witness my hand and c6icial seal,
(Notary Seal)
Notary Signature
My commission e
MAR 0
BY:
, QvrL P ,
Z 4' txOTAR), I&C�
R
Stormwater Permit Form 7: Minor Modiftcation Page 2 of 2 Oct 6, 2017

st5....
.. .
`? ,P!i, uric
to _.._
�PYualrlill��'ly,

Permit No.
sag' sa�o�
(to be provided by DEML R)
State of North Carolina
Department of Environment and Natural Resources
Division of Energy, Mineral and Land Resources
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
LOW DENSITY SUPPLEMENT
This farm may be photocopied for use as an original
A low density project is one that meets the appropriate criteria for built upon area and transports stormwater
runoff primarily through vegetated conveyances. Low density projects should not have a discrete stormwater
collection system as defined by 15A NCAC 2H .1002(18). Low density requirements and density factors can be
found in Session Law 2008-211, t5A NCAC 2H .1000, Session Law 2006-246 and the State of North Carolina
Stormwater Best Management Practice Manual. Curb and gutter systems are allowed provided they meet the
requirements in 15A NCAC 2H .1008(g).
I. PROJECT INFORMATION
Project Name : Castle Rayne Park
Contact Person: Tim Burgess, Assistant County Manager Phone Number: ( 910 )798-7184
Number of Lots:
Allowable Built Upon Area (BUA) Per Lot*:
Number of Dwelling Units Per Acre**:
Low Density Development (check one): ® without curb & gutter ❑ with curb & gutter, outlets to (check one):
❑ Swales ❑ Vegetated Area
*If lot sizes are not uniform, attach a table indicating the number of lots, lot sizes and allowable.buiit upon area for each lot.
The attachment must include the project name, phase, page numbers and provide area subtotals and totals. BUA shall be
shown in units of square feet.
**(Phase II Post -Construction [non -SA] only)
II. BUILT UPON AREA
Refer to DEMLR's forms and applications website for specific language that must be recorded in the deed
restrictions for all subdivided projects. (http://portal.ncdenr.orglwebllrlstate-stormwatet--forms does)
Complete the following calculation in the space provided below where:
• SA Site Area - the total project area above Mean High Water.
• DF Density Factor - the appropriate percent built upon area divided by 100.
• RA Road Area - the total impervious surface occupied by roadways.
• OA Other Area - the total area of impervious surfaces such as clubhouses, tennis courts, sidewalks, etc.
• No. of Lots - the total number of lots in the subdivision.
• BUA per Lot - the computed allowable built upon area for each lot including Ec;Ex i . us
surfaces located between the front lot line and the edge of pavement. JUN 12 2014
• Total allowable lot BUA - the computed allowable built upon area for all lot mbined.
• Total BUA from lot listing - the sum of built upon area allocated for each lot AY- -orm lots.
Form SW401-Low Density-Rev3-2/10/09 Page 1 of 4

L t
� 1 a
I C`aIrn;lntinn
For uniform lot sizes:
SA: ft2 x DF: — RA: ft2 -- (OA: ft2)= BUA per Lot = ft2
(No of Lots: )
For nonuniform lot sizes:
a. (SA: ft2 x DF: ) — (RA: ft2) — (OA: ft2) = Total allowable lot BUA = ft2
b. Total BUA from lot listing: sf. b must be � a
111. DESIGN INFORMATION
Complete the following table. If additional space is needed the information should be provided in the same
format as Table 1 and attached to this form. Rainfall intensity data can be found in Appendix 8.03 of the State
of North Carolina Erosion and Sediment Control Planning and Design Manual or at
http://hdse.nws.noaa.gov/hdsc/pfds/
Table 1. Swale design information based on the 10-vear storm.
Swale No:
Drainage
Area'(ac)
Impervious
.,Area ac
Grassed.,_
Area (ac)
G. �.
s,
Q
(cfs)„
Slope .
(%)
V,,»ow
(fps)
Vactul
. (f s)
`� Flow
p Deth°'(ft)
1
1.05
0.29
0.76
0.41
3.32
0.5
2.0
1.61
0.83
2
0.50
0.14
0.36
0.41
1.58
0.5
2.0
1.34
0.63
3
4
5
6
7
8
9
10
11
12
'
13
14
15
16
17
18
C
19
�A�
9fl1
20
�JVI\
M
corm SW401-Low Dens ity-Rev.3-2110I09 Page 2 of 4

I IV.,- kEQUIRED ITEMS CHECKLIS'C
The following checklist outlines design requirements per the North Carolina Administrative Code Section 15A
NCAC 2H .1000, NCDENR BMP Manual (2007), Session Law 2006-246, and Session Law 2008-21 1.
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 that the following requirements
have been met and supporting documentation is provided as necessary. If the applicant has designated an agent
on the Stormwater Management Permit Application Form, the agent may initial below. If any item is not met,
then justification must be attached. Only complete items n through p for projects with curb outlets.
Page/Plan
Initials Sheet No.
a. t
For projects in the 20 coastal counties: Per NCAC 2H.1005, a 50 foot wide vegetative buffer
is provided adjacent to surface waters. For Redevelopment projects, a 30' wide vegetative
buffer adjacent surface waters is provided.
b. t
For HQW or ORW projects outside the 20 coastal counties: A 30 foot wide vegetative buffer
is provided adjacent to surface waters.
C. t
For Phase II Post -Construction projects: All built upon area is located at least 30 feet
landward of all perennial and intermittent surface waters.
d.
Deed restriction language as required on form SWU-101 shall be recorded as a restrictive
covenant. A copy of the recorded document shall be provided to DWQ within 30 days of
platting and prior to the sale of any lots.
C.
Built upon area calculations are provided for the overall project and all lots.
,✓ f.
Project conforms to low density requirements within the ORW AEC. (if applicable per
15A NCAC 2H .1007)
f3P g.
Side slopes of swales are no steeper than 3:1; or no steeper than 5:1 for curb outlet swales.
�13P h.
Longitudinal slope of swales is no greater than 5%; for pion -curb outlet projects, calculations
for shear stress and velocity are provided if slope is greater than 5%.
�BP i.
At a minimum, swales are designed to carry the 10 year storm velocity at a non -erosive rate.
J.
Swales discharging to wetlands are designed to flow into and through the wetlands at a non -
erosive velocity (for this flow requirement into wetlands, non -erosive is velocity S 2 ft/s).
'W �' _ k. Swale detail and permanent vegetation is specified on the plans.
sBP 1. Swale detail provided on plans; includes grass type(s) for permanent vegetative cover.
�f# m. Swales are located in recorded drainage casements.
r✓ n." Length of swale or vegetated area is at least 100 feet for each curb outlet.
o." The system takes into account the run-off at ultimate built -out potential from all surfaces
draining to the system (delineate drainage area for each swale).
p.'t Curb outlets direct flow to a swale or vegetated area. 1EC IEIV
t Projects in the Neuse, Tar -Pamlico, Catawba River basins, and Randleman Lake y require additional i ers.
tt Only complete these items for projects with curb outlets. '���; j Z L�1
BY: _
Form SW401-Low Density-Rev.3-2/10/09 Page 3 of 4

. V. -WALE SYSTEM MAINTENANCE REQUIREMENTS
Mowing will be accomplished as needed according to the season. Grass height will not exceed six inches at
any time; and grass will not be mowed too close to the ground or "scalped".
2. Swales will be inspected monthly or after every runoff producing rainfall event for sediment build-up,
erosion, and trash accumulation.
3. Accumulated sediment and trash will be removed as necessary. Swales will be reseeded or sodded
following sediment removal.
4. Eroded areas of the swales will be repaired and reseeded. Swales will be revegetated as needed and in a
timely manner based on the monthly inspections. Side slopes must be maintained at the permitted slope.
5. Catch basins, curb cuts, velocity reduction devices, and piping will be inspected monthly or after every
significant runoff producing rainfall event. Trash and debris will be cleared away from grates, curb cuts,
velocity reduction devices and piping.
6. Swales will not be altered, piped, or filled in without approval from NCDENR Division of Energy, Mineral
and Land Resources.
' �QYR �luc�CWor� /S
I acknowledge and agree by my signa re below tha*Ivy,715f�NIILR
responsible for the performance of the six
. �deaic t otmaintenance procedures listed above./] b of any problems with the system or prior to any
changes to the system or responsible party.
Print Name and Title: Tim Burgess, Assistant County Manager
Address: 230 Government Center Drive, Suite 195
Phone
Signature:
Date:
Note: The legally responsible pa d trot he a homeowners association unless nrore than 5017o of the lots have been sold and a
resident of the subdivision has been named the president.
I, SU�5an J. __ di ld S , a Notary Public for the State of SLC " -% Car-01tnPCounty of
NQ W C1C�\{ 0 _C do hereby certify that C- personally appeared before me this
day of A, N-i' 22 , and acknowledge the due execution of the forgoing swale maintenance requirements.
Witness my hand and official seal,
Notary sig��i++r�i0900,11/
Ooz
b4Tq �p
=Z
10
Form SW401-1-ow Density-Rev.3-2/10/09
My commission expires
ECEIVE
JUN 12 2014
Page 4 of 4 BY:

.��. �. i
.. _._. .,
.A ..'.,t '�' � 1 � _ .1 � _' 4e J f.
y U �• r l `� 'r J �'s
�I
r
M
�� 1.

Permit No.
(to be provided by D WQ)
AURA
h r
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 Ifo must be printed, fitted out and submitted along with all of the required information,
I:. PROJECT INFORMATION,';j: � )) i�'W i r ,
,��.`1'8 6 ,3t`.11
Project name Castle Hayne Park
Contact person Jeff Petroff, P.E
Phone number 910-254-9333 x 1002
Date
Drainage area number
III; rDESIGN INFORMATION.. .'r,J. t:
Site Characteristics
Drainage area 300,077 ft3
Impervious area, post -development 39,840 f?
% impervious 13.28 %
Design rainfall depth 1.5 in
Storage Volume: Non -SA Waters
Minimum volume required 6,359 ft3
Volume provided 7,380 ft3
Storage Volume: SA Waters
1.5' runoff volume
ft3
Pre -development 1-yr, 24-hr runoff
ft3
Post -development 1-yr, 24-hr runoff
ft
Minimum volume required
It,
Volume provided
ft3
Peak Flow Calculations
Is the prelpost control of the 1 yr 24hr storm peak flow required?
N (Y or N)
1-yr, 24-hr rainfall depth
in
Rational C, pre -development
(unitless)
Rational C, post -development
(unitless)
Rainfall intensity: 1-yr, 24-hrstorm
irdhr
Pre -development 1-yr, 24-hr peak flow
0sec
Post -development 1-yr, 24-hr peak flow
ft3lsec
Pre/Post 1-yr, 24-hr peak flow control
ft3lsec
Elevations
Temporary pool elevation
24.25 fmsl
Permanent pool elevation
23,00 fmsl
SHWT elevation (approx. at the perm. pool elevation)
23.5D fmsl
Top of 1Oft vegetated shelf elevation
23.50 fmsl
Bottom of 1 Oft vegetated shelf elevation
22,50 fmsl
Sediment cleanout, top elevation (bottom of pond)
18.00 fmsl
Sediment cleanout, bottom elevation
17.00 fmsl
Sediment storage provided
1.00 ft
Is there additional volume stored above the state -required temp. pool?
y (Y or N)
Elevation of the top of the additional volume
24.3 fmsl
OK, volume provided is equal to or in excess of volume required.
OK ECEIVE
J U N 12 2014
8Y:
Form SW401-Wet Detention Basin-Rev,9-4118112 Parts I, & II. Design Summary, Page 1 of 2

0

Permit No.
(to be provided by DWO)
II: bDSIGN INFORMATION. ` ,.�,; ` 1 `) t ` V *a rt ­s >
Surface Areas
Area, temporary pool
8,655 ft2
Area REQUIRED, permanent pool
4,801 ftZ
SAIDA ratio
1.60 (unitless)
Area PROVIDED, permanent pool, Ap,,,_Pod
6,105 ft`
OK
Area, bottom of 1 Oft vegetated shelf, Aeoi ,1eir
4,498 ft`
Area, sediment cleanout, lop elevation (bottom of pond), Ate, pl�d
523 ft`
Volumes
Volume, temporary pool
7,380 63
OK
Volume, permanent pool, Vpef _p d
13,151 tt3
Volume, forehay (sum of forebays if more than one forebay)
2,618 ft'
Forebay % of permanent pool volume
19.9% %
OK
SAIDA Table Data
Design TSS removal
90 %
Coastal SAIDA Table Used?
Y _ (Y or N)
Mountain/Piedmont SAIDA Table Used?
N (Y or N)
SAIDA ratio
1,60 (unitless)
Average depth (used in SAIDA table):
Calculation option 1 used? (See Figure 10-2b)
N (Y or N)
Volume, permanent pool, Vpef,,,_Pd
13,151 ft'
Area provided, permanent pool, Ate, per,
6,105 ft'
Average depth calculated
ft
Need 3 ft min.
Average depth used in SAIDA, day, (Round to nearest 0.5ft)
ft
Calculation option 2 used? (See Figure 10-2b)
Y, (Y or N)
Area provided, permanent pool, APefm_,d
6,105 ft`
Area, bottom of 10ft vegetated shelf, Ate, d,,d
4,498 6`
Area, sediment cleanout, top elevation (bottom of pond), Ab,_p�d
523 6z
'Depth' (distance b/w bottom of 1Oft shelf and top of sediment)
4.50 ft
Average depth calculated
3.00 ft
OK
Average depth used In SAIDA, dav, (Round to down to nearest 0.5ft)
3.0 ft
OK
Drawdown Calculations
Drawdown through orifice?
y (Y or N)
Diameter of orifice (if circular)
1,25 in
Area of orifice (if -non -circular)
in
Coefficient of discharge (Cu)
0.60 (unitless)
Driving head (HP)
0.49 ft
Drawdown through w&9
N (Y or N)
Weir type
(unitiess)
Coefficient of discharge (C„,)
(unitless)
Length of weir (L)
ft
Driving head (H)
ft
Pre -development 1-yr, 24-hr peak Flow
ft3lsec
Post -development 1-yr, 24-hr peak Flow
ft3lsec
Storage volume discharge rate (through discharge orifice or weir)
0.03- ft3lsec
Storage volume discharge rate greater than pre-dev. 1 yr24hr,
Storage volume drawdown time
2.83' days
OK, draws down in 2-5 days.
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 -cut?
Drain mechanism for maintenance or emergencies is:
3:1 OK ECEIVE
10 :1 OK
10.0 ft OK
3:1 OK t� .l1!!1M 2 2014
3.0.:1 OK 1
Y (Y or N) OK
1.0 ft OK BY:
N (Y or N) OK
Y (Y or N) OK
N (Y or N) Required to capture all runoff from the ultimate build -out
Yes, portable pump
Form SW401-Wet Detention Basin-Rev.9-4118112 Parts I. & II. Design Summary, Page 2 of 2

Permit Number:
(to he provided by DWQ)
Drainage Area Number:
Wet Detention Basin 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.
The wet detention basin system is defined as the wet detention basin,
pretreatment including forebays and the vegetated filter if one is provided.
This system (check one):
❑ does ® does not incorporate a vegetated filter at the outlet.
This system (check one):
❑ does ® does not incorporate pretreatment other than a forebay.
Important maintenance procedures:
— Immediately after the wet detention basin is established, the plants on the
vegetated shelf and perimeter of the basin should be watered twice weekly if
needed, until the plants become established (commonly six weeks).
— No portion of the wet detention pond should be fertilized after the first initial
fertilization that is required to establish the plants on the vegetated shelf.
— Stable groundcover should be maintained in the drainage area to reduce the
sediment load to the wet detention basin.
— If the basin must be drained for an emergency or to perform maintenance, the
flushing of sediment through the emergency drain should be minimized to the
maximum extent practical..
— Once a year, a dam safety expert should inspect the embankment.
After the wet detention pond is established, it should be inspected once a month and
within 24 hours after every storm event greater than 1.0 incljUjEPf.'5F4V1Gft
Coastal County). Records of operation and maintenance shWJUN
kept in a
Iocation and must be available upon request. 12
Inspection activities shall be performed as follows. Any pro
be repaired immediately.
BMP element:
Potentialproblem:
How I will remediate theproblem:
The entire BMP
Trash/debris is present.
Remove the trash/debris.
The perimeter of the wet
Areas of bare soil and/or
Regrade the soil if necessary to
detention basin
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.
Vegetation is too short or too
Maintain vegetation at a height of
long.
approximatel six inches.
Form SW40I-Wet Detention Basin O&M-Rev.4 Page 1 of 4

Permit Number:
(to be provided by DWQ)
Drainage Area Number:
BMP element:
Potentialproblem:
How I will remediate theproblem:
The inlet device: pipe or
The pipe is clogged.
Unclog the pipe. Dispose of the
swale
sediment off -site.
The pipe is cracked or
Replace the pipe.
otherwise damaged.
Erosion is occurring in the
Regrade the swale if necessary to
swale.
smooth it over and provide erosion
control devices such as reinforced
turf matting or riprap to avoid
future problems with erosion.
The forebay
Sediment has accumulated to
Search for the source of the
a depth greater than the
sediment and remedy the problem if
original design depth for
possible. Remove the sediment and
sediment storage.
dispose of it in a location where it
will not cause impacts to streams or
the BMP.
Erosion has occurred.
Provide additional erosion
protection such as reinforced turf
matting or riprap if needed to
prevent future erosion problems.
Weeds are present.
Remove the weeds, preferably by
hand. If pesticide is used, wipe it on
the plants rather than spraying.
The vegetated shelf
Best professional practices
Prune according to best professional
show that pruning is needed
practices
to maintain optimal plant
health.
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 to establish the
ground cover if a soil test indicates
it is necessar .
Weeds are present.
Remove the weeds, preferably by
hand. If pesticide is used, wipe it on
the plants rather than spraying.
The main treatment area
Sediment has accumulated to
Search for the source of the
a depth greater than the
sediment and remedy the problem if
original design sediment
possible. Remove'the sediment and
storage depth.
dispose of it in a location where it
will not cause impacts to streams or
the BMP.
Algal growth covers over
Consult a professional to remove
50% of the area.
and control the algal growth.
Cattails, phragmites or other
Remove the plants by wiping them
invasive plants cover 50% of
with pesticide (do not spray).
the basin surface.
F C
}INN i 12014
Form SW40I-Wet Detention Basin O&M-Rev.4 Pao of 4
• BY:

Permit Number:
(to be provided by DWQ)
Drainage Area Number:
BMP element:
Potential problem :
How I will remediate the problem:
The embankment
Shrubs have started to grow
Remove shrubs immediately.
on the embankment.
Evidence of muskrat or
Use traps to remove muskrats and
beaver activity is present.
consult a professional to remove
beavers.
A tree has started to grow on
Consult a dam safety specialist to
the embankment.
remove the tree.
An annual inspection by an
Make all needed repairs.
appropriate professional
shows that the embankment
needs repair. if applicable)
The outlet device
Clogging has occurred.
Clean out the outlet device. Dispose
of the sediment off -site.
The outlet device is damaged
Repair or replace the outlet device.
The receiving water
Erosion or other signs of
Contact the local NC Division of
damage have occurred at the
Water Quality Regional Office, or
outlet.
the 401 Oversight Unit at 919-733-
1786.
The measuring device used to determine the sediment elevation shall be such
that it will give an accurate depth reading and not readily penetrate into
accumulated sediments.
When the permanent pool depth reads 5.0 feet in the main pond, the sediment
shall be removed.
When the permanent pool depth reads 3.0 feet in the forebay, the sediment
shall be removed.
Sediment Removal M. 20.00
Bottom Elevatio 1 L.-
FOREBAY
BASIN DIAGRAM
6611 in the blanks)
/Volume'
-ft Min.
Sediment
Storage
Form SW40I-Wet Detention Basin O&M-Rev.4
Permanent Pool Elevation 23.00
Pool
1------Sediment Removal Elevation 18.00 Volume
Bottom Elevation
MAIN POND
ECGIVE
J U N 12 2014
BY. LJ
1-f� n.
Sediment
Storage

Permit Number:
(to be provided by DWQ)
Tara D+4ekworth is
I acknowledge and agree by my signature below that reams;oSsi�le for the .«s
performance of the maintenance procedures listed above. eeo noti y D1'UQ of any
problems with the system or prior to any changes to the system or responsible party.
Project nanie: Castle Hayne Park
BMP drainage area number: I
Print name: Tim Burgess
Title: Assistant County anager
Address: 230 Government Center Drive, Suite 195
Phone: [phone]$4-\
Signature: `/ l-
Date:}�.� /o5J/ V
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, _,r�t15C).n J . _Sa't (d I , a Notary Public for the State of
t�Offln CAckrc)tij nc , County of god kA(DnCNQ_(` , do hereby certify that
Ti i'�n In\I C_. 1_ l][ C���S personally appeared before me this 22
day of pnr(i , 20[4 , and acknowledge the due execution of the
forgoing wet detention basin maintenance requirements. Witness my hand and official
1::Oc'
NOTg9� O
��CIC
�6ti4 `
�.'' °UNNT C: %'.
SEAL
My commission expires 7{_} i<1P._ -1 l . '4�
�ECEBVED
Jul 1 1 2014
BY:
Form SW401-Wet Detention Basin O&M-Rev.4 Page 4 of 4

�•i ..'7 +�ti'i. .'. �. Y. i 3
.�
i
• 1
'�''
S
�
y�,
p... . � , x d..
a ._ ..
}
3

Permit No
(to be provided by Dwe)
III:.REQUIREDiTEMSCHECKLIST q
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.
P
i. 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.
7be
_
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.
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.
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.
e"lex
5. A table of elevations, areas, incremental volumes & accumulated volumes for overall pond and for forebay,
to verify volume provided.
6. A construction sequence that shows how the wet detention basin will be protected from sediment until the
entire drainage area is stabilized.
7. The supporting calculations.
8. A copy of the signed and notarized operation and maintenance (0&M) agreement.
9. A copy of the deed restrictions (if required).
10. A soils report that is based upon an actual field investigation, soil
�G EAlt;l�t
ounty
soil maps are not an acceptable source of soils information.
1UN 12 2014
BY:
Form SW401-Wet Detention Basin-Rev.9-4118112 Part Ill. Required Items Checklist, Page 1 of 1