SW7060405_HISTORICAL FILE_20060519

STORMWATER DIVISION CODING SHEET
POST -CONSTRUCTION PERMITS
PERMIT NO.
SW���
DOC TYPE
❑ CURRENT PERMIT
❑ APPROVED PLANS
HISTORICAL FILE
DOC DATE��
aJ
YYYYMMDD

Thomas Engineering, PA
403-C Airport Road
P. O. Box 1309, New Bern, NC 28563
252.637.2727 fax:[phone]
email: [e-mail]
FEDERAL EXPRESS
Tracking # 7921 0114 2914
To: Stormwater Management Section
Division of Water Quality
943 Washington Square Mail
Washington, NC 27889
Attn: Roger Thorpe
Re: Stormwater Plan
Tucker Creek Townes
Havelock, Craven County
2001-023
Dear Roger,
May 17, 2006
mAY 19 2006
DWQ-WARD
Please find enclosed two copies of the Revised Stormwater Management Plan drawings
per your comment letter dated May 11, 2006for the referenced project for your approval.
In regards to the comment on the vegetative shelf, we feel that for the size pond, six
feet of shelf is adequate and to increase the width of the shelf to 10 feet would
significantly reduce the volume of the pond. At the present design of 6 feet, the shelf
width is more than what would be proportional to the pond surface area when
considering a 10 foot shelf for a pond of/z acre or so.
If you have any questions or comments, please do not hesitate to call. I hope you are
doing well.
Since y,
ohr� G. Thomas, P.E.
Encl
Cc wlencl: Patrick McCullough

Michael F. Easley, Governor
William G. Ross Jr., Secretary
North Carolina Department of Environment and Natural Resources
May 11, 2006
Mr. Patrick McCullough
Tucker Creek Townes, LLC
604 East Main Street
Havelock, NC 28532
Subject: Stormwater Review SV 7060405
Tucker Creek Townes
Craven County
Dear Mr. McCullough:
Alan W. Klimek, P.E. Director
Division of Water Quality
This office received a Coastal Stormwater permit application and plans for the subject project on April 11,
2006, A preliminary review of your project indicates that before a State Stormwater permit can be issued the
following additional information is needed:
The plan detail of the wet pond outlet does not give the size of the small diameter orifice. Please
correct.
The 6:1 vegetated shelf around the wet pond should be at least 10 feet wide. If this cannot be
provided please explain.
3. There is a cross section labeled "Z — Z" on page 3 of 3 of the plans. I cannot find "Z — Z" on page 2 of
3.
The above requested information must be received in this office prior to June 11, 2006 or your
applications will be returned as incomplete. The return of these projects will necessitate resubmittal of all required
items including the application fees. If you need additional time to submit the required information, please mail or
fax your request for time extension to this office at the Letterhead address.
You should also be aware that the Stormwater Rules require that the permit be issued prior to any
development activity. Construction without a permit is a violation of 15A NCAC 2H.1000 and• North Carolina
General Statute 143-2151 and may result in civil penalties of up to $25,000 per day.
If you have questions, please feel free to contact me at [phone].
/Sincerely,
Roger K. Thorpe
Environmental Engineer
Washington Regional Office
cc: Thomas Engineering, PA
Washington Regional Office
North Carolina Division of Water Quality Internet: www.ricwatercigality.org One
943 Washington Square Mall Phone [phone] NorthCaroiina
Washington, NC 27889 Fax [phone] Natumllry
An Equal Opportunity/Affirmative Action Employer— 50% Recycled110% Post Consumer Paper �/A

Thomas Engineering, PA
403-C Airport Road
P. O. Box 1309, New Bern, NC 28563
252.637.2727 fax:[phone]
email: [e-mail]
FEDERAL EXPRESS
Tracking # 7927 1002 0517
To: Stormwater Management Section
Division of Water Quality
943 Washington Square Mall
Washington, NC 27889
Attn: Roger Thorpe
Re: Stormwater Plan
Tucker Creek Townes
Havelock, Craven County
2001-023
Dear Roger,
RECEO E
APR ? 1 2006
DWQ-WARO
April 10, 2006
Please find enclosed the Stormwater Management Plan Submittal for the referenced
project for your approval. Enclosed items include the original Stormwater Management
Permit Application Form and one copy, the original Wet Detention Basin Supplement
and one copy, and two copies each of the Stormwater Report and Plans along with check
# 6164 in the amount of $ 420.00 for the Stormwater Permit Fee. I have also attached the
compliance sheet from DWQ concerning the area marked on the plans as exempt from
the Neuse River Buffer Rules.
If you have any questions or comments, please do not hesitate to call. I hope you are
doing wev
Sing6rely
. Thomas, P.E.
Cc w/encl: Patrick McCullough

rUNK
ew
O
NORTH CAROLINA DEPARTMENT OF COPY
1.1 2006 ENVIRONMENT AND NATURAL RESOURCES
�� DiVLSION OF WATER QIIAiITY
�1
uVVQ_WA` NOTICE FOR REQUIREMENT OF COMPLIANCE OF EMC RULES FOR
PROTETI CON AND MAINTENANCE OF EXMING RIPARL)►N AREAS
PROJECT # — OZ Q COUNTY � ,-a. v 4- r DWQ OFFICE O
VERSION: NEUSE (15A NCAC 2B .0233) TAR-PAKLICO (15A NCAC 2B .0259)
CATAWBA(15A NCAC 2B .0243) RANDLEIHAN (15A NCAC 2B .0250)
OTHER
j� .ram �. minn
EXEMPT _ K IJ NOT EXF30'
(DWQ INITIALS) (DWQ INITIALS)
Property Owner's Mz=
Phone Number (riome�
Address Wl-._
City �. rj e—t
Pro'ect Location (Nearest
�uLk4 r C r. r-
l�rf r91 r rye t,. 1
to Road, N
(Business)
State
W$ter Body, etc)
As indicated on attached map initialed by staff on DZ
Description of Pronosed Proiect .
rA
Descriudon of Site
r-
r,
m,r 7r r
VIewcrd
Violation rioted on site YES IO if yes, a Notice at Violation will be forwarded from the appropriate regional ot'fice. .
Tjphs-acoKsed project which is to be located and constructed as described above Is hereby determined as
('EXEMPIINOT EXEMPT from compliance I
the requirements of the aforementioned rules as It applies to section
. This determination does not alleviate the
necessity of your obtaining any other
Property Owner's/Agent's
DWQ Official's Signature
Federal, or Local authorteatlon.
Date of Determination
'This project may require a section 4041401 p rmit Ora CAMA Permit for the pimp I e, I sedvitr. Inquirles a6auid ba directed to tha DWQ C 02i
Office at [phone]. Washington Office A (M) 946-WI. Raleigh OIIIee at (919) Sn47M WWaiagft afte at (910) 393,iM Wimma $a,—
Ot11ce at 036) 7714630. Asheville Office at (SM) 251-6209, Fayetteville Offiee at (910) 4W4541, or Moortarille QIDee at [phone].

REVISED
ENGINEERING REPORT
FOR
STORMWATER IMPROVEMENTS
AT
Tucker Creek Townes
Craven County
2001-023
OWNER: Tucker Creek Townes, LLC
604 East Main Street
Havelock, NC 28532
APR 1 1 2006
DWQ-WARD
CONSULTING ENGINEER: THOMAS ENGINEERING, P.A.
P.O. BOX 1309
NEW BERN, N.C. 28563-1309
ci
252-637-2727
' e4�
252-636-2448 fax
a
email: [e-mail]
Page 1 of 7

NARRATIVE
PROJECT DESCRIPTION
This project consists site development work to include installation of utilities, streets,
parking, site grading, soil stabilization, and construction of townhouses on 5.93 acres
(land disturbance of 3 acres) of land proposed for multi -family development for
Tucker Creek Townes.
SITE DESCRIPTION
This site varies between elevation 0.00 ft and 28.00 ft NGVD and was previously
cleared and grubbed under Erosion and Sedimentation Control Plan No. Crave-2003-
024. There are some 404 wetlands that borders Tucker Creek and Tucker Creek is
subject to the Neuse River Buffer Rules. The run that borders the north side of the
property between Tucker Creek Townes and Tucker Creek Section Three is not
subject to the Neuse River Buffer Rules (exemption attached).
ADJACENT PROPERTY
This tract is bordered on the north by Tucker Creek, on the west by US 70 Highway,
on the south by Sermons Blvd, and on the east by the Tucker Creek Estates Section
Three subdivision.
SOILS
The Craven County Soil Survey indicates soil types on this tract are: Craven silt
loams on the higher elevations, which are moderately well drained soils; Suffolk
loamy sands on the side slopes which are well drained soils; and Masontown mucks
which are located along the wetland fringes of Tucker Creek.
STORMWATER MANAGEMENT
Overall, this project has less than 30% impervious cover; however, if you exclude the
wetlands, the project has 53% of impervious cover. Therefore, this development,
having one drainage area, is being considered as a high density development with
percent of impervious cover being 53%. Stormwater will be treated in a stormwater
wet detention pond before being discharged into an existing wetlands that border the
project.
Page 2 of 7

SUPPORTING DOCUMENTS
1. Drainage Basin # 1
A. Site Data
1. Built Upon Area
Streets (asphalt)& sidewalks (concrete) .................... 42,000 sf
Buildings......................................................... 24,500 sf
Total Built Upon Area ..................................... 66,500 sf (1.5266 ac)
2. Total Area (less wetlands) .................................. 125,888 sf (2.89 ac)
3. Percent Impervious Area
(66,500 sf / 125,888 sf )(100) = 53 % > 30% (High Density)
B. Determination of Wet Detention Pond Surface Area
1) Reference Attachment "A" 90% TSS removal
2) Proposed Pond Depth: 6.0 ft
3) Imperious Percent: 53 %
4) Drainage Area: 125,888 sf
5) Surface Area/Drainage Area: 2.91%
(Interpolated from attachment "A") 90% TSS Removal
Where:
Impervious % = 53 %
Permanent Pool = 6.0 ft
6) Pond Surface Area:
a) Required 125,888 sf x 0.0291 = 3664 sf
b) Provided Design pond surface area (SA)= 3776 sf (@ permanent pool
elevation)
C. Determination of required storage following a one inch
rainfall event:
Page 3 of 7

Where C for building roofs
= 1.0
paved areas
= 0.9
green areas
= 0.2
1) Building Roofs: (24,500 sf)(1.0)(1 inch)(1 ft / 12 inch) = 2042 cf
2) Paved Areas: (42,000 sf)(0.9)(1 inch)(1 ft / 12 inch) = 3150 cf
3) Green Areas: (59,388 sf)(0.2)(1 inch)(i ft/ 12 inch) = 990 cf
4) Required Total Storage Volume = 6182 cf
5) Storage Depth (1 inch rainfall)(h)
H = Volume/SA
H = 6182 cf I [(3776 sf + 5192 so 12]
H = 1.4 ft ( 1.5 ft provided)
6) Provided Storage Volume = 6727 cf
D. Draw down determination (based on 1 inch rainfall)
1) Q (2 dys) = 4484 cf / (2 dys)(24 hrs/dy)(60 min/hr)(60/sec/min) = 0.026 cfs
2) Q (5 dys) = 4484 cf I (5 dys)(24hrs/dy)(60min/hr)(60/sec/min) = 0.0104 cfs
3) Orifice Size
a) Orifice Formula
Area = [Q/(Cd times the square root, of (2gh))] x 144 sqin/sf
Where h = H/2 = .75 ft
Cd = 0.6
g = 32.174ft/sec
b) Area for Q (2dys)
Area = [0.026 cfs / 0.6 times by the square root of (2g .75 ft))](144 sqin/sf)
Area = 0.90 sq in
Pipe Diameter = 2 times the square root of 0.90 / Pi = 1.07 in
c) Area for Q (5dys)
Area = [0.0104 cfs / 0.6 times the square root of (2g .75 ft))](l 44 sgin/sf)
Area = 0.36 sq in
Pipe Diameter = 2 times the square root of 0.361 Pi = 0.23 in
Page 4 of 7

d) Selected Orifice Size
Use 314 in orifice
E. Runoff calculation for riser sizing and overflow:
1) Rational Method Q=CIA
Where Q = Peak rate of runoff (cfs)
C = Runoff coefficient
Building Roofs = 1.0
Paved Areas = 0.9
Green Areas = 0.2
I = Average intensity of rainfall (inches)
(I Oyr)
A = Drainage area (acres)
2) Determination of Peak Flow Q
C = (24,500 so(1.0)+(42,000 sf)(0.9)+(59,388 sf)(0.2)
70,874 sf
C= 0.59
H (Height difference) = 4 ft
L (length of travel) = 600ft
Tc (time of Concentration = 5.0 min
For i=7.1 in
10
Q=CIA
Q = (0.59)(7.1 in)(2.89 ac) =12.11 cfs
10
For i=8.1 in
25
Q = (0.59)(8.1 in)(2.89 ac) = 13.81 cfs
25
For i = 10.2 in
100
Q = (0.59)(10.2(2.89 ac) = 17.39 cfs
100
F. Outlet pipe & riser determination
Page 5 of 7

1. Riser Pipe
1.5
Q = 3.33(L-0.2H) H (Weir overflow formula for riser determination)
Q = 12.11 cfs
1.0
H=6in
L=10ft
Riser diameter "d" = L 1 pi = 3.18ft (Use 48 in diameter riser)
2. Outlet Pipe = 36 in (see exhibit ")
G. Calculate Emergency Overflow
1. Calculate overflow width
1.5
Q = 3.33(L-0.2H) H
Where Q = Flow (cfs)
L = length of weir (ft)
H = Weir Head (ft)
Solve for L where Q = 17.39 cfs
100
H=6in
L = 15 ft @ 6 in head (Use 15 ft opening)
Page 6 of 7

Exhibits
Page 7of7

Worksheet Riser Outlet Pipe
Worksheet for Circular Channel
Project Description
Project File
c:lprogram fileslhaestadlfmw12001-023.fm2
Worksheet
Riser Outlet Pipe
Flow Element
Circular Channel
Method
Manning's Formula
Solve For
Channel Depth
Input Data
Mannings Coefficient 0.024
Channel Slope 0.005000 ft/ft
Diameter 30.00 in
Discharge 13,81 cfs
Results
Depth
21.8
in
Flow Area
3.83
ft2.
Wetted Perimeter
5.11
ft
Top Width
2.23
ft
Critical Depth
1.25
ft
Percent Full
72.74
Critical Slope
0.015425 ft/ft
Velocity
3.61
ft/s
Velocity Head
0.20
ft
Specific Energy
2.02
ft
Froude Number
0.49
Maximum Discharge
16.90
cfs
Full Flow Capacity
15.71
cfs
Full Flow Slope
0.003864
ftlft
Flow is subcritical.
04/10/06 FlowMaster v5.11
03:47:49 PM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 [phone] Page 1 of 1

Cross Section Riser Outlet Pipe
Cross Section for Circular Channel
Project Description
Project File
cAprogram fileslhaestadlfmw12001-023.fm2
Worksheet
Riser Outlet Pipe
Flow Element
Circular Channel
Method
Manning's Formula
Salve For
Channel Depth
Section Data
Mannings Coefficient
0.024
Channel Slope
0.005000 ft/ft
Depth
21.8 in
Diameter
30.00 in
Discharge
1181 cfs
0AI 1 M
30.00 in
1
V N
H 1
NTS
04/10/06 FlowMaster v5.11
03:47:57 PM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 [phone] Page 1 of 1