SW8930217_Historical File_19930402

JOSEPH S. HILL, J& and ASSOCIATES
CONSULTING ENGINEERS and PLANNERS MAILING ADDRESS:
1602 HARBOUR DRIVE POST OFFICE BOX 5592STA. 1
WILMINGTON, NORTH CAROLINA WILMINGTON, N.C. 28403.4155
TELEPHONE [phone]"
March 26, 1993
Ms. Linda Lewis
N.C. Division of Environmental Management
127 Cardinal Drive Extension
Wilmington, North Carolina 28405-3845
Subject: Submittal of Additional Information
Stormwater Project No. 930217
Ocean Side Place
Dear Ms. Lewis:
Enclosed is the following additional information you requested during
your review of the stormwater plan submittal for Ocean Side Place.
1. Velocity calculations for main outlet swales (5:1 side slopes)
showing that they will not erode are enclosed.
2. The plans have been changed to show the project name as Ocean
Side Place.
3. The reserved area behind lots 198, 199, 219, 220, 221, 224,
225, and 226 is reserved as an undeveloped green area. A
statement is added to the deed restrictions which prohibits
impervious cover on this area.
Please consider this information in continuing your review of the
stormwater plan,
JSH/pat
attachments
Sincerely,
JOSEPH S. HILL, JR. and ASSOCIATES
C s. , �.
Jos h. S. Hill, Jr., P.E.
STORMWATER
U
W MAR 2 6 1993
u�m
�� 936Z11

Ms. Linda Lewis
Ocean Side Place
Page 2
VERIFICATION
/��/� 7�• �Strw personally appearing before me and, being
first duly sworn, says that the information contained in the application
and in the exhibits attached hereto are true to the best of his/her
knowledge and beliefs.
This % /)day of Chu a 1993
NOTARY PUBLIC
.eAy—
ADDRESS
My Commission Expires /C)43 93
cc: Joseph S. Hill, Jr. and Assoc.

OCEAN SIDE PLACE
SWALE VELOCITY CALCULATIONS
MAIN OUTLET SWALES
Calculate velocity in main outlet swales. "Use worst case" flow
through outlet swale between lots 80 and 81 at north corner of project.
Runoff Calculations
Use rational formula (Q = CiA) to estimate runoff flow:
Q = runoff (CFS)
i = intensity (10-yr. storm) = 3.2 in/hr.
A = contributing area (acres) = 7.5 AC impervious; 17.5 AC pervious
Tc (time of concentration) = 35 min. STORMWATER
Q(.impervious) = 1.0 x 3.2 x 7.5 = 24.0 CFS E � U L bu
Q(Pervious) = .2 x 3.2 x 17.5 = 11.2 CFS
Total Runoff = 35.2 CFS MAR 2 6 1993
Depth of Flow
Calculate depth of flow using Manning's equation for .trapezoid channels
(.see attached nomograph from figure 8.05d of-N.C., Erosion and'Sediment
Control'Planni►ig aAd�Design'Manual).

Given
that:
S
= .02
Q
= 35.2
N
= .03
B=2
Z=5
Therefore:
Qn = 1.05
d/B = 0.58'
d = 0.58'(2) = 1.16' (depth of flow in channel)
Channel Velocity Calculations:
1:49 x r2/3 x s1/2
Use Manning's equation V = n to determine
runoff velocity through main outlet swale.
V = velocity (FPS)
r = hydraulic radius = .706
s = bottom slope = .002
V = 1.49(.706)'67 x .002*5
.03
V = 1.75 FPS
Velocity will be less than 2.5 FPS allowable for bare soil during the
establishment of grass cover.

Appendices
d
o
B
N N
v cp
v
_
NOTE: Project horizontal from Z = 0 scale
0.01
d 1
to obtain values for Z= 1 to 6
z
a
0.02
B
(ft)
0.03
S
40
0.1
Q n
0.04
0.08
(Ft3/S).
30
0.05
0.06
20
0.06
0.05
20
0.08
0.04
10
c
0.1
0.03
8.0
J
fi.0 .
c 10
0.02
5.0
c
8
4A
'
3.0
6 j
02
5 %
2.0
0.01
e
4;
0.3
Q.008`
3
0.006
\`
0.4
0.005
0.8
\\
'
\�
0.5
0.004
0.5
\
0.4
\\
0.6
0.003
�
J*# Ocean Soda placa�
0.002
02\1%
�/$ o.60
0.8
\
1.0
�
\0, Example:
0.1
0.001
0.08
Given: Find: Solution:
S-0.01 d an 0.3
0.06
a = 10 ft3/S d/B = 0.14
0.05
n = 0.03 d - 0.14(4) = 0.56 ft
B=4ft
0.04
Z = 4
0.03
0.02
Figure &05d Solution of Manning's equation for trapezoidal channels of various side slopes.
8.05.11

Appendices
Table 8.05d
Maximum Permissible
Velocities for Unprotected
Solis in Existing Channels.
Sample Problem 8.05a
Design of a
grass -lined channel.
Materials
Maximum Permissible
Velocities (fps)
Pine Sand noncolloidal)
2.5
Sand Loam (noncolloidal)
2.5
Silt Loam (noncolloidal)
3.0
Ordinary Firm Loam
3.5
Fine Gravel
5.0
Stiff Clay (very colloidal)
5.0
Graded, Loam to Cobbles (noncolloidal)
5.0
Graded, Silt to Cobbles (colloidal)
5.5
Alluvial Silts (noncolloidal)
3.5
Alluvial Silts (colloidal)
5.0
Course Gravel (noncolloidal)
6.0
Cobbles and Shingles
5.5
Shales and Hard Pans
6.0
Given:
Design Qto - 16.6 cfs
Proposed channel grade - 20%
Proposed vegetation: Tall fescue
Soil: Creedmoor (easily erodible)
Permissible velocity, Vp - 4.5 ft/s (Table 8.05a)
Retardance class: "8' uncut, "D" cut (Table 8.05c).
Trapezoidal channel dimensions:
designing for low retardance condition (retardance class D)
design to meet Vp.
Find:
Channel dimensions
Solution:
Make an initial estimate of channel size
A - QN; 16.6 cfs/4.5 ft/sec - 3.69 ft2
Try bottom width . 3.0 ft
Z-3
A=bd+Zd2
P-b+2d
An iterative solution using Figure 8.05a to relate flow depth to
Manning's n proceeds as follows: Manning's equation is used
to check velocities
d (ft) A (ft) R (ft) n V (fps) Q (cfs) Comments
0.8 4.32 0.54 0.043 3.25 14.0 V<Vp OK,
Q<Qto.
(too small, try deeper channel)
0.9 5.13 0.59 0.042 3.63 18.10 V<Vp, OK,
Q>Qin. OK
Now design for high retardance (class 13):
Try d -1.5 It and trial velocity, Vt - 3.0 fVsec
d (ft) A (ft) R (ft) Vt (fps) n V (fps) Q (cfs) Comments
1.5 11.25 0.90 3.0 0.08 2.5 reduce Vt
2.0 0.11 1.8 reduce Vt
1.6 0.12 1.6 18 Q>Qto OK
Channel summary:
Trapezoidal shape, Z-3, b-3 ft, d-1.5 ft. grade - 2%
8.059

0
Table 8.05a
Maximum Allowable Design Velocities'
for Vegetated Channels
Typical Soil Grass Lining
Channel Slope Characteristicsa
Permissible Velocity3
Application
for Established Grass
Lining (ft/sec)
0-5% Easi Erodible Bermuda rass
Non -plastic
%
a escue
(Sands & Silts) Bahiagrass
Kentucky bluegrass
4.5
Grass -legume mixture
3.5
Erosion Resistant Bermudagrass
Plastic
6.0
Tall fescue
(Clay mixes) Bahiagrass
5.5
5,5
Kentucky bluegrass
5.5
Grass -legume mixture
4.5
5-10% Easily Erodible Bermudagrass
Non -plastic Tall fescue
4.5
(Sands & Silts) Bahiagrass
4.0
4.0
Kentucky bluegrass
4.0
Grass -legume mixture
3.0
Erosion Resistant Bermudagrass
Plastic
5.5
Tall fescue
(Clay Mixes) Bahiagrass
5.0
5.0
Kentucky bluegrass
5.0
Grass -legume mixture
3.5
>10% Easily Erodible Bermudagrass
Non -plastic Tall fescue
3.5
(Sands & Silts) Bahiagrass
2.5
2.5
Kentucky bluegrass
2.5
Erosion Resistant Bermudagrass
Plastic Tall fescue
4.5
(Clay Mixes) Bahiagrass
3.5
3.5
Kentucky bluegrass
3.5
Source: USDA-SCS Modified
NOTE: 'Permissible Velocity based on 10-yr storm peak runoff
ZSoil
erodibility based on resistance to soil movement from concentrated flowing water.
3Before grass is established, permissible velocity is determined by the type of temporary liner used.
Selecting Channel To calculate the required size of an open channel, assume the design flow is
Cross -Section uniform and does not vary with time. Since
actual flow conditions change
throughout the length of a channel, subdivide the channel into design reaches,
Geometry and design
each reach to carry the appropriate capacity.
The three most, commonly used channel cross-section are "W-shaped, par-
abolic, and trapezoidal. Figure 8.05b gives mathematical formulas for the area,
hydraulic radius and top width of each of these shapes.
f
ti
8.05.4

a
BARRY J. SMALL
GENERAL MANAGER
OCEAN SIDE CORPORATION
REAL ESTATE DEVELOPERS
HWY. 179 IN CALABASH
P.O. BOX 4640
CALABASH, NORTH CAROLINA 28470
LOCAL TELEPHONE [phone]
N.C. 1-800-422-8092
OUTSIDE N.C. 1-800-443-4819
MASON H. ANDERSON
PRESIDENT
W.J. McLAMB, JR.
SECRETARY -TREASURER
RECEIVED
Ms. Linda Lewis FEB 22 1993
N.C. Division of Environmental Management
127 Cardinal Drive Extension
Wilmington, North Carolina 28405 Wilmington Regional Office
DEM
Subject: Restrictive Covenants Limiting "Built -Upon" Area
Stormwater Management Plan
Ocean Side Place
Brunswick County
Dear Ms. Lewis:
The following statements will be included in the Restrictive
Covenants for Ocean Side Place.
"No more than 2,450 square feet of any lot and no more than
5,200 square feet of the clubhouse area shall be covered by
structures and/or paved surfaces, including walkways or patios
of brick, stone, slate or similar materials.- This covenant
is intended to insure continued compliance with stormwater
runoff rules adopted by the State of North Carolina and,
therefore, benefits may be enforced by the State of North
Carolina." "Reserved area adjacent Lot 220 shall not be built upon."*
"No structures and/or paved surfaces, including walkways or
patios of brick, stone, slate or similar materials, shall be
placed within 30 feet of the mean high water line of surface
waters. This covenant is intended to insure continued compliance
with stormwater runoff rules adopted by the State of North
Carolina and, therefore, benefits may be enforced by the State
of North Carolina."
The following will be stated in the deed:
"This(these) covenant(s) is(are) to run with the land and shall
be binding to all parties and all persons claiming under them."
STORMWATER
MAP Z(o
fib-1993
SIGNA
Signa
Date:
*Without prior approval by M.' D,E.,M.
D E M
.0J 4 `I30z i'1

State of North Carolina
Department' of FnArolnrnent, Health, and Natural Resources
Wilmington Regional Office
James B. Hunt, Jr., Governor
Jonathan B. Howes, Secretary
March 5, 1993
DIVISION OF ENVIRONMENTAL MANAGEMENT
Mr. Joseph Hill Jr., P.E.
1602 Harbour Drive
Wilmington, North Carolina
Dear Mr. Hill:
28401
Subject: ADDITIONAL INFORMATION
Stormwater Project No. 930217
Ocean Forest West
Brunswick County
Bob Jamieson
Regional Manager
The Wilmington Regional Office received a partial Stormwater_Submittal for the Ocean Forest
West Subdivision on February 22, 1993, with the remainder of the submittal on March 4, 1993. A
preliminary review of that information has determined that the submittal for the subject project is not
complete. The following information is needed to continue the stormwater review:
1. Please provide velocity calculations for the main outlet swales (5:1 side slopes), to
verify that they will not erode.
2. The Restrictive Covenants, Operation and Maintenance Plan, and Density Limits Form
show the name of the subdivision as Ocean Side Place, but the plans show Ocean
Forest West. Please change these documents to indicate the correct name. (originals
returned).
3. What is the purpose of the reserved area behind lots 198, 199, 219, 220, 221, 224, 225
and 226? If any impervious surfaces- are proposed, please indicate in the calculations.
Also. please add to the deed restrictions a statement concerning the reserved area and
its impervious cover, allowed, or that it shall not be built on.
4. Preliminary calculations indicate that if no impervious cover is proposed for the
reserved area., the proposed deed restrictions will be adequate, and the project will
meet density.
-continued-
127 Cardinal Drive Extension, Wilmington, N.C. 28405-3845 • Telephone [phone] • Fax 919-35m004
An Equal Opportunity Affirmative Action Employer

Mr. Hill
March 5, 1993
Stormwater Project No. 930217
-----------------------------------------
Please note that this request for additional information is in response to a preliminary review.
The requested information should be received by this Office prior to April 5, 1993, or the submittal
will be returned as incomplete.
If you have any questions concerning this matter please feel free to call me at [phone].
DA/arl: 930217.MAR
cc: (2) Linda Lewis
Central Files
Sincerely,
Ms. Linda Lewis
Environmental Engineer
2

JOSEPH S. HH.L, JR. and ASSOCIATES
CONSULTING ENGINEERS and PLANNERS
1602 HARBOUR DRIVE
WILMINGTON, NORTH CAROLINA
TELEPHONE [phone]
r
March 3; 1993
MAILING ADDRESS:
POST OFFICE BOX 5592-STA. 1
WILMINGTON, N.C. 28403-4155
Ms. Linda Lewis JIM fiMQ� 4 1993
N.C. Division of Environmental Management STOK10 Yi
WATEL ,n
�
gtoo .o
127 Cardinal Drive Extension DEianar pff;�,
Wilmington,. North Carolina 28405 V. L
Subject: Ocean Forest West I ll
Stormwater Management Plan MAR C 4 1993
Brunswick County D E iVl
Dear Ms. Lewis: 9307,11
Enclosed are two (2) copies of the Grading, Erosion Control and
Stormwater Management Plan for Ocean Forest West.
The Erosion Control Plan was approved September 17, 1990. The
subdivision was not named at that time and approval was issued under the
name "Carter Tract/Unnamed Subdivision".
Plan: The following items are included as part of the Stormwater Management
1. Site plan indicating all built -upon surfaces.
2. Computations showing percentage of built -upon surfaces.
3. Copi-es of deed restrictions --and res4et ve covenants which
ThaSe�
bfdr+:t
Prr It VS•I — 4 - State i21� t of r en9464!i-
y es�"""' t-yfor aperati•en-anc# maintenance procedures.
13y ocegh S. fterettien and i ntenanee-M+anual-.
5.4e, copo. 6• ensity Limit Submittal Form.
Please review this plan as soon as poss.ib:le.
Please do not hesitate to contact me if you have any questions or need
additional information.
Sincerely,
JOSEPH S. HILL, JR. and ASSOCIATES
JSH/pat Jos. h.S. Hill, Jr., P.E.
attachments

OCEAN FOREST WEST
Stormwater Management Plan
Ocean Forest West is a single family home subdivision. This project is
located adjacent to an unnamed.tributary to Cawcaw Creek which is classified
C sw. The low density option for stormwater management allows a maximum of
30% impervious surface coverage for projects discharging to waters classified
other than SA.
Built -upon area will be 29.71%. Streets will be provided with asphalt
curbs and gutters. Runoff collected in gutters will be discharged through
asphalt flumes to roadside swales. Runoff from roadside swales will discharge
to perimeter ditches after passing through swale exit sections having a
minimum length of 100 feet and minimum side slopes of 5:1. Drop manholes will
be provided to dissipate the grade differential between exit swales and
existing perimeter ditches.
The attached plan and calculations show that this project complies with
N.C.D.E.M. stormwater management regulations.
STORMWKILK
LIB
U
MAR
0 4
1993
D E M
-�� g3OZl? __

0
OCEAN FOREST WEST
Stormwater Management Plan
Built -Upon Area Calculations
Street Pavement Calculations:
22' wide pavement x 10,805 LF (streets) = 237,710 Sq. Ft.
Radii at street intersections (34 x 200 Sq. Ft.) = 6,800 Sq. Ft.
Cul-de-sac - 3
Total Street Pavement
Built -Upon Area Calculations for Lots:
235 Lots x 2,450 Sq. Ft. = 575,750 Sq. Ft.
= 13,22 AC.
Built -Upon Area Calculations for Clubhouse:
Clubhouse Building and Amenities = 5,200 Sq. Ft.
= 0.12 AC.
Total Built -Upon Area = 19.04 AC.
Total Project Area = 64.09 AC.
19.04 i 64.09 = 29.71% Built -Upon Area
,850 Sq. Ft.
= 248,360 Sq. Ft.
= 5.70 AC.
STORMW Am"IFER
k 6 � 0 W t u l] V
MAR 0 4 1993
DEM
..----
Project Built -Upon Area is less than the 30% maximum allowed for projects
discharging to waters classified other than SA.

tio
BARRY J. SMALL
GENERAL MANAGER
OCEAN SIDE CORPORATION
REAL ESTATE DEVELOPERS
HWY. 179 IN CALABASH
P.O. BOX 4640
CALABASH, NORTH CAROLINA 28470
LOCAL TELEPHONE [phone]
N.C. 1-800-422-8092
OUTSIDE N.C. 1-800-443-4819
MASON H. ANDERSON
PRESIDENT
W.J. McLAMB, JR.
SECRETARY -TREASURER
RECEIVED
FEB 22 1993
Ms. Linda Lewis
North Carolina Division of Environmental Management Wilmington Regional Office
127 Cardinal Drive Extension DEM
Wilmington, North Carolina 28405
Subject: Statement of Responsibility
Stormwater System Operation and Maintenance
Ocean Side Place
Brunswick County
Dear Ms. Lewis:
This letter acknowledges that a Stormwater Management Plan has
been submitted on behalf of Ocean Side Place.
The Ocean Side Place Homeowner's Association will be responsible
for the operation and maintenance of the stormwater management system
as required by DEM and the operation and maintenance procedures
included as an integral part of the Stormwater Management Plan.
The Ocean Side Place Homeowner's Association will be responsible
for repairing or replacing any part of the stormwater management system
which may become inoperable.
cc: Joseph S. Hill, Jr. and Assoc.
Sincerely
H. Anderson
ent
STORMIAIATER1.9
FEB 2 2 1993
'ol a Q30M1'I