SW8940217_HISTORICAL FILE_19940316

STORMWATER DIVISION CODING SHEET
POST -CONSTRUCTION PERMITS
PERMIT NO.
SW8 Cj402m
DOC TYPE
❑ CURRENT PERMIT
❑ APPROVED PLANS
HISTORICAL FILE
❑ COMPLIANCE EVALUATION INSPECTION
DOC DATE
Iqq y o 31 '-p
YYYYMMDD

State of North Carolina
Department of Environment, Health, and Natur esources
'n on Regional Office
James B. Hunt, Jr., Governor DIVI OF NMENTAL MANAGE Bob Jamieson
Jonathan B. Howes, Secretary Regional Manager
M • h 16, 1994
Mr. Stephen Miller
Gulfstream DevelopmR t Group, In
801 Paoli Court
Wilmington, North Caro' 28409
bject: ERTIFICATION OF COMPLIANCE
with Stormwater Regulations
Stormwater Project No. SW8 940217
The Keys of Kure Beach
New Hanover County
Dear Mi. er:
This Ce ication is pursu to the application for The Keys of Kure Beach received on February
21, 1"s,
nal inform on received on March 10, 1994. Based on our review of the project
plans and we It determined that the The Keys of Kure Beach stormwater control system
complies with the Stormwater gulations set forth in Title 15A NCAC 2H.1003(i). The runoff will be
treated in a detention pond to achieve 90 % reduction in Total Suspended Solids.
Any modification f the plans submitted to and approved by this Office or further development
of this site regardless ofhe fact that the modification may be less than 1 acre, will require an additional
Stormwater SubmittaUpodification and approval prior to initiation of construction. Modifications include
but are not limited J, project name changes, transfer of ownership,. redesign of built -upon surfaces,
addition of built-u n surfaces, redesign or further subdivision of the project area.
This Ce ication shall be effective from the date of issuance until rescinded. The project shall
be coin tnrcted and maintained in accordance with the plans and specifications approved by the
Wilmington gional Office. This Certification does not supersede any other permit or approval. The
developer is sponsible for obtaining any and all permits and approvals necessary for the development
of this proj t. This could include the Division of Coastal Management under CAMA requirements, the
Division o vironmental Management under Wetland 401 Water Quality Certification and/or a Dredge
and Fill P t and/or a Sewer Extension/Collection Permit, U.S. Army Corps of Engineers 404 Wetland
Permit, DES Stormwater Permit if disturbing five acres or more, local County or Town Agency
permits under their local ordinances, or others that may be required.
127 Cardinal Drive Extension, Wilmington, N.C. 28405-3845 • Telephone [phone] • Pax 910-350-2004
An Equal Opportunity A15ruutive Action Employer

I

Mr. Miller
March 16, 1994
Stormwater Project No. SW8 940217
A professional engineer must certify that the stormwater system has been installed in accordance
with the approved plans and specifications upon completion of construction. The attached certification
should be received by this Office within 30 days of completion of construction.
'11
If you have any questions concerning this matter, please call Ms. Linda Lewis or me at (910) 395-
Sincerely,
ave Adkins
Water Quality Supervisor
DA/arl: S:\WQS\STORMWAT\CERTIFIC\940217.MAR
cc: Mr. Joseph S. Hill
Mr. Sky Conklin, New Hanover County Inspections
Bradley Bennett
Linda Lewis
Wilmington Regional Office
Central Files

DIVISION OF ENVIRONMENTAL MANAGEMENT
PROJECT DATA
Project Name:
Project Number:
Location:
Applicant:
Mailing Address:
Submittal Date:
Water Body Receiving Stormwater Runoff:
Classification of Water Body:
If Class SA, chloride sampling results:
Pond Depth:
Permanent Pool Elevation:
Total Impervious Surfaces Allowed:
Offsite Area entering Pond:
Green Area entering Pond:
Required Surface Area:
Provided Surface Area:
Provided Storage Volume:
Temporary Storage Elevation:
Controlling Orifice Type/Diameter:
The Keys of Kure Beach
SW8 940217
New Hanover County
Mr. Stephen Miller
Gulfstream Development Group, Inc.
801 Paoli Court
Wilmington, North Carolina 28409
February 21, 1994
UT Cape Fear River
"SC"
U11
4.0 feet
14.4 MSL
284,725 square feet
N/A
397,425 square feet
24,824 square feet
58,600 square feet
29,768 cubic feet
14.9 MSL
2.5" pipe

1.
2.
3.
4.
5.
6.
WET DETENTION POND EVALUATION
Yes No The design storage is for the runoff from all impervious surfaces resulting from
1-inch of rainfall and is located above the permanent pool.
Yes No The permanent pool is designed for 90% total suspended solid (TSS) removal.
Therefore, no vegetative filter is required.
Yes No The runoff completely draws down to the permanent pool in 5 days, but not less
than 2 days.
Yes No The mean depth of the permanent pool is a minimum of 3 feet.
Yes No The inlet structure is designed to minimize turbulence and short circuiting.
Yes No An appropriate operation and maintenance plan has been provided for the
system.
7. Yes No THIS PROJECT MEETS THE STORMWATER CONTROL REQUIREMENTS
OF 15A NCAC 2H.1003 (g), (i), (k), and (1) (For Yes, 1 through 7 must all
be highlighted Yes.)
Brief Explanation: This detention pond is designed to remove 90% total suspended solids without the
aide of a vegetative filter.
DIVISION OF ENVIRONMENTAL MANAGEMENT SIGN -OFF
Wilmington Regional Office
Date Individual Evaluating Form/Plans
Date RE ' nal Water Quality Supervisor
cc: Applicant/Bradley Bennett/arl/WiRO/CF

DIVISI4` 'OF ENVIRONMENTAL MANAGENV NT
DENSITY ENGINEERED—.
PROJECT DATA
Project Name The Keys of Kure Beach
Location (County, Township/Municipality, Address, State Road) Kure Beach
Owner's Name Gulf Stream Development Group, Incorporated
Mailing Address
801 Paoli Court, Wilmington, N.C. 28409
Phone Number [phone] Submittal Date Jan. 25, 1994
Brief Description (include map and appropriate drawings) Project consists of 100 townhouses
on 15.66 acres with wet detention pond for stormwater management.
Name of Water Body Receiving Stormwater Runoff U: T. Cape Fear River
Classification of Water Body SC If SA waters, engineered system, and distance is <0.5
miles, attach report of chloride sampling results mg/1
State/Federal Permits/Approvals Required (Check appropriate blanks)
CAMA Major Sedimentation/Erosion Control X
404 Permit DEM/DHS Sewage Disposal
Other (Specify)
CALCULATION OF BUILT UPON AREA
Built upon area means that portion of a development that is covered by impervious or partially pervious cover
including buildings, pavement, recreation facilities, gravel, etc., but not including wood decking. If the project
includes areas draining to differentwater classifications, please note them separately below.
Subwatershed Subwatershed
Classification' SC
Built upon area 6: 54 AC
Total Project Area 15.66 AC
% Built upon Area 41.87
Allowable B/U Area --- 70-7
Is the Project B/U;Area' S',the Allowable B/U Area? No (If no, an engineers
% Built upon area ='(liuilt upon area / total project area) * 100
Built upon area limits for projects to meet density: SA waters — 25%, Other —30%
STORMWATER COLLECTION SYSTEM
Describe how the runoff will be treated runoff will be collected and
e.nrad in a wet detention pond
is
Office use only
TO�,'wlPVIT
lu)ltUL ��l5�ji.
IIJnU� FEB 2 1 1994 U
D E M
nT 46tv$ e46Z1%__

BUFFER AREA
Is the built upon area at least 30 feet from mean high water of all surface waters? Yes If no, please
provide a description
(Note: Only boat ramps, public roads, public bridges, and walkways to water related facilities are allowed
within 30 feet of the mean high water line if the project is intended to meet stormwater control
requirements through density limits.)
DEED RESTRICTIONS AND PROTECTIVE COVENANTS
By my signature below, I certify that the recorded deed restrictions and protective covenants for this project
shall limit the allowable built -upon area 001XY& to 284,725 square feet inclusive of right-of-way,
structures, pavement, walkways or patios of brick, stone, or slate, not including wood decking, state that
the covenants will be binding on all parties and persons claiming under them, that they will run with the
land, and that benefits may be enforced by the State of North Carolina, therefore, the covenant cannot be
changed or deleted without consent of the State.
CERTIFICATION
I, Stephen Miller , certify that the information included on this
submittal form is correct, that the project will be constructed in conformance with this information, and
that to the best of my knowledge, the proposed project complies with the requirements of 15 NCAC
2H.1003 (b). I authorize the below named person or firm to submit stormwater plans on my behalf, and
agree to abide by the deed restriction stateffient above.
Owner's Signature Date
Provide authorized person or firm name and address below:
Hr. _J'o�ePh 1-h ll, PE
I(oo2 42 LYpUw Or.
UiiIrn'ncJiOn A)G Z94-Ul
I, 15, CAJJn-� ,allotary Public for the State of �org CiAmo�,Jn
County of t.) Iha,.,. , do hereby certify that S4ol,e) lam: IlLi personally
appeared before me this q day of fc/n sn 19 and acknowledyh����Trdue execution
of the ifegoing instrument. Witness my hand and official seal, ,���Sp B. ry+'4'�.,��
Q l,,
My commission expires X, zA f ' rr"" 1 A ci
DIVISION OF ENVIRONMENTAL MANAGEMENT
TE
Regional Office
Y(o MA2 94-
Date,
- NI /agyc 14 r�J�W
Date
cc: Applicani]WiRO/Bradley Bennett/Central Files

4 FEB 21 1994
FINANCIAL RESPONSIBILITY/OWNERSHIP FORM
SEDIMENTATION POLLUTION CONTROL ACT LAND
-No person may initiate any land -disturbing activity on one or more contiguous acres as covered by the7 Act
before this form and an acceptable erosion and sedimentation control plan have been completed and approved
by the Land Quality Section, N.C. Department of Environment, Health, and Natural Resources. (Please type or
print and, if question is not applicable, place N/A in the blank.)
Part A.
1. Project Name The Keys of Kure Beach
2. Location of land -disturbing activity: County New Hanover City
or Township Kure Beach and Highway / Street Kure Village Way
3. Approximate date land -disturbing activity will be commenced: February 28
4. Purpose of development (residential, commercial, industrial, etc.) : Residential
5. Total acreage disturbed or uncovered (including oft -site borrow and waste areas)
15.66 AC
6. Amount of fee enclosed $ 330.00
7. Has an erosion and sedimentation control plan been filed ? Yes X No
8. Person to contact should sediment control issues arise during land -disturbing activity.
Name Stephen Miller Telephone [phone]
9. Landowner (s) of Record ( Use blank page to list additional owners.):
Gulf Stream Development Group- Inc, -
Name (s)
801 Paoli Court
Current Mailing Address
Wilmington N.C. 28409
City State Zip
Current Street Address
City State Zip
1625 Pa eNo. 1383 ,
10. Recorded in Deed Book No. 9 p fl �p
Part B. N � �."�°��R
1. Person (s) or firms (s) who are financially responsible forthis land -disturbing activity (Use the blank page to list
additional persons or firms):
Steohen Miller
Name of Person (s)or Finn (s)
801 Paoli Court
Mailing Address
Wilmington N C 28409
City State' - Zip .
Telephone [phone]
FEB 2 1 1994
Street Address ,n1 , ,y(N0: c�%
City State Zip
Telephone

2. (a) If the Financially Responsible Party is a Corporation give name and street address of the Registered
Agent.
Bob Weinbach
Name
801 Paoli Court
Mailing Address
Wilmington NC 28409
City State Zip
[phone]
Telephone
Street Address
City
Telephone
State Zip
(b) If the Financially Responsible Party is a Partnership give the name and street address of each General
Partner ( Use blank page to list additional oartners.):
Name
Mailing Address
Street Address
City State Zip City State Zip
Telephone Telephone
The above information is true and correct to the best of my knowledge and belief and was provided by me
under oath. ( This form must be signed by the financially responsible person if an individual or his attorney -in -
fact or if not an individual by an officer, director, partner, or registered agent with authority to execute instru-
ments for the finanacially responsible person ). I agree to provide corrected information should there be any
change in the information provided herein.
Bob Weinbach
Type or print name
Signa ure
President
Title or Authority
zly�9s�
Date
I, a Notary Public of the County of 44-1 do '
State of North Carolina, hereby certify that /fie 6 e". 't -ll
appeared'personally before me this day and being duly sworn acknowledged that the above form was exe-
cuted by,t�m,,,C t�,
��FQC��,`\`.•••••...�, tpess my hand and notarial seal, this y of fe��ab �5 19 5
-=
a� • --
Z� "•' c$ei Notary
My commission expires

JOSEPH S. HILL, JPL AND ASSOCIATES
CONSULTING ENGINEERS and PLANNERS
MAI II NC ADDRESS,
POSE OFFICE ROx 5592SEA1
pn�GCUy !.}NGTON. NC 2-0MIN155
"
IM2 HARBOUR DRIVE
MI INGWN, NORFN CAROUNA
I EPIIONE910.7"-15"
March 9, 1994
Ms. Linda Lewis
N. C. D. E. H. N. R.
127 Cardinal Drive Extension
Wilmington, North Carolina 28405-3845
Subject: Submittal of Additional Information
Stormwater Project No. SW8 940217
The Keys of Kure Beach
New Hanover County
Dear Ms. Lewis:
UI Lti 6 Ls � U L� bu
MAR 1 0 1994
R IEE IV]
T 7r
Iffifflffl__91V291
MAR 1 a 1994
Enclosed are three (3) sets of revised plans and calculations for the
Stormwater Plan for The Keys of Kure Beach.
The following items have been addressed and are included in this
submittal:
The name, address, and telephone number of the responsible party
are typed on the Operation and Maintenance Plan. The 0&M Plan
is notarized.
2. The detention pond surface area provided is based on the permanent
pool elevation of 14,4'. The calculations show the surface area
provided both at the permanent pool elevation and at the storage
pool elevation. The total volume of the pond at the storage contour
(14.9') is shown in the calculations.
3. The orifice invert elevation is shown to be 14.4'.
4. As we discussed, Club Drive is an existing public street with
existing storm drainage facilities. All project runoff beginning
at the back of the curb along Club Drive will be routed to the
stormwater pond by diversion through swales and storm sewer piping
as shown on the plans.
5. The actual building footprint is 5,640 square feet. With an
allowance of 160 square feet for sidewalks, the total built —upon
area for each building will be 5,800 square feet. The calculations
have been corrected to show a building area of 5,800 square feet
(building detail enclosed).

Ms. Linda Lewis
The Keys of Kure Beach
March 9, 1994
Page 2
6. A note has been added to the erosion control notes to require
removal of sediment from the sediment storage zone of the pond.
Please review this information as soon as possible.
Please do not hesitate to contact me if you have any questions.
Sincerely,
JOSEPH S. •HII.LaL,o JR. and ASSOCIATES
QI�f"'^
JSH/pat Josep S. Hill, Jr., P.E.
enclosures

THE KEYS OF KURE BEACH
Stormwater Detention Pond Calculations
Revised 3/9/94
Stormwater runoff from the project will be retained in wet detention
pond. This pond will store the runoff generated by 1 inch of rainfall.
The stored runoff will be discharged over a period of 4.4 days.
The pond area required to remove 90% of total suspended solids was
calculated using the SA/DA Percentage Chart (see chart) for North Carolina
coastal regions.
ff Calculations
Impervious Surfaces: 25 — Buildings @ 5,800 Sq. Ft. Each
= 145,000
Sq.
Ft.
Streets and Driveways
= 130,950
Sq.
Ft.
Pool (including parking and walks)
= 8,775
Sq.
Ft.
Total Impervious Area
= 284,725
Sq.
Ft.
= 6.54 AC.
Pervious Surfaces (Grassed, Landscaped areas) = 397,425 Ac.
9.12 Ac.
fk�
L) Li
V
MAR 1 'C 1994
DEm
�UZ17
284,725 x 0.083' Runoff = 23,632 CF
397,425 x 0.083' Runoff x 0.2 (R.O. Coefficient) = 6,597 CF
Total Runoff (1" Rainfall) = 30,229 CF
= 226,113 Gallons
Pond Surface area @ Storage Pool Elev. of
14.9'
= 62,000
Sq.
Ft.
Pond Surface area @ Permanent Pool Elev. of
14.4'
= 59,050
Sq.
Ft.
Average Pond Surface
Area
= 60,525
Sq.
Ft.

I
The Keys of Kure Beach
Stormwater Calculations
Page 2
Pond Storage Volume = 0.5' depth x 60,525 Sq. Ft. = 30,262 CF
= 226,360 Gallons
Solids Settling Area Calculations
Total watershed area = 15.66 Ac.
Impervious % = 6.54 Ac. o- 15.66 Ac.
= 41.8%
Basin Mean Depth = 4.0'
SA/DA % required for 90% solids removal (see chart) = 3.6%
3.6% x 15.66 Ac. = 0.56 Ac.
Basin Surface area @ Permanent Pool elev. of 14.4' = 1.36 Ac.
Basin is therefore adequate for 90% TSS removal.
S. d
,,.,....
VA ,_..
O
S� SEAL r�
8982
✓ ...
'O GIN .;
KEYSTWTR 3l9 /V

20%
30%
40%
50 %
60%
70%
80%
90%
100%
THE KEYS
SA/DA - 85%.TSS REMOVAL WITH 30' VEGETATIVE FILTER
3.OFT 3.5FT 4.OFT 4.5FT 5.OFT 5.5FT 6.OFT 6.5FT 7.OFT 7.5FT
.9
.8
.7
.6
.5
1.7
1.3
1.2
1.1
1,0
.9
.8
.7
".6
_ .5 .
2.5
2.2
1.9
.1.8
1.6
1.5
1.3
1.2
.1.0
.9
3.4
3.0
2.6
2.4
2.1
1.9
1.6
1.4
1.1
1.0 .
4.2
3.7
3.3
3.0
2..7
2.4
2.1
1.8
1.5
1.3
5.0
4.5
3.8
3.5
3.2
2.9
2.6
2.3
2.0
1.6
6.0
5.2
4.5
4.1-
3.7
3.1
2.9
2.5
2.1
1.8
6.8
6.0
5.2
4.7
4.2
3.7
3.2
2.7
2.2
2.0
7.5
6.5
5.8
5.3
4.8
4.3
3.8
3.3
2.8
1.3
8.2
7.4
6.8
6.2
5.6
5.0
4.4
3.8
3.2
2.6
SA/DA - > 90% TSS REMOVAL
WET DETENTION WITHOUT VEGETATIVE FILTER
IMPERA 3.OFT 3.5FT14.OFT14.5FT
10%
1.3
1.0
-8-
.7
20%
2.4
2.0
1.8
1.7
30%
3.5
3.0
2.7
2.5
4�E7 40%
4.5
4.0
3.5
36.3.9
3.1
50%
5.6
5.0
4.3
60%
7.0
6.0
5.3
4.8
70%
8.1
7.0
6.0
5.5
80%
9.4
8.0
7.0
6.4
90%
10.7
9:0
7.9
7.2
100%
12.0
10.0
8.8
8.1
OFT 5.5FT 6.OFT 6.5FT
.6
.5
.4
.3
1.5
1.4
1.2
1.0
2.2
1.9
1.6
1.3
2.8
2.5
2.1
1.8
3.5
3.1
2.7
2.3
4.3
3.9
3.4
2.9
5.0
4.5
3:9
3.4
5.7
5.2
4.6
4.0
6.5
5.9
5.2
4.6
7.3
6.6
5.8
5.1
.9 .6
1.1 .8
1.4 1.1
1.9 1.5
2.4 1.9
2.9 2.3
3.4 2.8
3.9 3.3
4.3 3.6

ORIFICE DISCHARGE RATE CALCULATIONS
Use 2 1" diameter orifice for outlet.
Calculate average discharge rate and time to lower orifice head from 0.50'
to 0.45':
0.05' pond height x 60,984 Sq. ft. pond area (@ mean storage elev.)
x 7.48 gal/ft3 = 22,808 Gallon Storage
Average head on orifice from 0.50' to 0.45' = 0.475'
Average discharge rate @ 0.475' head:
Q(GPM) = (449)c A 2gh
Q(GPM) = Volume discharged in gallons per minute
c = discharge coefficient = 0.6
A = orifice area in square feet
g = gravity = 32.2
h = head above center of orifice
Q(GPM) = (449)(.6)(.0341) (2)(32.2)(0.475)
Q = 50.8 GPM
Time required to lower pond 0.1' @ 0.475' average head:
T = 22,808 Gal. - 50.8 GPM = 449 minutes
50.8 minutes vs 449 minutes plotted on curve (See Discharge Curve).
Discharge rate and time to lower head from 0.45' to 0.40'
Q = 48.1 GPM
T = 22,808 Gal. r 48.1' GPM = 474 minutes
48.1 GPM vs 923 minutes plotted on curve.
Keys —St 4

Discharge rate and time to lower head from 0.40' to 0.35':
Q = 45.1 GPM
T = 22,808 Gal. o--45.1 GPM = 506 minutes
45.1 GPM vs 1429 minutes plotted on curve.
Discharge rate and time to lower head from 0.35''to 0.30':
Q = 42.0 GPM
T = 22,808 Gal. o- 42.0 GPM = 543 minutes
42.0 GPM vs 1972 minutes plotted on curve.
Discharge rate and time to lower head from 0.30' to 0.25':
Q = 38.7 GPM
T = 22,808 Gal. r 38.7 GPM = 590 minutes
38.7' GPM vs 2,562 minutes plotted on curve.
Discharge rate and time to lower head from 0.25' to 0.20':
Q = 35.0 GPM
T = 22,808 Gal, o- 35.0 GPM = 652 minutes
35.0 GPM vs 3,214 minutes plotted on curve.
Discharge rate and time to lower head from 0.20' to 0.15':
Q = 30.8 GPM
T = 22,808 Gal. = 30.8 GPM = 740 minutes
30.8 GPM vs 3,954 minutes plotted on curve.
Discharge rate and time to lower head from 0.15' to 0.10':
Q = 26.1 GPM
T = 22,808 Gal. o- 26.1 GPM '= 873 minutes
26.1 GPM vs 4,827 minutes plotted on curve.
Keys —St 5

Discharge rate and time to lower head from 0.10' to 0.05':
i
Q = 20.2 GPM
T = 22,808 Gal. o- 20:2 GPM = 1,129 minutes
20.2 GPM vs 5,956 minutes plotted on curve.
Discharge rate and time to lower head from 0.05' to 0.00':
Q = 11.7 GPM
T = 22,808 Gal. !- 11.7 GPM =.1949 minutes
11.7 GPM vs 7905 minutes plotted on curve.
The outlet structure will discharge the total calculated runoff volume of
226,113 gallons in approximately 4.4 days (See Orifice Discharge Curve).
Keys —St 6

70
60
50
40
H
30
20
THE KEYS
57-0RblV1AT`R P 0IVI)
ORIFICE DISCHARGE
S0.s r-pm/44q
MIN.'
48.IGPM/g23
MIN,
451 GPr?/ 41.q MIN
VV-
Y 38.7
GPM 562 lilt(•
��
2.5"o ORIFICE WILL
DISCHARGE CALCULRTED
14-MIi`1•
RUWOP'EV06vl+'rE OF
�35.0GPAl/
226�II3 GALS. fh"
N,P141373 MI
-} 4 DAYS
�361.PG
6.1 GPAV .427 111N.
�2
20,2CYM/S,956
MIN.
11.7GPM/7g05 MIN.
DAY I
DAYI
DAY? I UAY
DAY 5
71,700 GALS,
5B 500 GALS, 4R 3DD rrALS :/ILS.
26,400 GALS.
O ?00
20:00 30'00.
1000 5000
6'0
,00 7P0,0.
860 9000

�q
0
THE KEYS OF KURE BEACH
STORMWATER MANAGEMENjPL
January 1994
Sf1V'w°-%TER
/u �� L�uu� If
FEB 2 1
1994
OT # 5 D- �4 zn
S.f�kl_�
Ey SEAL rsj
8932
iOJ GINE�J
S
1102 019V
Prepared By:
JOSEPH S. HILL, JR. and ASSOCIATES
CONSULTING ENGINEERS and PLANNERS
1602 Harbour Drive
Wilmington, N.C. 28401
[phone]

u
0
THE KEYS OF KURE BEACH
Stormwater Detention Pond Calculations
Stormwater runoff from the project will be retained in wet detention
pond. This pond will store the runoff generated by 1 inch of rainfall.
The stored runoff will be discharged over a period of 4.4 days.
The pond area required to remove 90% of total suspended solids was
calculated using the SA/DA Percentage Chart (see chart) for North Carolina
coastal regions.
Runoff Calculations
534$ 14-7 450
Impervious Surfaces: 125 = Bui'ld'ngs_@_2500_Sq._Ft.—Each—=-1.45,000—Sq.—Ft.2 (DZ SOO
Streets and Driveways = 130,950 Sq.. Ft.
Pool (including parking and walks) = 8,775 Sq. Ft.
Total Impervious Area = 284,725 Sq. Ft.
= 6.54 AC.
Pervious Surfaces (Grassed, Landscaped areas) = 397,425 Ac.
= 9.12 Ac.
284,725 x 0.083' Runoff = 23,632 CF
397,425 x 0.083' Runoff x 0.2 (R.O. Coefficient) = 6,597 CF
Total Runoff (1" Rainfall) = 30,229 CF
= 226,113 Gallons
(Surface --areaof—detention pond at --mean elevation of-1'4-65')
60,984 Sq.Ft.
in
30,229 CF i- 60,984 Sq. Ft. = 0.5' Storage Depth Required.
% erdr �p / � (p S
Keys —St 2

n
Solids Settling Area Calculations
Total watershed area = 15.66 AC.
Impervious % = 6.54 AC a 15.66 AC.
= 41.8%
CBasin Mean Depth 4.0� Ac k,t,O� 31 is I' 5ec�k-""'+ XEa-
SA/DA% required for 90% solids removal (see chart) = 3.6%
3.6% x 15.66 AC = 0.56 AC.
Basin Surface area @ mean storage elev. of 14.65' = 1.40 Ac.
Basin is therefore adequate for 90% TSS removal.
Keys -St 3

SA/DA
- 85%:TSS
REMOVAL
WITH
30' VEGETATIVE FILTER
IMPER.%
3.OFT
3.5FT
4.OFT
4.5FT
5.OFT
5.5FT
6.OFT
6.5FT
7.OFT
7.5FT
10%
.9
.8
.7
.6
.5
20%
1.7
1.3
1.2
1.1
1.0
.9
.8
.7
.6
.5
30%
2.5
2.2
1.9
1.8
1.6
1.5
1.3
1.2
1.0
.9
40%
3.4
3.0
2.6
2.4
2.1
1.9
1.6
1.4
1.1
1.0
50%
4.2
3.7
3.3
3.0
2.7
2.4
2.1
1.8
1.5
1.3
60%
5.0
4.5
3.8
3.5
3.2
2.9
2.6
2.3
2.0
1.6
70%
6.0
5.2
4.5
4.1.
3.7
3.1
2.9
2.5
2.1
1.8
80%
6.8
6.0
5.2
4.7
4.2
3.7
3.2
2.7
2.2
2.0
90%
7.5
6.5
5.8
5.3
4.8
4.3
3.8
3.3
2.8
1.3
100%
8.2
7.4
6.8
6.2
5.6
5.0
4.4
3.8
3.2
2.6
THE KEYS
SA/DA - > 90$ TSS REMOVAL
FOR WET DETENTION WITHOUT VEGETATIVE FILTER
IMPER.$ 3.OFT 3.5FT 4.OFT 4.5FT S OFT 5.5FT 6.OFT 6.5FT 7.OFT 7.5FT
10%
1.3
1.0
.7
.6
.5
.4
.3
.2
.1
20%
2.4
2.0
1.8
1.7
1.5
1.4
1.2
1.0
.9
.6
30%
3.5
3.0
2.7
2.5
2.2
1.9
1.6
1.3
1.1
.8
4177 40%
4.5
4.0
3.5
3'63.9
3.1
2.8
2.5
2.1
1.8
1.4
1.1
50%
5.6
5.0
4.3
3.5
3.1
2.7
2.3
1.9
1.5
60%
7.0
6.0
5.3
4.8
4.3
3.9
3.4
2.9
2..4
1.9
70%
8.1
7.0
6.0
5.5
5.0
4.5
3.9
3.4
2.9
2.3
80%
9.4
8.0
7.0
6.4
5.7
5.2
4.6
4.0
3.4
2.8
90%
10.7
9:0
7.9
7.2
6.5
5.9
5.2
4.6
3.9
3.3
100%
12.0
10.0
8.8
8.1
7.3
6.6
5.8
5.1
4.3
3.6

0
ORIFICE DISCHARGE RATE CALCULATIONS
Use 2 z"' diameter orifice for outlet.
Calculate average discharge rate and time to lower orifice head from 0.50'
to 0.45':
0.05' pond height x 60,984 Sq. ft. pond area (@ mean storage elev.)
x 7.48 gal/ft3 = 22,808 Gallon Storage
Average head on orifice from 0.50' to 0.45' = 0.475'
Average discharge rate @ 0.475' head:
Q(GPM) = (449)c A 2gh
Y
Q(GPM) = .Volume discharged in gallons per minute
c = discharge coefficient = 0.6
A = orifice area in square feet
g = gravity = 32.2
h = head above center of orifice
Q(GPM) = (449)(.6)(.0341) (2)(32.2)(0.475)
Q = 50.8 GPM
Time required to lower pond 0.1' @ 0.475' average head:
T = 22,808 Gal. o- 50.8 GPM = 449 minutes
50.8 minutes vs 449 minutes plotted on curve (See Discharge Curve).
Discharge rate and time to lower head from 0.45' to 0.40':
Q = 48.1 GPM
T = 22,808 Gal. r 48.1' GPM = 474 minutes
48.1 GPM vs 923 minutes plotted on curve.
Keys —St 4

Discharge rate and time to lower head from 0.40' to 0.35':
Q = 45.1 GPM
T = 22,808 Gal. r.45.1 GPM = 506 minutes
45.1 GPM vs 1429 minutes plotted on curve.
Discharge rate and time to lower head from 0.35' to 0.30':
Q = 42.0 GPM
T = 22,808 Gal. f 42.0 GPM = 543 minutes
42.0 GPM vs 1972 minutes plotted on curve.
Discharge rate and time to lower head from 0.30' to 0.25':
Q = 38.7 GPM
T = 22,808 Gal. r 38.7 GPM = 590 minutes
38.7' GPM vs 2,562 minutes plotted on curve.
Discharge rate and time to lower head from 0.25' to 0.20':
Q = 35.0 GPM
T = 22,808 Gal. o- 35.0 GPM = 652 minutes
35.0 GPM vs 3,214 minutes plotted on curve.
Discharge rate and time to lower head from 0.20' to 0.15':
Q = 30.8 GPM
T = 22,808 Gal. = 30.8 GPM = 740 minutes
30.8 GPM vs 3,954 minutes plotted on curve.
Discharge rate and time to lower head from 0.15' to 0.10':
Q = 26.1 GPM
T = 22,808 Gal. t 26.1 GPM '= 873 minutes
26.1 GPM vs 4,827 minutes plotted on curve.
Keys —St 5

Discharge rate and time to lower head from 0.10' to 0.05':
Q = 20.2 GPM
T = 22,808 Gal. r 20.2 GPM = 1,129 minutes
20.2 GPM vs 5,956 minutes plotted on curve.
Discharge rate and time to lower head from 0.05' to 0.00':
Q = 11.7 GPM
T = 22,808 Gal. r 11.7 GPM = 1949 minutes
11.7 GPM vs 7905 minutes plotted on curve.
The outlet structure will discharge the total calculated runoff volume of
226,113 gallons in approximately 4.4 days (See Orifice Discharge Curve).
Keys —St 6

70
THE KEY5
5r0Rf1b•1ATE S POND
ORIFICE DISCHARGE
60
50.BGPf7/449 MIN.;
i I
i
48•IGPM/923 MIN,
°O 45.1 GPM/I429 MIN.
r;t,O CrPM f 177 2 14; P,-
y 38.7 GPAI'1 562. (YIP; 2,5"{!i ORIFICE WILL
DISCHARGE CALCULRTED
40 RUfJO! F, VOLJ1irE OF
\ S35•0GPId11214• MIN. 226�1'13 GALS, (A'
CL:w z
e�-
1' 30.?GP1e�1R5'4 MIN
v
30 �2 L.1 GPAV; 927 HIN.
2o,2FPM/5956 MIN.
20-
LI'�,7GPM/790'SM/N.
I
L'
i
DAY 1 DAY 2 DAY 3 DAY + DAY 5
71,700 GALS, 5B,500 GALS, 4 E?,300 rAL 5 I u, 'o;) 6:AL5. 26,400 GALS.
0 0'00 2000 3600 40;00 000 6'000 700,0. BOiO,b 90;o0

State of North Carolina
Department of Environment, Health, and Natural Resources
Wilmington Regional Office
James B. Hunt, Jr., Governor DIVISION OF ENVIRONMENTAL MANAGEMENT Bob Jamieson
Jonathan B. Howes, Secretary Regional Manager
March 1, 1994
Mr. Joseph S. Hill, P.E.
Joseph S. Hill and Associates
1602 Harbour Drive
Wilmington, North Carolina 28401
Subject: ADDITIONAL INFORMATION
Stormwater Project No. SW8 940217
The Keys at Kure Beach
New Hanover County
Dear Mr. Hill:
The Wilmington Regional Office received a Stormwater Submittal for the The Keys at Kure Beach
on February 21, 1994. 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 print or type the name, address, and phone number of the responsible party on the
Operation and Maintenance Plan. The O & M Plan must be notarized by a notary public,
not witnessed.
2. The surface area provided must be based on the surface area at the permanent pool of 14.4,
not the mean pool of 14.65. I am unfamiliar with the term mean pool elevation. This
Office requires only a permanent pool and a storage pool elevation. The calculations also
do not address the surface area and volume provided at the storage contour (14.9) for the
1" volume; they only address the required volume.
3. Three (3) sets of plans are required for all first time submittals and subsequent
revisions.
4. If you place the center of the orifice at 14.4, then the water will actually draw down to
14.3 based on a 2.5" orifice. Please revise the detail to indicate that the invert of the
orifice is 14.4.
127 Cardinal Drive Extension, Wilmington, N.C. 28405-3845 • Telephone [phone] • Fax [phone]
An Equal Opportunity Affirmative Action Employer

_r
Mr. Hill
March 1, 1994
Stormwater Project No. SW8 940217
5. Has the off -site runoff on Kure Village Way been accounted for or routed around the pond?
How will the runoff on Club Drive reach the pond? It appears that an existing piped system
is collecting that runoff ancj�transporting it to the existing 30" CMP at the west end of Club
Drive. W PaCi 5 i��
6. Please provide a standard building dimension detail. My calculation of building area is
5,898 square feet per building, not 2,500 as you indicate. Please revise your calculations
to reflect the actual building footprint - (2,500 x 25 = 62,500 not 145,000). My calculation
of total impervious area is approximately 4,000 square feet more than yours. Providing
the building detail should clear up the difference.
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 1, 1994, or the submittal will be
returned as incomplete.
If you have any questions concerning this matter please feel free to call me at [phone].
1. 41d, ndq- 5{Ur2ye..
(J Sincerely, v
Ms. Linda Lewis
Environmental Engineer
DA/arl: S:\WQS\STORMWAnADDINFO\940217.MAR
cc: (2) Linda Lewis
Central Files

JOSEPH S. HILL, JR AND ASSOCIATES
CONSULTING ENGINEERS and PLANNERS
IW2 HARBOUR DRIVE
W INGWN, NORM CAROIINA
TTlEPHONE910.99A15"
Fdbr,uary 211, 1994
Ms. Linda Lewis
N.C.D.E.M.
127 Cardinal Drive Extension
Wilmington, North Carolina 28405
Subject: The Keys of. Kure Beach
Stormwater Management Plan
New Hanover County
Dear Ms. Lewis:
MAILNGADDnccG
POST OT}mC BOX 559LSTA.1
WIU&NGTON, NC ]8 155
I
a��seIra V R
% 4z" V r
Ff B 211994 U
Enclosed are two (2) copies of the stormwater management plan for The
Keys of, Kure Beach.
This project is a townhouse development. It is located adjacent to
an existing drainage ditch discharging to the Cape Fear River, which is
classified SC. The project built —upon area is calculated to be 41.7%. Storm
drainage piping, catch basins, and asphalt curbing will be used to collect
and channel runoff. Therefore, a wet detention pond will be constructed
to treat stormwater prior to discharge.
The following items are included:
1. Site plan indicating built —upon surfaces. (2 copies)
2. Computations showing percentage of built —upon surfaces. (2 copies)
3. Completed and signed stormwater submittal form, (original)
Please review this plan .as soon as possible. Copies of the plan have
also been sent to the New Hanover County Engineering Department for their
review with regards to erosion control.
Pleaseludo noit hes�ita.te to contact me if you have any questions or need
additional i�flo.g`S`Iww'?9 �E
iii,
FEB 2 1 1994
OEM
nT #Scl4oZf7
JSH/pat
cc: Mr. Jim Craig
Sincerely,
JOSEPH S. HILL, JR. and ASSOCIATES
9"Y
!JQ
Joseph S. Hill, Jr., P.E.

2
The Iles of Kure Poeeob
5w's g4-oZ7
lease or /-4/ve n2me-j
2 dress " pha� e 4r- o-f re spa s; 1 le Per
Imo, musf be noior',-zed b �a �f
(Ju�'J�iGr ✓)C>�" WI I Y12SSeC�.
II
y �l
90 % T55' Z
2,
CaIGS o10 rnof- prove% a checla Fcr 5hya-- je C2ff _
Cl i
5�1� or ,elevzho� Fes. ProfJose� 1ii -runoff.
T 4.
F/o?5 CoIC 5 017cl da Civf m olch
- 5 5 ce 5- 5 bw SA b2secl o�
1-2 r✓I O—f Ci'l fYe l4. -T-( C2/17"eK r s ac PC
/7(.Zo83�
14, 3' �
c/ue5 mean of elevoe'=m5Z
_
SPeor ,& 3 s s oll clef�i

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r

THE KEYS OF KURE BEACH
EROSION CONTROL PLAN
I'1
141
FEB 21 1994
LAND QUALITY SECTION
111J:'iHNGTO'N REGK)iNAL OFFiClr
�To, R :E:
U� FEB 2 1 199A U
EM
January 1994 ^T # gDWa6)40Z11_.
S. 0 .�
ry _
SEAL 9t;
t 8432 j
d`i e
S.Yo.•
11 Zo lq4
Prepared By:
JOSEPH S. HILL, JR. and ASSOCIATES
CONSULTING ENGINEERS and PLANNERS
1602 Harbour Drive
Wilmington, N.C. 28401
[phone]

THE KEYS OF KURE BEACH
Runoff Calculations
2. Drainage Channel Calculations
3. Outlet Protection Design
4. Sediment Basin Design
5. SECTION 1600 — Landscaping
6. SECTION 2400 — Storm Sewers

THE KEYS OF KURE BEACH
Calculations for Erosion Control Plan
Runoff Calculations
Storm Sewer Design
For calculation purposes, the site was divided into specific drainage
areas. The various project drainage structures and channels were then sized
to handle runoff generated by a 10—year, 24—hour storm, using the rational
formula (Q = CiA).
Q = Runoff. Volume
C = Runoff Coefficient (Varies according to slope, ground cover, water
surface area)
i = Intensity, inches per hour (varies according to Tc)
A = Contributory Area, Acres
Storm intensity (i)'was derived for each area by determining the time
of concentration (Tc) for the various drainage structures and applying Tc
to a storm frequency chart (attached) for the Wilmington Area.
Tc was determined by adding overland flow (see attached overland flow
nomograph) times, pipe flow velocities (see attached pipe flow graph), and
channel/swale velocities to and through the various drainage structures.
Channels and swales were designed using methods developed by H. Rooney
Malcom (see attached design discussion). The resulting project channels
were then checked for velocity using the Manning Equation:
V = 1.49 x r2/3 x S1/2
n
Keys —Er 1

THE KEYS OF KURE BEACH
Runoff Calculations
AREA #1
Tc = 10 min. (to Catch Basin)
C = 0.30
i = 5.2 in/hr.
A = 1.33 AC.
Q = 0.30 x 5.2 x 1.33 = 2.07 CFS
Provide 15" diameter RCP @ 0.2%
CFS.
AREA #2
Tc = 15 min. (to Catch Basin)
C = 0.30
i = 4.8 in/hr.
A = 1.11 AC.
Q = 0.30 x
4.8 x 1.11
= 1.60
CFS
Runoff from
Area #1
= 2.07
CFS
Total
Runoff
= 3.67
CFS
This pipe is capableof transmitting 3.0
Provide 18" diameter RCP @ 0.2%. This pipe will transmit 5 CFS.
Keys —Er 2

AREA #3
Tc = 10 min. (to Catch Bain)
C = 0.30
i = 5.2 in/hr.
A = 1.33 AC.
Q = 0.30 x 5.2 x 1.33 = 2.07 CFS
Provide 15" diameter RCP @ 0.2% as shown. This pipe will transmit 3 CFS.
AREA #4
TC = 10 Min. (to Catch Basin)
C = 0.30
i = 5.2 in/hr.
A = 1.62 AC.
Q=0.30x 5.2 x 1.66=2.59CFS
Runoff from Area #3 = 2.07 CFS
Total Runoff = 4.66 CFS
Provide 15" 0 RCP @ 0.5%. This pipe will transmit 5 CFS.
Keys —Er 3

AREA #5
Tc = 15 min. (to Catch Basin)
C = 0.30
i = 4.8 in/hr.
A = 0.87 AC.
Q = 0.3 x 4.8 x 0.87 =.1.25 CFS
Runoff from Areas #1 & 2 = 4.66 CFS
Total Runoff = 5.91 CFS
Provide 18" 0 RCP @ 0.3%. This pipe will transmit 6.5 CFS.
AREA #6
T c = 10 min. (to Catch Basin)
C = 0.30
i = 5.2 in/hr.
A = 1.05 AC.
Q = 0.30 x 5.2 x 1.05 AC = 1.64 CFS
Provide 15" 0 RCP @ 0.2%. This pipe will transmit 3 CFS
AREA #7
Tc = 10 min. (to Catch Basin)
C = 0.30
i = 5.2 in/hr.
A = 1.26 AC.
Keys —Er 4

Q = 0.30 x
5.2 x 1.26
= 1.97
CFS
Runoff from
Area #6
= 1.64
CFS
Total
Runoff
= 3.61
CFS
Provide 15" 0 RCP @ 0.3%. This pipe will transmit 4 CFS.
AREA #8
Tc = 15 min. (to Catch Basin)
C = 0.30
i = 4.8 in/hr.
A = 1.33 AC.
Q = 0.30 x 4.8 x 1.33 = 1.91 CFS
Runoff from Area #6 & 7 = 3.61 CFS
Total Runoff = 5.62 CFS
Provide 18" 0 RCP @ 0.3%. This pipe will transmit 6.5 CFS.
AREA #9
Tc = 5 min. (to inlet to sediment basin)
C = 0.30
i = 6.5 in/hr.
A = 0.39 AC.
Q = 0.30 x 6.5 x 0.39 AC = 0.76 CFS
Provide 15" 0 RCP @ 0.2%. This pipe will transmit 3 CFS.
Keys —Er 5

DRAINAGE CHANNEL CALCULATIONS
A stormwater detention pond will act as a sediment basin during
construction. Design outfall channel from stormwater pond discharge.
I. Design drainage swales.with "best" hydraulic section.. Use 100 year flow
from stormwater pond outlet pipe (33 CFS + 20 CFS for offsite
drainage). Maximum Permissible Velocity (bare soil) of 2.5 FPS. Refer
to "Design Approaches . . ." by Rooney Malcom, Page 2-2 thru 2-5 attached.
�4 W �.
M T - 0 5' - 1.0' F.B.
n = 0.03
s = 0.05 = .05/100 = .0005 ,
(EQ.
2-5)
B
= 2y
( 1 + M2 — M)
(EQ.
2-6)
K
= 2
(-M-, + 1 — M)
The depth of the best hydraulic section is defined by Manning:
(EQ. 2-7) Y = Qn(K + 2 MV ` + 1)2/3
_ 3/8
1.4947(K + M)5/3
and the bottom width is:
(EQ. 2-8)
B=Ky
the cross —sectional area of the resulting channel is:
(EQ. 2-9) A = By + My
Keys —Er 6

and the velocity of flow is:
(EQ. 2-10)
V = Q/A
Size drainage channel along west property line downstream from sediment basin
outlet:
Q=5.5CFS
M=3
.375
Y = (53)(.03)(.47.+ 2 10)'67 and K = 2(10-3)
[.49 0005 (.32 + 2) 1.67 K = 0.32
y = 4
B = Ky = 1.28' (Say 2.0')
A = 2(4) + 3(4)2
A=56
V (Manning) = 1.49 x r2/3 x S1/2 = 1.49 x 2.052/3 x .0005112 = 1.8 FPS
n .03
Conclusion: Velocity is non —erosive for bare soil and seeded grass cover.
Provide drainage ditches with bottom slope of 0.05% or less constructed to
dimensions shown on ditch section detail.
Keys —Er 7

DESIGN APPROACHES FOR
STORMWATER MANAGEMENT IN URBAN AREAS
by
H. Rooney Malcom, Jr.
Assistant Professor of Civil Engineering
and
Vernon E. Nev
Teaching and Research Assistant
North Carolina State University
Raleigh, 'North Carolina
May, 1975
9

2-2 Trapezoidal Channels
Design Objective: The objective is to select a trapezoidal channel
section.which will minimize the total cost of channel installation, consistent
with the constraints of containing the design flow at an erosion -resistant ..
velocity.
Definition Sketch:
W ��
Design Variables: Normally, flow, q, and slope, s. are invariant.
Variables under the control of the designer are the channel width, B or W,
the side slope, M, and to some extent the depth, y. The maximum permissible
velocity, Vmax, and the Manning roughness coefficient, n, are properties of
the channel lining under consideration.
Cost Sources: Channel installation costs accrue chiefly from three
sources: land taken by the channel, excavation required to provide the
specified cross-section, and the installed cost of the channel lining. The
cross-section for which the sum of these three costs is minimized is the
optimum channel section.
Hvdraulic Functions: Most channels of significant length can be
assumed to behave as if flow were uniform, in which case the Manning equation
applies. Stated to yield both velocity and flow, the equations are:
Q 1.49 AR2/3 sl/2
(2-1)
n
V . 1.49 R2/3 sI/2
n
2-2

where Q - Channel flow (cubic feet per second)
V - Cross -sectional average velocity (feet per second)
A.- Cross-sectional.area of flow (square feet)
R a Hydraulic radius (ft)
s Water surface slope (ft per ft)
n - Manning roughness coefficient (dimensionless)
The hydraulic radius, R, is found by dividing the cross -sectional area
of flow, A, by the wetted perimeter. The wetted perimeter is that part of
the channel lining in contact with water flowing in the channel.
The "Best" Hydraulic Section: It can be shown (9) that of all possible
combinations of channel depth, width and side slopes, which will just carry
the design flow, the best section is,the one which minimizes the wetted
perimeter. That section uses the least crass -sectional area, thus requiring
the least excavation, and it requires the least channel lining. If land costs
are not extremely high, this channel will almost certainly be the most
economical channel. In the event that land value is extremely high, it is
quite probable that complete enclosure of the channel in pipe is the most
economical approach.
It oan also be shown that the optimum side slope is at an angle of 60'
with the horizontal (9), or in common slope terms, 0.58 to I. Soil stability
considerations, however, usually require side slopes to be placed at 1 to 1
or flatter, except for some concrete channels.
Given that the desired side slope, M to one, has been selected for a
given channel, Streeter (9) shows that the minimum wetted perimeter, P, exists
when
P - 4y 1 + MZ - 2 My (2-3)
U
2-3

(See the Definition Sketch). From the geometry of the channel cross-section.
it is also true that
P - B + 2y 1✓ + M` (2_4)
By equating the two expressions, the relationship between.bottom width, B, and
depth, y, for the best hydraulic section is determined to exist when
B + M2 (2-5)
Further, it can be shown that maximum hydraulic efficiency (best
hydraulic section) occurs when the hydraulic radius, R, is equal to half the
depth, y.
Thus, the properties of the best trapezoidal channel are established:
that the width and depth are in a specific relationship, and that the hydraulic
radius equals the half -depth.
Making use of these properties and applying the Manning equation in the
flow fors yields two very powerful design equations, which eliminate the need
for trial -and -error solutions to determine the most economical channel. The
first defines a new quantity, k, which merely simplifies the form of the
second equation:
k . 2' ( M� ` + 1 - M) (2-6)
Then, the depth of the best hydraulic section is defined by
0/ - _n C + 2 M+ 3/
112/3 8
y (2-7)
1.49 rs fk +
The associated bottom width is simply
B -ky
. (2-8)
The cross -sectional area of the resulting channel is
A - By + My (2_9)
2-4

and the velocity of flow is
V A (2-10) .... .
Once the parameters are determined, the bottom width, B, and the channel.'.
depth, y, can be rounded to the next higher convenient values for inclusion
in construction drawings.
Velocitv Limitations: For given design conditions, the hydraulically
efficient channel may result in flow at excessive velocity. High velocity
flow enlarges the channel by attacking the banks, causing the channel to
become wider and shallower with consequent damage both alongside the channel
and downstream, where the dislodged material will choke streams and contribute
to the filling of lakes. The computed velocity for the best hydraulic section,
being subjected to design flow, should be compared to the maximum permissible
velocity for the channel lining.
The method which uses the concept of a maximum permissible cross -
sectional velocity is based on the premise that each channel lining is sensi-
tive to some average velocity of flow, above which it will be eroded, and
below which it will be stable. The premise is tenuous, because the force.
which damages the channel lining is a shear force which results from the
severe velocity gradient along the channel walls. The magnitude of the shear
force, also called the tractive force, :s a complex function of flow, channel
shape, channel alignment, the nature of the channel lining, and other factors.
(For a more detailed discussion of erosion -resistant channels, see Reference 7.)
These effects have been lumped together in a concept which treats the average
cross -sectional velocity as the most important influence on channel degrada-
tion, and experiential values have been determined for many channel linings.
Some of these are presented in Table 3. Stone -lined channels are frequently
used. Values for Manning's n and maximum permissible velocities are shown in
Chart 6.
2-3

El
m
H (ft)
N
t0
O
L
m
C
m
E
M
E
X
Cu
L (ft)
10000
1000
500
I
A
10
Note:
Use nomograph To for natural basins with well-defined channels, for overland
flow on bare earth, and for mowed -grass roadside channels.
For overland flow, grassed surfaces, multiply Tc by 2.
For overland flow, concrete or asphalt surfaces, multiply To by 0.4.
For concrete channels, multiply To by 0.2.
Figure 8.03a Time of concentration of smell drainage basins.
j
1
8.03.4

Appendices
20
15
10
8
Q 0.4
0.2
Imi
10 20 40 .60 2 3 4 6 8 12 18 24
Minutes Hours
Duration
Figure 8.03b Rainfall intensity duration curves —Wilmington.
5 10 20 40 60
Minutes
Duration
Figure 8.03c Rainfall intensity duration curves —Hatteras.
2 3 4 6 8 12 18 24
Hours
8.035

THE KEYS OF KURE BEACH
Erosion Control Plan
Outlet Protection Design
18" and 15" Diameter Pipe Outlets
Use attached Nomograph to determine rip rap size and rip rap apron
configuration for all 18" and 15" diameter RCP discharging to sediment
basin.
- Desion Criteria:
1. Flow = 6 CFS; 18" 0 outlet pipe.
2. Assume maximum tailwater conditions; well—defined channel.
Pipe Diameter = Do = 1.5'
Apron Length = La = 10' (from Nomograph)
Upstream Apron Width = Wu = 3 x Do = 3 x 1.5' = 4.5'
Downstream Apron Width = Do.+ La = 1.5' + 10' = 11.5' min.
Median Stone Size = d50 = 0.4' min. (from Nomograph)
(See attached Rip Rap Blanket Configuration — Plan View)
Select "Class B" Stone (minimum) 5" — 15"
Apron Thickness = 1.5 x dmax = 27'
Keys —Er 8

7.54 Erosion and Sediment Control Handbook
Wa Do` ..
'1 Ouoet F
pipe L. aPto� 25 to
diameter 0o ar of ca"
on`aeo9 of aFto 70
M �`m 20",
ten` fi0
Lq r /0 r 5-
40 m`mm o ry ^ I II
_m
_a_m a a yp dgti o'
rya0 om
m `m O111
a5 d m
d. t2 d c o m 9a
V P
3 5 I 10 20 50 100 200 500 1000
Discharge. fts/sec
.. � .
0.7 0.2 0.3 0.4 0.6 0.8 1 2 3 3 4 55 78 fi 7 8 10 15 20 25 '
Discharge, ma/sec
Fig. 7.45 Design of riprap outlet protection from a round pipe flowing full; minimum
tailwater conditions. (6, 14)
to find the riprap size and apron length. The apron width at the pipe end should
be 3 times the pipe diameter. Where there is a well-defined channel immediately
downstream from the apron, the width of the downstream end of the apron
should be equal to the width of the channel. Where there is no well-defined ch m-
nel immediately downstream from the apron, minimum tailwater conditions
apply and the width of the downstream end of the apron should be equal to the
pipe diameter plus the length of the apron.
EXAMPLE 7.4 Riprap Outlet Protection Design Calculation for Minimum
Tailwater Condition
Given A flow of 6 fts/sec (0.17 ms/sec) discharges from a 12-in (30-cm) pipe onto a 2
percent grassy slope with no defined channel.
Find: The required length, width, and median stone size d, for a riprap apron.
THE Na5
I $ '-� ctn d 15 "0 Ovflof-s
ds, _ O. I-

Water Conveyance and Energy Dissipation 7.57
sent. However, to simplify our calculations, we will assume that both i and A remain
constant. Therefore, the postdevelopment runoff is
0.6
0.3 (20 ft'/sec) = 40 ft'/sec 1 �.3 (0.57 ms/sec) — 1.14 mr/sec
This flow will exceed the natural capacity of the stream. It may erode the streambank
and cause flooding problems.
STEP 3. Determine how to accommodate the postdevelopment flow in a nonerosive man.
ner. There are several ways we could handle the increased flow. We could further divide
the subdivision so that approximately one-half drains into the stream and one-half
Fig. 7.47 Riprap blanket configuration for outlet protec-
tion; see the reference for design details. (2)

THE KEYS OF KURE BEACH
Erosion Control Plan
Outlet Protection Design
36" 0 Pipe Outlet
Use attached Nomographs to determine rip rap size and rip rap apron
configuration for 36" 0 pipe outlet from sediment pond. Use "worst" case
flow; 34 CFS.
Desian Criteria:
1. 36" D RCP outlet pipe with 34 CFS discharge.
2. Assume maximum tailwater conditions; well—defined channel.
Pipe Diameter = Do = 3.0
Apron Length = La = 14' (from Nomograph)
Upstream Apron Width = Wu = 3 x Do = 3 x 3.0' = 9.0'
Downstream Apron Width = Do + .4La = 3.0 + 5.6 = 8.6' min. (must extend
channel width @ 3.5' depth)
Median Stone Size = d50 = 0.20' min. (from Nomograph)
(see attached Rip Rap Blanket Configuration — Plan View)
Select "Class B" Stone (minimum) 5" — 15"
Apron Thickness = 1.5 x dmax = 27"
Each rip rap apron shall extend up channel side slopes 1' above the maximum
flow.level.
Keys —Er 9

Water Conveyance and Energy Dissipation
3 D,
OutO utlet 1 5 1 yra . D, t 0.4 L,
diameter 1 �—
DeFL,� 1
35
I10
0
`�' 30 � 100
°�
oka9 oc 90
aQ
qvr 25 0 80
\ac C
of �e°q 70
20 \�oF
_ cn
5 50
40
r 10 30 16
.ham°arya
20 a o'
Lq=� 5_
10
0 0
7.55
m;Z�m-•- 7.0
p p
0.9
n n 0.8 5
` 0.7
z a . a.6 a
3 5 10 20 50 100 200
3`f GGS 1/ Discharge, fta/sec
10.4
8. 0.3 n
�0.2
0.1 SO
.1 .2 .3 .4.5.6.7.8.9 2 3 4 56 7810 15 2025
Oischarge, m3/sec
Fig. 7.46 Design of riprap outlet protection from a round pipe flowing full; maximum
tailwater conditions. (6, 14)
Solution: Since the pipe discharges onto a flat area with no defined channel, a mini-
mum tailwater condition`✓:an he assumed.
By Fig. 7.45, the apron length La and median stone size dse are 10 ft (3 m) and 0.3 ft
(9 cm), respectively. The upstream apron width W. equals 3 times the pipe diameter Do:
W =3XD,
= 3(1 ft) = 3 ft [3(0.3 m) = 0.9 mj
The downstream apron width W4 equals the apron length plus the pipe diameter:
We=D,+L,
=ift+loft=lift (0.3m+3.0m=3.3 m)
Note: When a concentrated flow is discharged onto a slope (as in this example), gul-
lying can occur downhill from the outlet protection. The spreading of concentrated flow
THE KEYS
36 r,Q Ovfief

Water Conveyance and Energy Dissipation 7.57
ment. However, to simplify our calculations, we will assume that both i and A remain
constant. Therefore, the postdevelopment runoff is
0.6
0.3 (20 fts/sec) = 40 ft'/sec I L-3 (0.57 mt/sec) = 1.14 m'/sec I
This flow will exceed the natural capacity of the stream. It may erode the streambank
and cause flooding problems.
STEP 3. Determine how to accommodate the postdevelopment Bow in a nonerosive man-
ner. There are several ways we could handle the increased flow. We could further divide
the subdivision so that approximately one-half drains into the stream and one-half
D, = 3
3 D, = q
3I-
E
J
W (ma.. TNI =
W'(min. TW)
Fig. 7.47 Riprap blanket configuration for outlet protec-
tion; see the reference for design details. (2)

FIGURE 6
SIZES FOR RIP SAP
AND EROSION CTITROL STONE
N.C. Department of Transportation Specificaticns -
RIPRgP 8«}NKE75
1.uc Ve" 1
F
n TRni
p S
OP,1 nF
CSu'yt S�e wl,�
Cass
Class
Class
Class
1
2
A
B
Percer.
5 to
200 lbs.
25 to
250 lbs.
2" to 6"
5" to 15"I
Z0
PasSin;
(15 to
E"
90-1CO
- 30Z
shall
- 60Z
shall
300 l::s.
30- 70
weigh
a minimum
weigh
a minimum
O-
of 60
lbs. each
of 100
lbs. each
3/4"
0- 5
- No
more than
- No
more than
_10Z
tolerance
Or use
1OZ shall
5Z shall
weigh
top b
No. 4
stone,
bottom
i.e.,
1Y" to
weigh
less _
less
than 50 lbs.
sizes
3/4"
than
15 lbs. ea.
each.
- No grada-
-No grada-
tion
tion
specified
specified
Also,
r i a ss .,
2-6',
*Nctan NC -DOT Standard Specification
NORTH CAROLINA
AGGREGATES ASSOCIATION
P. O. BOX ]0607 • RALEIGH. NC 27677
PHONE Jug) 787.7055
Page 17

THE KEYS OF KURE BEACH
Sediment Basin Design Calculations
A stormwater detention pond will be used as a sediment basin to prevent off —
site transportation of sediment during construction. The sediment basin
is designed to function during a 10—year storm.
Disturbed Area
Entire site will be graded
Site Area = 15.66 AC.
Basin Dimensions
Area = 1.40 AC.
Top of Dam Elev. = 17.0'
Top of Riser = 14.9'
Riser Inv. = 14.0'
Riser Diameter = 48" 0
Conduit Pipe = 36" 0
Basin Bottom Elev. = 10.4'
Storage Volume Calculations
Provide 0.5 Ac—in. storage depth per disturbed acre
15.66 AC. x 0.5 Ac—in. = 7.8 Ac/in.
Top of Riser = 14.9'
Basin Bottom Elev. = 10.4'
Basin Storage Depth = 4.5'
7.8 Ac/in. = 54" = 0.15 Acres required basin area
Basin dimensions (Actual) = 1.40 Acres
Keys —Er 10

Runoff Calculations
Use Rational Formula to estimate runoff generated by 10 year event.
Q = CiA
Q = Runoff Volume = ?
C = Runoff Coefficient = 0.3
i = Rainfall intensity = 4.8 in/hr.
A = Area = 15.66 AC (includes allowance for off —site runoff)
Q = 0.3 x 4.8 x 15.66
Q = 22.60 CFS
Spillway
Provide 36" 0 conduit pipe at 0.4% slope from sediment basin to ditch as
shown. Provide rip rap at locations shown for energy dissipation. Provide
48 0 riser with stormwater dewatering orifice. This outlet structure will
retain the total runoff volume generated by a 10—year storm event and
gradually release this volume over a 3 to 5 day period.
Since the sediment basin will remain as a permanent stormwater management
pond, the spillway must transmit 100% of flow generated by a 100 year event.
Q = 0.3 x 7.0 x 15. 66
Q = 33.88 CFS
Conduit pipe will transmit 45 CFS.
Dam Design
Provide l' (min.) freeboard above top of riser:
Min. Pond Rim Elev. = 17.0'
Top of Riser = 14.9'
Freeboard = 2.1'
Provide 3:1 side slopes on pond banks and outfall ditch.
Keys —Er 11

SECTION 1600 - LANDSCAPING - EROSION and SEDIMENT CONTROL
A. General
The Contractor shall provide all labor, materials, equipment,
tools, and perform all work and services necessary for or incidental
to landscaping as required by these specifications and/or shown
on the plans.
All supplementary or miscellaneous items, appurtenances or
services necessary for a complete job. shall be furnished as a
part of this work, although such work shall not necessarily be
shown or specified.
All work shall comply with. the regulations of the North Carolina
Sedimentation Control Act of 1973. All erosion control devices
shall be installed and maintained as required by the North
Carolina Department of Natural Resources and Community Development.
Such measures may consist of berms, dikes, drains, and sediment basins,
or use of fiber mats, woven plastic filter cloths, gravel, mulches,
bituminous spray, and other erosion control devices or methods. All
erosion and sediment control devices shall be approved by the
Engineer prior to installation.
B. Landscaping
1. The work includes seedbed preparation. liming, fertilizing, seeding,
and mulching of all disturbed areas. The work also includes those
areas inside or outside of limits of construction that are disturbed
by the Contractor's operation.

2. The ground surface shall be clear of stumps, stones, roots,.
cables, wire, grade stakes, and other materials that might
hinder proper grading, tillage, seeding or subsequent
maintenance operations.
3. Where lawns are to be planted in areas that have not been
altered or disturbed by excavating, grading, or stripping
operations, prepare soil for lawn planting as follows:
Till to a depth of not less than 6".
Apply soil amendments and initial fertilizers as
specified.
Remove high areas and fill in depressions.
Till soil to a homogenous mixture of fine texture,
free of lumps, clods, stones, roots, and other
extraneous matter.
4. Grades on the area to be seeded shall be maintained to a true
and even condition. Maintenance shall include any necessary
repairs to previously graded areas.
5. All graded areas shall be thoroughly tilled to a depth.of at
least four 0) inches by plowing, disking, harrowing, or other
approved methods until the condition of the soil is acceptable.
On sites where soil conditions are such that high clay content
and excessive compaction cause difficulty in getting clods and
lumps effectively pulverized, the Contractor shall use the rotary
tillage machinery, until the mixing of the soil is acceptable and
no clods and clumps remain larger than 1 1/2 inches in diameter.
A firm and compact seedbed is required, and after being graded, the
seedbed shall be lightly compacted with a land roller such as a
cultipacker before and after seeding.
6. Limestone shall be dolomitic agricultural -ground limestone containing
not less than 10 percent magnesium oxide and uniformly applied at a
rate of 2000 pounds per acre prior to preparation of seedbed.

7. Fertilizer shall be the standard commercial product uniformly
applied at a rate of 1000 pounds per acre of 10-10-10 analysis.
8. The fertilizer shall be incorporated into the upper three or
four inches of prepared seedbed just prior to the last tillage
operation, but in no case shall be applied more than three days
prior to seeding. Fertilizer shall be used immediately after
delivery or stored in a manner that will not permit.it to harden
or destroy its effectiveness. When hydroseeding equipment is:
used for seeding, fertilizer shall be applied simultaneouly
with seed, using the above rates of application.
9. Seed shall be certified seed or equivalent based on North Carolina
Seed Improvement Association requirements for certification. All
seed shall be furnished in sealed standard containers. Seed
which has become wet, moldy, or otherwise damaged prior to seeding,
will not be acceptable.
10. Seeding shall be accomplished with. power -drawn planters and land
packer or hydroseeding equipment at the rate of:
From September 15 to April 15; 75 pounds per acre of Tall
Fescue, Kentucky 31 or Alta Tall Fescue.
100 pounds per acre Unhulled Bermuda.
From April 15 to September.15:
75 pounds per acre of Hulled Bermuda.
75 pounds per acre of Tall Fescue, Kentucky 31, or Tall
Fescue.
1% maximum weed seed content permitted.
11. When conditions are such, by reason of drought, high,wi,nds, excessive
moisture or other. factors where satisfactory results will not be
obtained, the work shall be stopped and resumed only when conditions
are favorable.

12. Apply 4,000 - 5,000 lb/acre grain straw or equivalent cover of
another suitable mulching material. Anchor mulch by tacking
with asphalt, roving, or netting. Netting is the preferred
anchoring method on steep slopes.
13. Method used to apply the mulch shall be mechanical type equipment
and shall obtain a uniform distribution. to permit sunlight to
penetrate to the ground surface.
14. Provide and maintain temporary piping, hoses, and lawn watering
equipment as required to convey water from water sources and to
keep.lawn areas uniformly moist as required for proper growth.
Maintain lawns by watering, fertilizing, weeding, mowing,
trimming, and other operations such as rolling, regrading, replanting
as required to establish a smooth, acceptable lawn, free of eroded
or bare areas.
Remulch with new mulch in areas where mulch has been disturbed
by wind or maintenance operation sufficiently to nullify its
purpose. Anchor as required to prevent displacement. Replace
bare areas using same materials specified for laNms.

SECTION 2400 - STORM SEWER
A. General i.
1. Description - This item shall consist of all reinforced concrete
plus other storm pipe of the sizes and dimensions called for on
the plans, furnished and installed at such places as are designated
on the plans or by the Engineer with the lines and grades given
and in conformity with these specifications.
2. This item 'shall also include the furnishing and construction of such
joints and connections to other pipes, boxes, storm manholes,
junction manholes, catch basins, etc., as may be required to complete
the work as shown on the plans. All snoplLmnentary or miscellaneous
items, appurtenances and devices incidental to or necessary for a
sound, secure and complete storm drainage system, shall be furnished
and installed as part of this work, although all such work may not
be specifically shown or identified. The Contractor shall check all
drawings relative to dimensions, elevations, sizes, and locations of
all work. Any discrepancies shall be adjusted prior to proceeding
with the work.
3. Materials- All materials shall be free from any defects and in general
be in accordance with the plans and all applicable ASTM or other
standards.
4. All reinforced concrete storm pipe used in this project shall be
manufactured in accordance with and shall meet the test requirements
and conditions set forth in specifications for reinforced concrete

sewer pipe, of the ASTM, serial designated C 76 (latest
revision), and C 507 (latest revision). Class III pipe shall
be used except where Class IV pipe is specifically called for
on the plans. Gaskets shall be RAM-NEK as manufactured by K.T.
Synder Company, Inc. of Houston, Texas, and meet or exceed all
requirements of ASTM C-443 and Federal Specifications SS-50002I0,
or equal as provided by Engineer.
5. Ali vitrified clay used in this project shall comply with ASTM
Designation C-700 (latest revision). A11 clay sewer pipe shall
be extra strength pipe and each length of pipe shall bear the
initials or name of the manufacturer, the location of the plant
and the words, "Extra Strength" or the symbol "ES". Joints for
Vitrified Clay SelT and Spigot Pipe shall comoTy with ASTM
Designation C 425 (latest revision). The spigot may be formed from
an isophthalic polyester casting bonded to the clay pipe and
designed to receive a high quality " "
0 ring gasket.
6. All ductile iron pipe and fittings used in this project shall be
bituminous cpated and shall be in accordance with the latest re-
visions of the following: "American Standards Association" Standards
ASA-A 21.4; ASA-A 21.10, ASA-A 21.11; ASA-A 21.50 (Class 51); and
ASA-A 2T.51 (Class 51). All fittings-shaTT be Class T50 in accordance
with ASA-A 27.10, latest revision.
7. Concrete poured in place shall be 4000 psi (28 day strength) unless
otherwise specified. Precast concrete shall be in accordance with
the applicable ASTM.
8. Reinforcing Steel - Reinforcing steel shall comply with ASTM A675,
Grade 60 unless otherwise shown or specified.
TM

9. Casting - Castings for catch basins, manhole covers, downspout
boots and the like shall be of tough, even grained ductile iron,
free from warp, projections, sand holes, burnt -on sand, and
other injurious defects, and of the type and dimensions shown by
the draw.ings. Ail such iron frames and covers shall be machined
sufficiently to prevent rocking. Before leaving the foundry castings
shall be thoroughly cleaned, subjected to hammer test for soundness,
and given two coats of coal tar pitch varnish.
10. Cleanout - Cleanouts are required as designated on plans.
B, hatch Basins and Oroo inlets
1. Materials shall conform to the requirements of the N.C. Department
of Transportation Saecifications.
2. Brick - Brick used in catch basins and/or drop inlets shall be
in conformity to NCDOT Standard Specifications for Roads. and
Structures 1978 and shall be laid with full shove joints; ail joints
shall be thoroughly filled with mortar and the thickness of joints
on the inside of the wall must not be more than three -eights (3/8)
of an inch.
3. Concrete Block- Solid concrete block shall be made by a manufacturer
approved by the Engineer and shall be tested and certified. by a
reputable Testing Laboratory approved by the Engineer.
4. Concrete - Shall be 4000 psi (28 day strength) unless otherwise
specified. Precast concrete shall be as required by the applicable
ASTM.

n
5. Manholes - Manholes shall be in accordance with the plans and
general specifications under Section 0300-"Planholes". Precast
manholes shall be in accordance with the applicable ASTM.
6. Castings - Shall be in accordance with specifications in other
sections and as shown on plans.
7. Contractor shall examine the substrate and the conditions under
which concrete formwork is to be performed. Do not proceed with
the work until unsatisfactory conditions have been corrected.
8. Unless otherwise shown or specified, design, construct, erect,
maintain and remove forms and related structures for cast -in -
place concrete work in compliance with the American Concrete
Institute Standard ACT 347, "Recommended Practice for Concrete
Formwork".
9. Allowable Tolerances - Construct formwork to provide completed
concrete surfaces complying with the tolerances specified in
ACI 347 after removal of forms and prior to -patching and finishing
of cast -in -place formed surfaces.
10. Design of Formwork
(a) Design and construction of formwork is responsibility of
Contractor.'
(b) Design, erect, support, brace, and maintain formwork and
shoring to safely support all superimposed concrete and con-
struction loads placed on them. Transmit loads to ground by
formwork system and in -place construction that has attained
d

adequate strength for that purpose. Construct formwork
to provide concrete members and structures of correct
sizes, shape, alignment, elevation and position.
(c) Design formwork to be readily removable without impact,
shock, or damage to cast -in -place concrete surfaces and
adjacent materials.
II. Form Construction - General
(a) Construct forms to comply with ACI 347, to the exact sizes,
shapes, lines and dimensions shown, and as required to
obtain accurate alignment, location, grades, level, and
plumb work in finished structures. Provide for openings,
Offsets, sinkages, keyways, recesses, moldings, rustications,
reglets, chamfers, blocking, screeds, bulkheads, anchorages,
and inserts, and other features required.
12. Accessories and Embedded Items
(a) Installation of Embedded Items --Set and build into the work
anchorage devices and other embedded items required for work
of other trades that is at -',,ached to, or supported by, concrete.
Use setting drawings, diagrams, instructions and directions
provided by suppliers of items to be attached thereto. Care-
fully coordinate and accurately locate embedded items.
73. Concrete Reinforcement - Fabrication
(a) Detail and fabricate reinforcing bars in compliance with.
ACI Manual of Standard Practice for Detailing Reinforced

Concrete Structures (ACI-315) and Chaoter 7 "Details of
Reinforcement" ACI Building Code (ACI 318). In event of
fabricating errors, do not rebend or straighten bars in
any manner that will injure or weaken material. Cold bend
all bars.
(b). Do not use any reinforcing having any of following
defects:
1. Bar lengths, depths and bends exceeding specified
fabrication tolerances.
2. Bends not indicated on project drawings or approved
shop drawings.
3. Cracks or splits occurring at bends.
4. Bars with reduced cross-section due to excessive
rusting or other causes.
14. Placing Reinforcing - Comply with CRSI "Placing Reinforcing Bars",
and with ACI Building Code (ACI 318), Chapter 7 "Details of
Reinforcement".
15. Do not place concrete an reinforcing which has ruse, mill scale,
form oil, earth, ice, and other materials which will reduce or
destroy bond.
16. Accurately position, support, tie and secure reinforcement against
displacement by construction operations drawings. Where not shown,
provide concrete cover as specified in paragraph 7.14 of ACI 318.
17. Space and locate reinforcing. bars as shown, on drawings and within
placement tolerances stated in CRSI "Placing Reinforcing Bars".
,-

0
Maintain minimum clear distances between bars as stated in
paragraph 7.4 of ACI 318. When reinforcing cannot be placed
in its indicated locations within specified placing tolerances,
or with specified minimum clear distances between rebars, notify
Engineer immediately. Do not pour concrete until corrective
action has been determined by Engineer.
18. Provide lap splice lengths as indicated an drawings. Where not
indicated, provide top bar class C tension lap splice lengths as
specified in paragraph 7.6 of ACI 318. Place lap spliced ends
of bars in contact with each other and tightly wire together.
19. Refer to other applicable sections of the contract documents re-
garding concrete, etc.
0
0