HomeMy WebLinkAboutSW8990847_HISTORICAL FILE_20000225STORMWATER DIVISION CODING SHEET
POST -CONSTRUCTION PERMITS
PERMIT NO.
SW8 1� 110 <� q-1
DOC TYPE
❑ CURRENT PERMIT
❑ APPROVED PLANS
HISTORICAL FILE
❑ COMPLIANCE EVALUATION INSPECTION
DOC DATE
2006 02215
YYYYMMDD
State of North Carolina
Department of Environment
and Natural Resources
Wilmington Regional Office
James B. Hunt, Jr., Governor
Bill Holman, Secretary
Division of Water Quality
Mr G S Chhabra, Manager
JSS Wilmington, LLC
104 Brittany Place
Cary, NC 27511
Dear Mr Chhabra
L74
NCDENR
NORTH CAROLINA DEPARTMENT OF
ENVIRONMENT AND NATURAL RESOURCES
February 25, 2000
Subject Permit No SW8 990847
Country Inn Suites Hotel
High Density Stormwater Project
New Hanover County
The Wilmington Regional Office received a complete Stormwater Management Permit Application for Country Inn
Suites Hotel on February 16, 2000 Staff review of the plans and specifications has determined that the project, as
proposed, will comply with the Stormwater Regulations set forth in Title 15A NCAC 2H 1000 We are forwarding
Permit No SW8 990847 dated February 25, 2000, for the construction of Country Inn Suites Hotel
This permit shall be effective from the date of issuance until February 25, 2010, and shall be subject to the
conditions and limitations as specified therein Please pay special attention to the Operation and Maintenance
requirements in this permit Failure to establish an adequate system for operation and maintenance of the stormwater
management system will result in future compliance problems
If any parts, requirements, or limitations contained in this permit are unacceptable, you have the right to request an
adjudicatory hearing upon written request within thirty (30) days following receipt of this permit This request must
be in the form of a written petition, conforming to Chapter 150B of the North Carolina General Statutes, and filed
with the Office of Administrative Hearings, P O Drawer 27447, Raleigh, NC 27611-7447 Unless such demands
are made this permit shall be final and binding
If you have any questions, or need additional information concerning this matter, please contact Linda Lewis, or
me at (910) 395-3900
Sincerely,
CZL- c_, ,
Rick Sluver
Water Quality Regional Supervisor
RSS/arl S \WQS\STORMWAT\PERMIT\990847 FEB
cc Steven Rice, P E
Tony Roberts, New Hanover County Inspections
Beth Easley, New Hanover County Engineering
Linda Lewis
Wilmington Regional Office
Central Files
127 Cardinal Dr Ext, Wilmington, North Carolina 28405 Telephone 910-395-3900 FAX 910-350-2004
An Equal Opportunity Affirmative Action Employer 50% recycled/10% post -consumer paper
State Stormwater Management Systems
Permit No SW8990847
STATE OF NORTH CAROLINA
DEPARTMENT OF ENVIRONMENT AND NATURAL RESOURCES
DIVISION OF WATER QUALITY
STATE STORMWATER MANAGEMENT PERMIT
HIGH DENSITY DEVELOPMENT
In accordance with the provisions of Article 21 of Chapter 143, General Statutes of North Carolina as amended, and
other applicable Laws, Rules, and Regulations
PERMISSION IS HEREBY GRANTED TO
JSS Wilmington, LLC
Country Inn Suites Hotel
New Hanover County
FOR THE
construction, operation and maintenance of a wet detention pond in compliance with the provisions of 15A NCAC
2H 1000 (hereafter referred to as the "stormwater rules') and the approved stormwater management plans and
specifications and other supporting data as attached and on file with and approved by the Division of Water Quality
and considered a part of this permit
This permit shall be effective from the date of issuance until February 25, 2010 and shall be subject to the following
specified conditions and limitations
I. DESIGN STANDARDS
1 This permit is effective only with respect to the nature and volume of stormwater described in the
application and other supporting data
2 This stormwater system has been approved for the management of stormwater runoff as described on page 3
of this permit, the Project Data Sheet The stormwater control has been designed to handle the runoff from a
maximum of 95,752 square feet of impervious area
3 Approved plans and specifications for this project are incorporated by reference and are enforceable parts of
the permit
4 The tract will be limited to the amount of built -upon area indicated on page 3 of this permit, and per
approved plans Lot 1 is limited to a maximum of 28,663 ft2 of built -upon area Lot 2 is limited to a
maximum of 69,309 ft2
2
State Stormwater Management Systems
Permit No SW8990847
Project Name
Permit Number
Location
Applicant
Mailing Address
Application Date
Name of Receiving Stream/Index #
Classification of Water Body
If Class SA, chloride sampling result
Pond Depth, feet
Permanent Pool Elevation, FMSL
Drainage Area, acres
Total Impervious Surfaces, ft2
Offsite Area entering Pond, ft2
Required Surface Area, ft2
Provided Surface Area, ft2
Required Storage Volume, ft3
Provided Storage Volume, ft'
Temporary Storage Elevation, FMSL
Controlling Orifice
DIVISION OF WATER QUALITY
PROJECT DESIGN DATA SHEET
Country Inn Suites Hotel
SW8 990847
New Hanover County
Mr G S Chhabra, Manager
JSS Wilmington, LLC
104 Brittany Place
Cary, NC 27511
February 16, 2000
Spring Branch / (CFR 18-74-63-1)
"C Sw"
s n/a
6
36
3 15
95,752
Lot 1 @70% BUA (28,663 ft2)
5,336
5,692
7,753
13,323
.3795
1 " � pipe
3
State Stormwater Management Systems
Permit No SW8990847
II. SCHEDULE OF COMPLIANCE
The stormwater management system shall be constructed in it's entirety, vegetated and operational for its
intended use prior to the construction of any built -upon surface
During construction, erosion shall be kept to a minimum and any eroded areas ofthe system will be repaired
immediately
The permittee shall at all times provide the operation and maintenance necessary to assure the permitted
stormwater system functions at optimum efficiency The approved Operation and Maintenance Plan must
be followed in its entirety and maintenance must occur at the scheduled intervals including, but not limited
to
a Semiannual scheduled inspections (every 6 months)
b Sediment removal
c Mowing and revegetation of side slopes
d Immediate repair of eroded areas
e Maintenance of side slopes in accordance with approved plans and specifications
f Debris removal and unclogging of outlet structure, orifice device and catch basins and piping
g Access to the outlet structure must be available at all times
4 Records of maintenance activities must be kept and made available upon request to authorized personnel
ofDWQ The records will indicate the date, activity, name of person performing the work and what actions
were taken
5 Decorative spray fountains will not be allowed in the stormwater treatment system
6 The facilities shall be constructed as shown on the approved plans This permit shall become voidable unless
the facilities are constructed in accordance with the conditions of this permit, the approved plans and
specifications, and other supporting data
7 Upon completion of construction, prior to issuance of a Certificate of Occupancy, and prior to operation of
this permitted facility, a certification must be received from an appropriate designer for the system installed
certifying that the permitted facility has been installed in accordance with this permit, the approved plans
and specifications, and other supporting documentation Any deviations from the approved plans and
specifications must be noted on the Certification
8 If the stormwater system was used as an Erosion Control device, it must be restored to design condition prior
to operation as a stormwater treatment device, and prior to occupancy of the facility
The following items will require a modification to the permit
a Any revision to the approved plans, regardless of size
b Project name change
c Transfer of ownership
d Redesign or addition to the approved amount of built -upon area
e Further subdivision, acquisition, or sale of the project area The project area is defined as all property
owned by the permittee, for which Sedimentation and Erosion Control Plan approval was sought
f Filling in, altering, or piping of any vegetative conveyance shown on the approved plan
10 The Director may determine that other revisions to the project should require a modification to the permit
11 The permittee shall notify DWQ of any mailing address changes within 30 days of moving
1l
State Stormwater Management Systems
Permit No SW8990847
12 A copy of the approved plans and specifications shall be maintained on file by the Permittee for a minimum
of ten years from the date of the completion of construction
13 Prior to the sale of any portion of the property, an access/maintenance easement to the stormwater facilities
shall be granted in favor of the permittee if access to the stormwater facilities will be restricted by the sale
of any portion of the property
14 The permittee is responsible for verifying that the proposed built -upon area does not exceed the allowable
built -upon area
15 The runoff from all built -upon area on the project must be directed into the permitted stormwater control
system
16 The Director may notify the permittee when the permitted site does not meet one or more of the minimum
requirements of the permit Within the time frame specified in the notice, the permittee shall submit a written
time schedule to the Director for modifying the site to meet minimum requirements The permittee shall
provide copies of revised plans and certification in writing to the Director that the changes have been made
III. GENERAL CONDITIONS
This permit is not transferable In the event there is a desire for the facilities to change ownership, or there
is a name change of the Permittee, a formal permit request must be submitted to the Division of Water
Quality accompanied by an application fee, documentation from the parties involved, and other supporting
materials as may be appropriate The approval of this request will be considered on its merits and may or
may not be approved
2 Failure to abide by the conditions and limitations contained in this permit may subject the Permittee to
enforcement action by the Division of Water Quality, in accordance with North Carolina General Statute
143-215 6A to 143-215 6C
The issuance of this permit does not preclude the Permittee from complying with any and all statutes, rules,
regulations, or ordinances which may be imposed by other government agencies (local, state, and federal)
which have jurisdiction
In the event that the facilities fail to perform satisfactorily, including the creation of nuisance conditions,
the Permittee shall take immediate corrective action, including those as may be required by this Division,
such as the construction of additional or replacement stormwater management systems
The permittee grants DENR Staff permission to enter the property for the purpose of inspecting all
components of the permitted stormwater management facility
The permit may be modified, revoked and reissued or terminated for cause The filing of a request for a
permit modification, revocation and reissuance or termination does not stay any permit condition
Permit issued this the 25th day of February, 2000
NORTH CAROLINA ENVIRONMENTAL MANAGEMENT COMMISSION
— �--i
y, Kerr T Stevens, Director
l " ' Division of Water Quality
By Authority of the Environmental Management Commission
Permit Number SW8 990847
State Stormwater Management Systems
Permit No SW8990847
Country Inn Suites Hotel
Stormwater Permit No SW8 990847
New Hanover County
Designer's Certification
1, , as a duly registered in
the State of North Carolina, having been authorized to observe (penodically/weekly/full time) the construction of
the project,
for (Project Owner) hereby state that, to the best of my abilities, due care
and diligence was used in the observation of the project construction such that the construction was observed to be
built within substantial compliance and intent of the approved plans and specifications
The checklist of items on page 2 of this form is included in the Certification
Noted deviations from approved plans and specification
Signature
Registration Number
Date
SEAL
0
State Stormwater Management Systems
Permit No SW8990847
Certification Requirements
1 The drainage area to the system contains approximately the permitted acreage
2 The drainage area to the system contains no more than the permitted amount of built -upon area
3 All the built -upon area associated with the project is graded such that the runoff drains to the system
4 The outlet/bypass structure elevations are per the approved plan
5 The outlet structure is located per the approved plans
6 Trash rack is provided on the outlet bypass structure
All slopes are grassed with permanent vegetation
Vegetated slopes are no steeper than 3 1
The inlets are located per the approved plans and do not cause short-circuiting of the system
10 The permitted amounts of surface area and/or volume have been provided
11 Required drawdown devices are correctly sized per the approved plans
12 All required design depths are provided
13 All required parts of the system are provided, such as a vegetated shelf, and a forebay
14 The overall dimensions of the system, as shown on the approved plans, are provided
cc NCDENR-DWQ Regional Office
Tony Roberts, New Hanover County Building Inspector
Date Receivedµ
Fee Paid
Permit Number
1S __ —
,y
`T -� lD
State of North Carolina
Department of Environment and Natural Resources
Division of Water Quality
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
Thu form may be photocopied for use as an onginal
I. GENERAL INFORMATION
1 Applicants name (specify the name of the corporation, individual, etc who owns the project)
TSS VJ%t- A1Ail.TnA1 LLC.
2 Print Owner/Signing Official's name and title (person legally responsible for facility and compliance)
G S CyjµAil RA H2Y/�C1 Zr�
3 Mailing Address for person listed in item 2 above
109' BRITTRNY Pt-AC-E
City G A R Y State /.l.0 zip z7 511
Telephone Number L 9 I °1 ) 8 54 — 92 3 8
4 Project Name (subdivision, facility, or establishment name -should be consistent with project name on
plans, specifications, letters, operation and maintenance agreements, etc)
GDUAiTRY .>=nrtil SUITE 146TE(_
5 Location of Project (street address)
2-56 E 4STw00D _i�oAD
City VJ l i-M I N G TO IJ County N E W ANo v 5 R
6 Directions to project (from nearest major intersection)
LoT 6 3 15 ALz6 T2AoT bN Tir'E ERST SIDE of SMITH (RE.=k Atc✓y
AT T+tE 1ArrE25Er-T-10A,1 OF EAST( oa RoAD Amb SMITH 4AEEk PAR)G, Ay
7 Latitude 3 4° 14 36 i1 Longitude -770 -51 160
i1 of project
8 Contact person who can answer questions about the project
Name ST Ey EN M. 1Z I G Telephone Number- ( 919 ) 4 ie z - 0 4 7 +
II. PERMIT INFORMATION-
1 Specify whether project is (check one)
Form SWU-101 Version 3 99
New
Page 1 of 4
Renewal Modification
If this application is being submitted as the result of a renewal or modification to an existing pernut, list the
existing peraut number and its issue date (if known)
'w
3 Specify the type of project (check one)
_Low Density __Y__I-hgh Density _Redevelop _General Permit _Other
4 Additional Project Requirements (check applicable blanks)
_CAMA Major _Sedunentation/Erosion Control _404/401 Permit _NPDES Stormwater
Information on required state permits can be obtained by contacting the Customer Service Center at
1-877-623-6748
III PROJECT INFORMATION
1 In the space provided below, summarize how stormwater will be treated Also attach a detailed narrative
(one to two pages) describing stormwater management for the project
SToRMyiATE2 W164- 86 DiRELTED To RAID TRERrEo iN A wET PErEnlrioA/
SASiN AT TN6 R6AR of T-ME S/TE T-NE TREArEb RUNOFF WILL- E15
Li ISLiiARGE� Tb A DESI&AIFO LjiHNNEG. IsEE A77'R4-tE0 PL14n/5)
2 Stormwater runoff from this project drams to the _
3 Total Project Area 2. , Z I acres (L.4 2)
5 How many drainage areas does the project have? I
River basin
4 Project Built Upon Area 7 1 , 4 %
6 Complete the following information for each drainage area If there are more than two drainage areas in the
project, attach an additional sheet with the information for each area provided in the same format as below
Basui Infoiriiatron
a
$ auiag �_=
Th erArea 1
�m .m .v. m .ecw�.'r W
r ,D;airiage,Area2 =
exti.
Receiving Stream Name
3a R 0 L F f GR E E AC
Receiving Stream Class
eL
Drainage Area
3.6 Acz s
Existing Impervious* Area
�-+z
Proposed Im ervious Area
-Fr-Z q5 i5`L
%Impervious* Area (total)
(017,970
,9" V`iche St&facetAiea
Drairiage Aiea1 ` "
c n DrainagrAie a2 ;
On -site Buildings
On -site Streets
I +z
On -site Parking
2
3 2 11
On -site Sidewalks
<j p(o }Z
Other on -site
U I(, W
efhrte
+
'Z 3
Total 4.4 - +T q5 ?rj2
I Total
Impervious area is defined as the built upon area including, but not limited to, buildings, roads, parking areas,
sidewalks, gravel areas, etc
Form SWU-101 Version 3 99
Page 2 of 4
How was the off -site impervious area listed above derived? USE 0 COUN r `( TO PO 4 T-AX
MF4Ps 6FFstr£ SURVEYS AND sn-F SuRVEYs
IV DEED RESTRICTIONS AND PROTECTIVE COVENANTS
The following italicized deed restrictions and protective covenants are required to be recorded for all
subdivisions, outparcels and future development prior to the sale of any lot If lot sizes vary significantly, a
table listing each lot number, size and the allowable built -upon area for each lot must be provided as an
attachment
1 The following coT�enants ar t tt ded to ensure ongoing compliance with state stormwater management permit
number `J�.L70 '7qC as issued by the Division of Water Quality These covenants may
not be changed or deleted without the consent of the State
28CoCar Lc7f 1 mac+ Cal, 30q FFZ fu L�f Z
2 No more than squaw -feet of any let shall be covered by structures or impervious materials
Impervious materals include asphalt, gravel, concrete, back, stone, slate or similar material but do not include wood
decking or the water surface of swimming pools
3 Swales shall not be filled in, piped, or altered except as necessary to provide driveway crossings
4 Built -upon area in excess bf the permitted amount requires a state stormwater management permit modification prior to
construction
5 All permitted runoff from outparcels or future development shall be directed into the permitted stormwater control
system These connections to the stormwater control system shall be performed in a manner that maintains the
integrity and performance of the system as permitted
By your signature below, you certify that the recorded deed restrictions and protective covenants for this project
shall include all the applicable items required above, that the covenants will be binding on all parties and
persons claiming under them, that they will run with the land, that the required covenants cannot be changed or
deleted without concurrence from the State, and that they will be recorded prior to the sale of any lot
V SUPPLEMENT FORMS
i
The applicable state stormwater management permit supplement form(s) listed below must be submitted for
each BMP specified for this project Contact the Stormwater and General Pernuts Umt at (919) 733-5083 for the
status and availability of these forms
Form SWU-102
Wet Detention Basin Supplement
Form SWU-103
Infiltration Basm Supplement
Form SWU-104
Low Density Supplement
Form SWU-105
Curb Outlet System Supplement
Form SWU-106
Off -Site System Supplement
Form 5WU-107
Underground Infiltration Trench Supplement
Form SWU-108
Neuse River Basin Supplement
Form SWU-109
Innovative Best Management Practice Supplement
Form SWU-101 Version 3 99 Page 3 of 4
VI. - SUBMITTAL REQUIREMENTS
Only complete application packages will be accepted and reviewed by the Division of Water Quality (DWQ).
A complete package includes all of the items listed below The complete application package should be
submitted to the appropriate DWQ Regional Office
1 Please indicate that you have provided the following required information by imt3ahng in the space
provided next to each item
Initials
• Original and one copy of the Stormwater Management Permit Application Form 7' G
• One copy of the applicable Supplement Form(s) for each BMP T. G
• Pernut apphcation,processing fee of $420 (payable to NCDENR) , C
• Detailed narrative description of stormwater treatment/management
• Two copies of plans and specifications, including
- Development/Project name
- Engineer and firm
-Legend;
- North airow
- Scale
- Revision number 8_ date
- Mean high water line
- Dimensioned property/project boundary
- Location map with named streets or NCSR numbers
- Original contours, proposed contours, spot elevations, finished floor elevations
- Details of roads, drainage features, collection systems, and stormwater control measures
- Wetlands delineated, or a note on plans that none exist
- Existing drainage (including off -site), drainage easements, pipe sizes, runoff calculations
- Drainage areas delineated
- Vegetated buffers (where required)
VII. AGENT AUTHORIZATION
If you wish to designate authority to another individual or fum so that they may provide information on your
behalf, please complete this section \
Designated agent (individual or firm) R i t-E + A55 o e-i ATE S &F-D 6R EDLE A6 AGENT\
Mailing Address II (L NEW ED iTioN Cl*
City GHRY
Phone ( q 19 ) 9 (o Z — 64 7 4
VIII. APPLICANT'S CERTIFICATION
State A) G • Zip S-7 61I
Fax ( 919 ) 1-&7 -S707
I, (print or type name of person listed in General Information, item 2) G , 'S. C H A A S iZA
certify that the information included on this permit application form is, to the best of my knowledge, correct and
that the project will be constructed in conformance with the approved plans, that the required deed restrictions
and protective covenants will be recorded, and that the proposed project complies with the requirements of 15A
NCAC 2H 1000
Signature_
Form SWU-101 Version 3 99 Page 4 of 4
Date — z- O —C
111 LETTER
RICE &
ASSOCIATES
TO Ms Linda Lewis
NCDENR
127 Cardinal Drive Extension
Wilmington, INC 28405
OF TRANSMITTAL
DATE FEBRUARY 15. 2000
RE SW8990847
Country Inn Suites
PIN 99 055
SENDING ® Attached ❑ Under Separate Cover ❑ Via US Mail ® Overnight UPS/FedEx ❑ Messenger ❑ To Be Picked Up By Recipient
` 2 copies of sheet D-1 with revised labeling of drawdown
2 copies of sheet D-3 with revised labeling of drawdown & storage elevation
Y JHII/1 VAIA I b N
E C E I V E
t��
COMMENTS D E M
PROJ N
AS REQUESTED
COPY TO Mr Gary Chhabra, JSS Wilmington, LLC
I
SENT BY X.j�
Ted Credle
1
116 New Edition Court • Cary, North Carolina 27511 • Voice 919 462 8474 • Fax 919 462 8707 • Email nceassociates@telex com
State of North Carolina
Department of Environment
and Natural Resources
Wilmington Regional Office
James B Hunt, Jr, Governor
Bill Holman, Secretary
Division of Water Quality
February 14, 2000
Mr G S Chhabra, Manager
JSS Wilmington, LLC
104 Brittany Place
Cary, NC 27511
NCDENR
NORTH CAROLINA DEPARTMENT OF
ENVIRONMENT AND N. RA RESOURCES
Subject ACKNOWLEDGMENT OF RECEIPT AND
REQUEST FOR ADDITIONAL INFORMATION
Stormwater Project No SW8 990847
Country Inn Suites Hotel
New Hanover County
Dear Mr Chhabra
The Wilmington Regional Office received previously requested information for the Stormwater
Management Permit Application for Country Inn Suites Hotel on January 31, 2000 A preliminary review of
that information has determined that the application is not complete The following information is needed to
continue the stormwater review
Sheet D-1, the proposed basin details, shows the corrected temporary storage elevation, but still
shows the'drawdown onfice as 6" The other basin detail, on sheet D-3, still shows the
temporary storage elevation as 36 8, but shows a drawdown onfice size of 2" The calculations
indicate that 1" will be used Please revise the onfice size to 1" on both details, and correct the
temporary pool elevation on sheet D-3 to 37 95 it is probably best to have just one basin detail,
to avoid confusion about which one is right Please submit 2 copies of the revised sheets
127 Cardinal Dr Ext, Wilmington, North Carolina 28405 Telephone 910-395-3900 FAX 910-350-2004
An Equal Opportunity Affirmative Action Employer 50% recycled/10 % post -consumer paper
Mr Chhabra
February 14, 2000
Stormwater Project No SW8 990847
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 March 14, 2000, or the application will be
returned as incomplete The return of a project will necessitate resubmittal of all required items, including the
application fee
If you need additional time to submit the information, please mail or fax your request for a time
extension to the Division at the address and fax number at the bottom of this letter The request must indicate
the date by which you expect to submit the required information. The Division is allowed 90 days from
the receipt of a completed application to issue the permit
The construction of any impervious surfaces, other than a construction entrance under an approved
Sedimentation Erosion Control Plan, is a violation of NCGS 143-215 1 and is subject to enforcement action
pursuant to NCGS 143-215 6A
Please reference the State assigned project number on all correspondence Any original documents that
need to be revised have been sent to the engineer or agent All original documents must be returned or new
originals must be provided Copies are not acceptable If you have any questions concerning this matter please
feel free to call me at (910) 395-3900
Sincerely,
Linda Lewis
Environmental Engineer
RSS/arl S \WQS\STORMWAT)ADDINFO\990847 FEB
cc Linda Lewis
Ted Credle
127 Cardinal Dr Ext , Wilmington, North Carolina 28405 Telephone 910-395-3900 FAX 910-350-2004
An Equal Opportunity Affirmative Action Employer 50% recycled/10% post -consumer paper
i
P 1
* * * (COMMUNICATION RESULT REPORT ( FEB 14 2000
FILE MODE OPTION ADDRESS (GROUP)
-------------------------- 7-------------------------------
285 MEMORY TX 8-9194628707
1 27PM ) *
TTI
RESULT
-----------
OK
*
NCDENR WIRO
PAGE
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P 3/3
---------- -------------------------------------------------------
REASON FOR ERROR
E-1) HANG UP OR LINE FAIL E-2) BUSY
E-3) NO ANSWER E-4) NO FACSIMILE CONNECTION
State of North Carolina
Department of Environment and Natural Resources
Wilaungton Regional Office
James B Hunt, Governor Bill Holman, Secretary
FAX COVER SHEET
Date: 2 1 Q— 2 OOO No. of Pages: 3
To: TeD C12ED`E From: Linda Lewis
Company: RICO S ,Assoc /,4.r-S5 Water Quality Section - Stormwater
FAX #:_ GI.4 - 4(o2 — $7o-* FAX #: 910�350-2004
DWQ Stormwater Project # SLu8
REMARKS; I
127 Cardinal Drive Extension, WilmmstM NC 2S405-3545 Telephone (910) 395-3900 FAX (910) 350-2004
An Equal Opportomty Affirmative Acton Employer
I i LETTER OF
RICE &
ASSOCIATES
TO Ms Linda Lewis
NCDENR
Wilmington Regional Office
Water Quality Section
127 Cardinal Drive Extension
Wilmington, NC 28405
1
T
FAJANttt W T —
DATE. JANUARY 27, 2000
RE SW8990847
Country Inn Suites, Wilmington
PN• 99 055
SENDING 0 Attached ❑ Under Separate Cover 0 Via US Mail 0 Overnight UPSIFedEx ❑ Messenger ❑ To Be Picked Up By Recipient
I
" 3 sets of revised plans showing changes made to the proposed channel the outlet weir & drawdown
" Set of Calculations explaining how the proposed channel and proposed basin were designed
COMMENTS.
FOR YOUR REVIEW AND APPROVAL
COPY TO Mr Gary Chhabra, JSS Wilmington, LLC
SENT BY. z—,JA ef g
Ted Credle
116 New Edition Court . Cary, North Carolina 27511 . Voice 919 462 8474 9 Fax 919 462 8707 • Email nceassociates@telD(com
COUNTRY INN SUITES HOTEL
NEW HANOVER COUNTY, NORTH CAROLINA
255 Eastwood Road
Wilmington, North Carolina
2 21 Acres
HYDROLOGY $ HYDRAULIC CALCULATIONS
15S WILMINGTON, LAC
104 BRITTANY PLACE
CARY, NORTH CAROLINA 2751 1
919 — 481 - 1200
prepared by
' I
&.
RICE &
ASSOCIATES
116 New Edition Court
Cary, North Carolina 27511
Voice 919 462 8474
Fax 919 462 8707
January 27, 2000
UNWATER
E C E I V E
0
JAN 312000 D
PROD # D 0347
1
1
1
1
1
1
TABLE
• Objective
• Methodology
• Results Summary
• Soil Types
• Open Channel Analysis
OF CONTENTS
• Outlet Design (Routing using Chain Saw Method)
• Hydrologic Calculations
OBJECTIVE
The "Country Inn Suites" site was examined to determine the hydrologic runoff from the site for
the purpose of designing a storm water detention basin This report summarizes the
' hydrologic methodology used in providing an estimated rate of stormwater runoff from the site
as a function of time and the design of the stormwater detention basin
t GENERAL
' • The proposed project will consist of a single 6-story building The project will have a total
of 12,870 square feet of gross building area and approximately 36,800 square feet of
pavement
• The proposed project will have storm water detention by utilizing the detention basin at the
rear of the site This basin will be sized to accommodate development on the adjoining lot
(Lot 1) with an assumed impervious development of 70%
• The drainage area consists of 3 15 acres (see attached page) The on -site drainage is
' 70 1 % (2 21 acres) of the total drainage area
• The Forebay is approximately 20% of the required volume The Forebay is the same depth
as the permanent pool
' • The vegetated shelf is located below permanent pool at a width of 10'
' There is no decorative fountain in this basin
• The chart used for TSS removal is 90% There is no 30-foot vegetative buffer
• This is not an infiltration system
IHYDRAULICS
' To model the drainage basin a pond was designed in accordance with both City of
Wilmington and North Carolina Department of Environment and Natural Resources design
requirements The inflow hydrograph was formulated by using the City of Wilmington
1 standards (see City of Wilmington Technical Standards, page 5-50) The basin was then
analyzed using Chainsaw Routing per the City of Wilmington preferred method (Storm
' duration of 6 hours and a precipitation depth of 4 8" & 6 4" for the 10-yr and 50-yr event,
respectively) The resulting spreadsheets were printed
1
I
' METHODOLOGY
t The inflow hydrograph was created by using the Rational Method to estimate peak flow Then
an estimate of the volume of runoff and the required storage was found (see City of
Wilmington Technical Standards, pages 5-50 through 5-54) Stage storage and stage
discharge were formulated and the basin was routed using Chainsaw Routing The site was
analyzed for both the 10-year and 50-year hydrologic event
1
LI
1
I
Off site drainage on to the site was routed through the site in an engineered channel
Calculations for this channel were completed by using the SoftDesk Hydrology package to
analyze trapezoidal channels Flow into the channel was found by delineating the watershed,
assigning a Rational "C" value to the various land sections and using the Rational Method to
find a peak flow (Q) at the point of interest The "C" value was assigned based on the final
built -out condition reflecting City zoning standards
RESULTS SUMMARY
• Total drainage area = 3 15 acres
On -site drainage area = 2 21 acres
• Surface area required = 5,315 ftz
Surface area provided = 5,692 W
• Volume required to detain first 1 " of runoff = 7,775 ft3
Volume provided to detain the first 1 " of runoff = 9,763 ft3
• The basin will drain the first 1 " of runoff in 2-5 days (see attached design basis)
• The basin will use an outlet weir to discharge more than the first 1 " of runoff
• The basin will be 6' deep (see calculations)
• Pre-existing flow from site for 10-year event = 7 43 CFS
• Developed peak run-off for 10-year event without storm water detention = 16 56 CFS
• Developed peak run-off for 50-year event without storm water detention = 22 35CFS
• Developed peak run-off for the 10-year event routed through the basin = 7 40 CFS
• Developed peak run-off for the 50-year event routed through the basin = 18 83 CFS
I
I
HYDROLOGIC SOIL TYPES
Since the exact soil type is not known, it is assumed the hydrologic soil type is type "D",
reflecting saturated conditions Type "D" is the type of soil that is the slowest to drain
The existing drainage basin (3 1 acres) is composed of a hotel and an undeveloped out
parcel The hotel is assumed to be impervious except for the traffic islands and landscaping
' The out parcel is thickly wooded but is assumed to have a build out of 70% impervious area
In formulating the SCS curve number a curve number of 93 was used The City of Wilmington
' shows in their stormwater management chapter (Chapter 5, p 5-52) that a commercial area
with roughly 72% impervious area and a "D"-type soil will have a SCS curve number of 93
' OPEN CHANNEL ANALYSIS
' The engineered channel conveying offsite drainage through the site will convey the 10-year
storm flow The channel will be lined with gabions, providing 1 1 side -slopes The bottom of
' the channel will be 19' wide The vertical slope in the channel is 0 22% The velocity in the
channel at full flow is 4 67 fps For further detail see the attached "Drainage Basin
Characterization/Channel Design"
OUTLET DESIGN
' The designed outlet for this basin is a 10' weir This weir will be placed as to retain the first 1 "
' (per NCDENR requirements) and help retain for the 10-year storm Any flow in excess of the
10-year event will leave the basin both through the outlet weir but also through the emergency
spillway, located above the 10' outlet weir The spillway will pass the 50-year event The
' retained 1 " of storm water will draw down in a 2-5 day period per NCDENR requirements
PI
1
' HYDRAULIC CALCULATIONS
' WET DETENTION POND
DESIGN BASIS
NCDENR
Drainage Area = 3 15 Acres (including 0 94 acres off site)
' Impervious Area = 95,752 sq ft
Percent Impervious (1) = 69 8% [(95,752/(3 15*43,560))* 1001
' Use a 6 foot deep pond, 90% TSS (no vegetated filter required), SA/DA =3 9
' Minimum Required Surface Area At Permanent Pool
= 0 039 * 3 15 Acres = 5,351 sq ft
Minimum Required Volume (Simple Method by Schueler)
' Rv = 0 05 + 0 009 (69 8) = 0 68
Volume = (1 "/12") * 0 68 * 3 15 * 43,560 = 7,775 cu ft
�I
Surface Area Provided at Perm Pool = 5,692 sq ft (>5,351), (Elev = 36')
Need at least 7,775 cu ft of storage (7,775 / 5,692 = 1 36'), use 1 5'
Set elevation of Temporary Pool = 36 + 1 5 = 37 5'
Surface Area at 37 5' = 7,325 sq ft
Surface Area at 37 95' = 7,973 sq ft (37 95' is used as temporary pool elevation in
accordance with City of Wilmington design procedures & routing)
Volume Provided = [(5,692 + 7,325)/21 * (37 5 — 36) = 9,763 cu ft (>7,775)
Forebay Volume
Permanent Pool Volume = 13,596 cu ft
Forebay Volume Required = 0 2*13596 = 2,719 cu ft
Forebay Volume Provided = 2,701 cu ft (6' deep forebay)
Orifice Sizing
Q2 = 7775/172800 = 0 045 CFS (Flowrate required for 2 day drawdown)
Q5 = 7775/432000 = 0 018 CFS (Flowrate required for 5 day drawdown)
Choose a 1" circular orifice, average head = (1 5'-(1/2)(2"/l2))/2 = 0 709'
Area = 0 00545 sq ft Q = CDA*Sgrt(2gh) = 0 025
(0 018<0 025<0 045)
1
IThe following pages are the design basis & criteria for The City of Wilmington
1 Please note Both weir calculations used flow exiting the basin, once routed
1
1
1
1
11
1
1
1
1
I�
1
1
1
1
1
1
1
1
1
Job Name - Country Inn Suites
Date - Jan 12, 2000
PRE -DEVELOPMENT
Watershed Area =
Hydraulic Length =
Hydraulic Height =
Runoff Coefficient =
Kirpich K Multiplier =
Time of Concentration =
Intensity =
Qa is predeveloped runoff
Qa =
COMPUTE DEPTH OF RUNOFF
WATERSHED DATA
POST -DEVELOPMENT
3 15 Acres
Watershed Area =
3 15 Acres
600 Feet
Hydraulic Length =
600 Feet
4 Feet
Hydraulic Height =
4 Feet
035
Runoff Coefficient =
073
1
Kirpich K Multiplier =
02
741 Min
Time of Concentration =
500 Min
674
Intensity =
720
Qp is post development runoff
7 43 CFS
Qp =
16 56 CFS
P=
CN =
S = (1000/CN)-10
S=
Q* _ (P-0 2S)A2/(P+0 8S)
Q*=
4 82 in (10-yr, 6-hr precipitation)
91
099
3 81 in ( 10-yr, 6-hr runoff depth)
FIND THE REQUIRED VOLUME AND THE TIME TO PEAK
Vol = (Q*)*A
Vol = 43537 ftA3
Tp = Vol/(1 39*Qp)
Tp = 31 53 min
ESTIMATE PRELIMINARY STORAGE REQUIRED
S = (Qp - Qa)*Tp*1 39*60
S = 24007 ftA3
CALCULATE Ks AND b
Contour
Area
(sa R)
36
5692
365
6220
37
6765
375
7325
38
7902
382
12460
385
15560
39
18380
b=
Ks =
Pond Invert = 36 Feet
Volume
Total Volume
Stage
InS
InZ
Z est
cu tt
L #1
M
O
00
0
29780
2978
05
7 999
0
089
32463
62243
1
8 736
0 000
1 32
35225
97468
1 5
9 185
0 405
1 68
38068
13554
2
9 514
0 693
200
20362
15590
22
9 654
0 788
216
42030
19793
25
9 893
0 916
245
84850
28278
3
10 250
1 099
297
1 87
371483
Job Name - Country Inn Suites
Date -Jan 12, 2000
CHAINSAW METHOD FOR RISER
BARREL ROUTING
STORM DATA
Qp =
16 56 cfs
Tp =
31 53
dT =
4
BASIN DATA
NORMAL SURFACE AREA =
Ks = 371483
Pk Outflow =
740 cfs
b =
1 87
Pk Stage =
38 82 cfs
Zo =
36
Maximum Storage =
25741 cu ft
normal water elevation =
36
Number of orifices
1
Box weir length =
0
Dia =
1 in
Cw=
3
Inv =
36 ft
Zcr=
0
Weir Length =
10 ft
OUTLET PIPE
Inv =
3795 ft
Db =
0
Cd =
065
Emergency
Zi =
36
Spillway Length =
30 ft
Inv =
38 45 ft
ROUTING
1
2
3
4
5
6
7
TIME
INFLOW
STORAGE
STAGE
OUTFLOW
ORIFICE
WEIR
min
cfs
cu ft
(ft)
cfs
0
0
0
3600
000
000
000
35
0
0
3600
000
000
000
70
2
105
3615
001
001
000
105
4
510
3635
002
002
000
140
7
1376
3659
002
002
000
175
10
2808
3686
003
003
000
210
12
4843
3715
003
003
000
245
15
7445
3745
003
003
000
280
16
10510
3775
004
004
000
31 5
17
13877
3803
066
004
062
350
16
17218
3827
386
004
382
385
15
19782
3845
448
004
444
420
13
21915
3859
494
005
489
455
11
23546
3869
555
005
550
490
10
24690
3876
608
005
603
526
8
25412
3880
667
005
662
561
7
25741
3882
718
005
713
596
6
25730
3882
740
005
735
631
5
25471
3880
733
005
728
666
5
25053
3878
720
005
715
701
4
24511
3875
697
005
692
736
3
23887
3871
669
005
664
771
3
23209
3867
636
005
631
806
3
22502
3862
615
005
610
841
2
21755
3858
592
005
587
876
2
20983
3853
553
004
549
I
1
91 1
2
20228
3848
538
004
534
946
1
19449
3843
518
004
514
981
1
18666
3837
499
004
495
1016
1
17881
3832
469
004
465
1051
1
17123
3827
424
004
420
1086
1
16430
3822
389
004
385
1121
1
15783
3817
314
004
309
1156
1
15272
3813
237
004
233
1191
1
14902
3810
1 86
004
1 82
1226
0
14623
3808
1 50
004
146
1261
0
14405
3807
123
004
1 19
1296
0
14229
3805
1 03
004
099
1331
0
14085
3804
087
004
083
1366
0
13964
3803
075
004
071
1401
0
13861
3802
065
004
061
1436
0
13772
3802
056
004
052
1471
0
13694
3801
049
004
045
1506
0
13626
3801
043
004
039
1541
0
13565
3800
038
004
034
1577
0
13510
3800
034
004
030
1612
0
13461
3799
030
004
026
1647
0
13417
3799
027
004
023
1682
0
13377
3799
024
004
020
1717
0
13340
3798
022
004
018
1752
0
13307
3798
020
004
016
1787
0
13276
3798
018
004
014
1822
0
13248
3798
016
004
012
1857
0
13222
3797
015
004
Oil
1892
0
13198
3797
014
004
010
1927
0
13175
3797
012
004
008
1962
0
13155
3797
Oil
004
007
1997
0
13135
3797
010
004
006
2032
0
13117
3797
010
004
006
2067
0
13101
3796
009
004
005
2102
0
13085
3796
008
004
004
2137
0
13070
3796
008
004
004
2172
0
13057
3796
007
004
003
2207
0
13044
3796
007
004
003
2242
0
13031
3796
006
004
002
2277
0
13020
3796
006
004
002
2312
0
13009
3796
006
004
002
2347
0
12998
3796
005
004
001
2382
0
12988
3795
005
004
001
2417
0
12979
3795
005
004
001
2452
0
12969
3795
005
004
001
2487
0
12960
3795
004
004
000
2522
0
12952
3795
004
004
000
2557
0
12944
3795
004
004
000
2592
0
12935
3795
004
004
000
2628
0
12927
3795
004
004
000
2663
0
12919
3795
004
004
000
2698
0
12911
3795
004
004
000
2733
0
12903
3795
004
004
000
tmpftl.txt
Weir Calculator
Given Input Data
Weir Type ........
..... Cipolleti
Solving for ...
...... Depth of Flow
Flowrate
.......... . 6.0000 cfs
Cv .........
0 5500
Cd ........
......... 0 6300
Height .........
6.0000 in
Computed Results.
Depth of Flow ....
. . .... 5.5725 in
Full Flow
......... 6 7035 cfs
Velocity ........
. 1.2772 fps
Crest length ..
........ 122 7863 in
Width ............
120.0000 in
Area .......
. .... 5.0625 ft2
Perimeter
........... 132 3693 in
Wet Perimeter ....
.... 131 4880 in
Wet Area ....
........ 4 6977 ft2
Percent Full
........ ... 92.8750 %
Page 1
Job Name - Country Inn Suites
Date -Jan 12, 2000
PRE -DEVELOPMENT
Watershed Area =
Hydraulic Length =
Hydraulic Height =
Runoff Coefficient =
Kipich K Multiplier =
Time of Concentration =
Intensity =
Qa is predeveloped runoff
Qa =
COMPUTE DEPTH OF RUNOFF
WATERSHED DATA
POST -DEVELOPMENT
3 15 Acres
Watershed Area =
3 15 Acres
600 Feet
Hydraulic Length =
600 Feet
4 Feet
Hydraulic Height =
4 Feet
035
Runoff Coefficient =
073
1
Kirpich K Multiplier =
02
741 Min
Time of Concentration =
500 Min
674
Intensity =
972
Qp is post development runoff
7 43 CFS
Qp =
22 35 CFS
P=
CN =
S = (1000/CN)-10
S=
Q' _ (P-0 2S)A2/(P+0 8S)
Q. =
6 4 in ( 50-yr, 6-hr precipitation)
91
099
5 35 in ( 50-yr, 6-hr runoff depth)
FIND THE REQUIRED VOLUME AND THE TIME TO PEAK
Vol = (Q')'A
Vol = 61165 ftA3
Tp = Vol/(1 39•Qp)
Tp = 32 81 min
ESTIMATE PRELIMINARY STORAGE REQUIRED
S = (Qp - Qa)'Tp'1 39*60
S = 40841 ftA3
CALCULATE Ks AND b
Contour
Area
(sa ft)
36
5692
365
6220
37
6765
375
7325
38
7902
382
12460
385
15560
39
18380
b=
Ks =
Pond Invert = 36 Feet
Volume
Total Volume
Stage
InS
InZ
Z est
(Cu fr
cu M
M
L!
00
0
29780
2978
05
7 999
0
089
32463
62243
1
8 736
0 000
1 32
35225
97468
1 5
9 185
0 405
168
38068
13554
2
9 514
0 693
200
20362
15590
22
9 654
0 788
216
42030
19793
25
9 893
0 916
245
84850
28278
3
10 250
1 099
297
1 87
371483
17
C
1
t
1]
11
Job Name - Country Inn Suites
Date -Jan
12, 2000
CHAINSAW METHOD FOR RISER
BARREL
ROUTING
STORM DATA
Qp =
22 35 cfs
Tp =
31 53
dT =
4
BASIN DATA
NORMAL SURFACE AREA =
Ks =
371483
Pk Outflow =
1883 cfs
b =
1 87
Pk Stage =
3868 cfs
Zo =
36
Maximum Storage =
23442 cu It
normal water
elevation =
36
Number of orifices
1
Box weir length =
0
Dia =
1 in
Cw=
3
Inv =
36 ft
Zcr =
0
Weir
Length =
10 ft
OUTLET PIPE
Inv =
37 95 It
Db =
0
Cd =
065
Emergency
Zi =
36
Spillway
Length =
30 ft
Inv =
38 45 ft
ROUTING
1
2
3
4
5
6
7
TIME
INFLOW
STORAGE
STAGE
OUTFLOW
ORIFICE
WEIR
min
cfs
cu ft
M
Ids)
0
0
0
3600
000
000
000
35
1
0
3600
000
000
000
70
3
142
3617
001
001
000
105
6
688
3641
002
002
000
140
9
1858
3669
002
002
000
175
13
3793
3701
003
003
000
21 0
17
6542
3735
003
003
000
245
20
10056
3770
004
004
000
280
22
14195
3805
099
004
095
315
22
18542
3837
808
004
803
350
22
21542
3856
1445
005
1441
385
20
23062
3866
1794
005
1789
420
17
23442
3868
1883
005
1879
455
15
23086
3866
1800
005
1795
490
13
22421
3862
1645
005
1641
526
11
21661
3857
1472
005
1468
561
10
20902
3852
1303
004
1299
596
8
20185
3848
1147
004
1143
631
7
19523
3843
1007
004
1003
666
6
18920
3839
883
004
879
701
5
18374
3835
775
004
770
736
5
17880
3832
679
004
675
771
4
17434
3829
596
004
591
806
3
17032
3826
523
004
519
841
3
16669
3823
459
004
455
876
3
16340
3821
403
004
399
I
I
t
11
t
1
91 1
2
16043
3819
355
004
351
946
2
15774
3817
312
004
308
981
2
15531
3815
275
004
271
101 6
1
15310
3813
243
004
238
1051
1
15109
3812
214
004
210
1086
1
14927
3811
1 89
004
1 85
1121
1
14761
3809
167
004
163
1156
1
14610
3808
1 48
004
1 44
1191
1
14472
3807
1 31
004
1 27
1226
1
14347
3806
1 16
004
1 12
1261
1
14232
3805
103
004
099
1296
0
14128
3804
092
004
088
1331
0
14032
3804
082
004
078
1366
0
13945
3803
073
004
069
1401
0
13865
3802
065
004
061
1436
0
13791
3802
058
004
054
1471
0
13724
3801
052
004
048
1506
0
13662
3801
047
004
043
1541
0
13605
3800
042
004
038
1577
0
13553
3800
037
004
033
1612
0
13505
3800
034
004
030
1647
0
13461
3799
030
004
026
1682
0
13420
3799
027
004
023
171 7
0
13382
3799
025
004
021
1752
0
13347
3798
022
004
018
1787
0
13315
3798
020
004
016
1822
0
13285
3798
019
004
015
1857
0
13257
3798
017
004
013
1892
0
13231
3797
015
004
Oil
1927
0
13207
3797
014
004
010
1962
0
13185
3797
013
004
009
1997
0
13164
3797
012
004
008
2032
0
13145
3797
Oil
004
007
2067
0
13127
3797
010
004
006
2102
0
13110
3796
009
004
005
2137
0
13094
3796
009
004
005
2172
0
13079
3796
008
004
004
2207
0
13065
3796
007
004
003
2242
0
13051
3796
007
004
003
2277
0
13039
3796
006
004
003
2312
0
13027
3796
006
004
002
2347
0
13015
3796
006
004
002
2382
0
13005
3796
005
004
001
2417
0
12994
3796
005
004
001
2452
0
12985
3795
005
004
001
2487
0
12975
3795
005
004
001
2522
0
12966
3795
004
004
001
2557
0
12958
3795
004
004
000
2592
0
12949
3795
004
004
000
2628
0
12941
3795
004
004
000
2663
0
12933
3795
004
0 04
000
2698
0
12925
3795
004
004
000
2733
0
12917
3795
004
004
000
t
1
1
1
1
1
1
tmp#1 txt
Weir Calculator
Given Input Data
Weir Type ...... .......
Cipolleti
Solving for . .....
Depth of Flow
Flowrate ...........
15.0000 cfs
Cv . ......... .....
0.5500
Cd ........... .........
0 6300
Height .........
6.0000 in
Computed Results
Depth of Flow .........
4.9878 in
Full Flow ..... ......
19 7905 cfs
Velocity ..... ........
1.1988 fps
Crest length ......... . ...
362.4939 in
Width .......... . . .......
360 0000 in
Area ........... ........
15.0625 ft2
Perimeter ........ ..
372.3693 in
Wet Perimeter .. .......
370 2826 in
Wet Area .... .........
12 5127 ft2
Percent Full . ........ ..
83.1298 a
Page 1
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Chhabra — Wilmington
Drainage Basin Characterization/Channel Design
January 27, 2000
After examining aerial photographs of the watershed, certain assumptions were made
about the drainage patterns that reduced the watershed area to 125 acres (down from
the original 157 acres) The assumptions are as follows
1 The drainage from the south side of Smith Creek Parkway does not cross to the
north side of the Parkway until it is further downstream than our site
2 The RB-zoned area in the northwest region of the watershed is treated in a wet
basin (revealed by aerial photography) and then flows toward Market Street
Additionally, land use characterizations in the upper portions of the watershed were
reexamined It is assumed the City of Wilmington will make all future development
release storm water at a rate no more than the pre -developed conditions The key
assumption here is that after storm water detention, the post -developed flow from a
site is 90% of the pre -developed flow The entire recharactenzation enabled the
inflow to be reduced from 246 cfs to the current inflow of 134 cfs Below is a
summary of calculations
Land Use
Delineated Watershed area = 124 96 acres
Existing Conditions Golf Course = 20 66 acres
Single Family Homes = 24 79 acres
Wooded area (zoned R-10) = 51 65 acres
Homes on Golf Course = 6 89 acres
Lightly developed land along Parkway = 21 03 acres
Assign "c" value for each land use
Golf Course = 0 10
Wooded land = 0 20
Lightly developed area = 0 50
Golf Course Homes = 0 35
Single Family Homes = 0 45
Find weighted "c" value
' Golf Course = (20 66/124 99)*(0 10) = 0 0165
Wooded Land = (51 65/124 9)*(0 20) = 0 0827
Lightly developed land = (21 03/124 96)*(0 50) = 0 0842
' Homes on the Golf Course = (6 89/124 96)*(0 35) = 0 0193
Single Family Homes = (21 03/124 96)*(0 45) = 0 0757
Weighted "c" value = 0 28
1
1
I
' Flow
Tc = [(L ^ 3/H) ^ 0 385]/128
Where L = Hydraulic Length = 3000 ft
H = Hydraulic Height = 50 2-36 = 13 8 ft
Tc = 29 51 min
We shall use 30 minutes for Time of Concentration
'
Now, find flow
Q'io = c*i*A
'
Where A = 125 acres
ho = 4 25 in /hr (30 min , 10-year intensity from Chart E-6)
c = weighted based on land use = 0 28 (down from 0 31)
'
Q'lo = (125)*(4 25)*(0 28)
Q',o = 149 cfs
'
Now, assume everyone upstream has storm water detention
'Q10—Q
09
134 ds
Q10 =
Similarly, fifty-year flow is checked
Q'so = (125)*(5 44)*(0 28)
' Q'sa = 190 cfs
Assuming storm water detention is required
' Q51=Q'*09
Qw = 171 ds
' The Channel Calculator for our proposed channel and the above -stated flows is
' attached Please note that the 10-year flow does not over -top the proposed channel,
satisfying City of Wilmington Standards
' We have also included HEC-RAS plots of flow in the proposed channel to aid in your
review
1
1
'
i0-YY FcoW 7MRouGN
C�iANNE�
tmp#l.txt
'
Channel Calculator
Given Input Data
Shape ............... ........ ..
Rectangular
'
Solving for ...... . . .......
Depth of Flow
Flowrate ........ ..............
134.0000 cfs
'
Slope .. ............ .........
Manning's n ...... ..............
0.0022 ft/ft
0 0200
Height . .......................
24.0000 in
'
Bottom width ....................
Computed Results.
228.0000 in
'
Depth ...........................
Velocity
19.5128 in
4.3372 fps
Flow area ........
30.8952 ft2
Flow perimeter . ...............
Hydraulic radius .
267.0256 in
16.6610 in
Top width .. ..........
228.0000 in
Area ............ ......... ....
38.0000 ft2
Perimeter ...... ............ ...
276.0000 in
Percent full
81 3032 %
Critical Information
Critical depth
13.8754 in
Critical slope ....... ..........
0 0065 ft/ft
'
Critical velocity ... ..........
Critical area
6.0994 fps
21.9695 ft2
Critical perimeter ............ .
255.7509 in
Critical hydraulic radius .
Critical top width .....228.0000
12.3699 in
in
Specific energy ......... ......
1.9184 ft
Minimum energy ............ ...
Froude number ...................
1.7344 ft
0.5996
Flow condition ........... ......
Subcritical
Page 1
' So- YR, Ftovy 7}•1RoV( m G44„ 46 L
' tmp#l.txt
'
Channel Calculator
Given Input Data:
Shape . ............... .. ..
Rectangular
Solving for
Depth of Flow
Flowrate .............. .........
171.0000 cfs
Slope ........... .. . .....
0 0022 ft/ft
Manning's n ... . ........... ...
0 0200
Height ...................... ...
24.0000 in
'
Bottom width . ... .......... .
228.0000 in
Computed Results*
Depth ..
22 8081 in
'
Velocity ....... . •.••••.•••
4.7352 fps
Flow area ... ............. ...
36.1129 ft2
Flow perimeter ........... . ...
273.6162 in
'
Hydraulic radius .......... .
19.0056 in
Top width ........ . ..........
228 0000 in
Area .. ........ ...............
38.0000 ft2
Perimeter ....... ...........
276.0000 in
'
Percent full ................
95.0338 %
Critical Information
'
Critical depth .
16.3246 in
Critical slope . ............ .
0.0063 ft/ft
Critical velocity ........ ..
6.6158 fps
'
Critical area ....... . .....
25 8472 ft2
Critical perimeter ... . .......
260 6491 in
Critical hydraulic radius
14.2797 in
'
Critical top width .......
228.0000 in
Specific energy ..... . ... .....
2.2491 ft
Minimum energy ....... .. ......
2.0406 ft
'
Froude number ..................
0.6055
Flow condition . ............
Subcritical
11
1
Page 1
1
1
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1
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39
m
I
37
37
36
36
i 02
Chaabra_Wilmington
West Boundry Line
02 +02
50-yr Flood
1 Qyr Flood
■
Ground
Bank Sta
0 20 40 60 80 100
Station (ft)
1
1
1
1
1
1
1
39
w
m
37
37
36
W
Chaabra Wilmington
02 -- — 02 —+— 02 —�
50-yr Flood
10-yr Flood
Ground
•
Bank Sta
0 20 40 60 80 100
Station (ft)
39
W
m
37
37
36
KI
Chaabra_Wdmington
i( 02 —( 02 —+ 02
50-yr Flood
10-yr Flood
■
Ground
•
Bank Sta
0 20 40 60 80 100
Station (ft)
1
1
1
t
1
39
5
m
37
37
36
Ki:
i 02
Chaabra_Wdmington
02 —+— 02 —�
50-yr Flood
10-yr Flood
■
Ground
•
Bank Sta
0 20 40 60 80 100
Station (R)
I
1
1
1
1
1
1
t
39
m
m
37
37
4
36
i 02
Chaabra_Wilmington
North Boundry Line
02 —i 02
50-yr Flood
I D-yr Flood
Ground
•
Bank Sta
0 20 40 60 80 100
Station (ft)
STORIA01 °ATER
I&, �ECEIVEI
RICE & ,JAN 3 12000 D
ASSOCIATES
D E M
PAOJ N—_
January 17, 2000
Ms Linda Lewis
NCDENR
Wilmington Regional Office
Water Quality Section
127 Cardinal Drive Extension
Wilmington, North Carolina 28405
Re SW8 990847
Wilmington, NC
New Hanover County Request for Additional Information
Dear Ms Lewis
Rice & Associates is submitting the attached set of calculations in response to your request
of January 4, 2000 for the above referenced project The following items address the staff
comments and provide the necessary additional information to complete the technical
review process The following responses are numbered per the staff comments
1 Please find the attached set of signed and sealed calculations incorporating revised
pond design criteria
2 The total BUA for this project is 95,752 sq ft , and we acknowledge the change you
made to expedite the review
3 We acknowledge the fact you changed page 3 of the application to show the BUA for
lotl and lot 2 separately
4 Surface area at elevation 37 95' is 7,973 sq ft This number is also listed in the
calculations
5 The drawdown has been redesigned to function within the 2-5 day requirements
6 The dimensions for the permanent pool elevation (36') are now listed on sheet C-1
7 The word "Spillway has been moved and reads more clearly on the plans
8 The pond storage elevation now is labeled as 37 95'
116 New Edition Court • Cary, North Carolina 27511 • Voice 919 462 8474 • Fox 919 462 8707 . [moil riceassoaates@telix cam
�a
Stormwater Project No SW8 990847
Request for Additional Information
January 17, 2000
Should you have any other questions or comments, please advise
Very truly yours,
RICE & ASSOCIATES
Ted Credle
CC Gary Chhabra, JSS Wilmington, LLC
State of North Carolina
Department of Environment
and Natural Resources
Wilmington Regional Office
James B. Hunt, Jr., Governor
Bill Holman, Secretary
Division of Water Quality
January 4, 2000
Mr G S Chhabra, Manager
JSS Wilmington, LLC
104 Brittany Place
Cary, NC 27511
1�
NCDENR
NORTH CAROLINA DEPARTMENT OF
ENVIRONMENT AND NATURAL RESOURCES
Subject ACKNOWLEDGMENT OF RECEIPT AND
REQUEST FOR ADDITIONAL INFORMATION
Stormwater Project No SW8 990847
Country Inn Suites Hotel
New Hanover County
Dear Mr Chhabra
The Wilmington Regional Office received a Stormwater Management Permit Application for Country
Inn Suites Hotel on December 2, 1999 A preliminary review of that information has determined that the
application is not complete The following information is needed to continue the stormwater review
Please provide revised, signed and sealed design calculations which address the revised pond
design criteria Please include surface areas at permanent and temporary pools, volumes, SA/DA
ratio, impervious areas, drainage area, elevations, onfice size and drawdown, etc
The total BUA requested for this site on page 2 of the application must include Lot I The total
BUA for both Lots 1 and 2 is 95,752 112, not 67,089 For purposes of speeding up the process,
I have taken the liberty of making the change on the application Please review the enclosed
copy and provide wntten acceptance of the changes
The built -upon areas for Lots 1 and 2 need to be individually limited on page 3 of the
application Again, to speed this up, I have taken the liberty of making the change Please review
and provide wntten acceptance of the changes The permit will require that a deed restriction
which limits the built -upon area to 28,663 ft2 be recorded prior to the sale of Lot 1
Please include the surface area at elevation 37 95 in the calculations
The six inch diameter onfice will drawdown the pond in about 2 4 hours The rules require a
2-5 day drawdown As previously explained, the onfice size is based only on the required 1"
runoff volume (=7,750 cubic feet by Schueler's method, =7,980 cubic feet by the Rational
method) Please decide on a method to determine the 1 " volume and revise the onfice size on
the wet pond supplement I have included an example calculation sheet that was used at our
workshops last year
6 The dimensions provided for the pond appear to be for the 38 contour Please provide
dimensions for the permanent pool contour, 36 Please label the 36 contour on sheet C-1
127 Cardinal Dr Ext, Wilmington, North Carolina 28405 Telephone 910-395-3900 FAX 910-350-2004
An Equal Opportunity Affirmative Action Employer 50% recycled/10% post -consumer paper
Mr Chhabra
January 4, 2000
Stormwater Project No SW8 990847
The words "Spillway" have been mostly obliterated by the shaded square Much represents the
spillway Pleas clearly label the spillway/outlet
The pond section detail labels the storage elevation as 36 8', when in fact it is 37 95 Please
relabel as 37 95, unless you want to revise the storage elevation to 36 8
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 February 4, 2000, or the application will be
returned as incomplete The return of a project will necessitate resubmittal of all required items, including the
application fee
If you need additional time to submit the information, please mail or fax your request for a time
extension to the Division at the address and fax number at the bottom of this letter The request must indicate
the date by which you expect to submit the required information. The Division is allowed 90 days from
the receipt of a completed application to issue the permit
The construction of any impervious surfaces, other than a construction entrance under an approved
Sedimentation Erosion Control Plan, is a violation of NCGS 143-215 1 and is subject to enforcement action
pursuant to NCGS 143-215 6A
Please reference the State assigned project number on all correspondence Any original documents that
need to be revised have been sent to the engineer or agent All original documents must be returned or new
originals must be provided Copies are not acceptable If you have any questions concerning ttus matter please
feel free to call me at (910) 395-3900
Sincerely, '/
//�� �%
Linda Lewis
Environmental Engineer
RSS/arl S \WQS\STORMWAT\ADDINFO\990847 JAN
cc Linda Lewis
Steven Rice, P E
127 Cardinal Dr Ext , Wilmington, North Carolina 28405 Telephone 910-395-3900 FAX 910-350-2004
An Equal Opportunity Affirmative Action Employer 50% recycled/10°/ post -consumer paper
9
KILL &
ASSOCIATES
November 30, 1999
Ms Linda Lewis
NCDENR
Wilmington Regional Office
Water Quality Section
127 Cardinal Drive Extension
Wilmington, North Carolina 28405
D E C E I V E
DEC 0 21999 D
D E M
PROJ q
Re SW8 990847
Wilmington, NC
New Hanover County Request for Additional Information
Dear Ms Lewis
Rice & Associates is submitting the attached set of calculations in response to your
request of October 26, 1999 for the above referenced project The following items
address the staff comments and provide the necessary additional information to
complete the technical review process The following responses are numbered per the
staff comments
1 The building dimensions are now shown on sheet C-1
2 The BUA was given on the form as requested (71 4%) However, it is now given as
both a percentage and an actual area on the attached form
3 The dimensions for each arc & side outlining the permanent pool are on sheet C-1
Additionally, the dimensions for the sheet pile and the forebay are shown on the plans
4 There are no wetlands on this site, as shown by the attached sketch provided by
Mitchell and Associates, Inc A note stating this has been added to sheet C-1
5 Turfstone parking area has been graded so that the runoff is collected and sent into
the foeeboy of the pond
6 The average flow depth of the pond is 0' The average flow elevation of this ditch is
36' This ditch is a wet weather ditch
116 New Edition Court • Cary, North Carolina 27511 • Voice 919 462 8474 • Fox 919 462 8707 • Email riceassociates@telex com
Stormwater Project No SW8 990847
Request for Additional Information
November 30, 1999
7 The orifice has been resized, the plans are revised and the forms are updated
8 The orifice tee is adequately dimensioned on the plans
9 The pond depth is 6' The detail has been revised to show this depth
10 Plantings and grasses for the 6 1 vegetated slope are specified on sheet D-1
11 No decorative fountain is planned or specified for this site A note on sheet C-1
states none can be used for this pond
12 Dimensions on this plan are to back of curb, as mentioned in the notes on sheet C-
1
13 The total Built -upon Area is listed on the form This area reflects both lots, which this
pond will service
14 The surface area at elevation 37 is 6,765 sq ft
15 All forms are revised and are enclosed
Should you have any other questions or comments, please advise
Very truly yours,
RICE & ASSOCIATES
J'J CJ' _
Ted Credle
CC Gary Chhabra, JSS Wilmington, LLC
Department of Environment
and Natural Resources
Wilmington Regional Office
James B. Hunt, Jr., Governor
Bill Holman, Secretary
Division of Water Quality
October 26, 1999
Mr G S Chhabra, Manager
JSS Wilmington, LLC
104 Brittany Place
Cary NC 27511
NCDENR
I`IORTN CAROLINA DEPARTMENT OF
ENVIRONMENT AND NA uRAL RFSOURCE5
Subject ACKNOWLEDGMENT OF RECEIPT AND
REQUEST FOR ADDITIONAL INFORMATION
Stormwater Project No SW8 990847
Country Inn Suites Hotel
New Hanover County
Dear Mr Chhabra
The Wilmington Regional Office received a Stormwater Management Permit Application for Country
Inn Suites Hotel on August 24, 1999 A preliminary review of that information has determined that the
application is not complete The following information is needed to continue the stormwater review
Please provide the building dimensions on the plans
2 Please provide the BUA limit for each Lot on page 3 of the application, Section IV, Deed
Restriction Number 2 Please complete and return the original Copies are not acceptable
Please provide the dimensions for each side and are of the figure created by the permanent pool
contour, on the plans Please also providea dimension to indicate how far the sheet pile wall is
to be located out into the pond in order to accurately provide the required 20% storage
Additionally, the supplement reports that only 7,191 square feet of surface area is provided at
elevation 36, however, my scaling indicates that over 8,100 square feet is provided The surface
area on the supplement should reflect what is being provided Please check and revise the
supplement, plans and/or calculations as needed
4 Delineate all wetlands on site, or note on the plans that none exist
Please grade the turfstone parking area such that the runoff is collected and directed into the
forebay of the pond Even though this area may be considered pervious by the City, it is
considered an impervious surface by the State and its runoff must be treated in the pond
What is the anticipated average flow depth in the proposed ditch? If it is anywhere above 36,
the pond will not be able to drawdown within the required 2 days, and subsequent violations of
the permit maintenance requirements may result, as well as flooding problems
127 Cardinal or Est, Wilmington, North Carolina 28405 Telephone 910-395-3900 FAX 910-350-2004
An Equal Opportunity Affirmative Action Employer 50% recycled/10% post -consumer paper
--
Mr Chhabra
October 26, 1999
Stormwater Project No SW8990847
The orifice size must be based on passing the required minimum volume, or approximately
7,800 cubic feet, and using the average head from the storage elevation to the centerline of the
orifice The calculations indicate that a volume of 10,817 cubic feet is being used as the
beginning volume (the supplement indicates that the storage volume is 9,042 cubic feet) and that
the elevation above the outlet is 3' The average head to the center line of the orifice is 46', not
3' Please revise and resize the orifice
Please adequately dimension the orifice tee How far below the surface will the tee extend? How
far above the permanent pool will it extend? Maintenance is a concern due to the type of orifice
being proposed To cut down on the clogging potential, please specify a larger outlet pipe with
the appropriately sized orifice tee (see comment #7) To facilitate maintenance, please provide
some type of support and a way to easily access the orifice to check and clear it
The detail indicates that the pond depth in the forebay area is 4 6% but the elevations indicate
that the depth is 5' Please clarify and revise
10 Please specify the type of plantings to be used on the 6 1 vegetated shelf, and specify the grass
cover for the pond slopes on the detail
11 Decorative spray fountains are prohibited Do not specify or construct a fountain in this pond,
or you will be considered in violation of the permit and subject to enforcement action
12 Are the dimensions provided to the face of the curb, or the back of the curb? Please note on the
plans
13 Please include the Built -upon area for Lot 1 in the highlighted column on the application This
pond is designed to include both Lot 1 and 2, so the application must reflect the total BUA being
requested, 95,752 square feet
14 Please report the surface area provided at elevation 37 In order to provide 9,042 cubic feet at
elevation 37, you must provide a minimum of 10,985 square feet of surface area at elevation 37
According to my scaling, only 9,600 square feet is provided Please check and revise the
supplement as needed
15 Please revise and return all original forms enclosed with this letter Copies are not acceptable
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 November 26, 1999, or the application will
be returned as incomplete The return of a project will necessitate resubmittal of all required items, including
the application fee The Division is allowed 90 days from the receipt of a completed application to issue the
permit
The construction of any impervious surfaces, other than a construction entrance under an approved
Sedimentation Erosion Control Plan, is a violation of NCGS 143-215 1 and is subject to enforcement action
pursuant to NCGS 143-215 6A
Mi Chhabia
October 26, 1999
Stormwater Project No SW8 990847
Please reference the State assigned project number on all correspondence If you have any questions
concernmg this matter please feel free to call me at (910) 395-3900
Sincerely,
Linda Lewis
Environmental Engineer
RSS/arl S \WQS\STORMWAT\ADDINFO\990847 OCT
cc Linda Lewis
Ted Credle
LETTER
RICE &
ASSOCIATES
TO Ms LiNOA LEtvis
c' DENR
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WtLMJAJ6&TDn1 Al 28g05
AUG 2 4 1999
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DATE A UG . 20 1999
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SENDING XAttached ❑Under Separate Cover OVia US Mail )WOvemight UPS/Fed Ex ❑Messenger OTo Be Picked Up By Recipient
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COMMENTS
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COPYTO SENT BY T CREOLE
116 New Edition Court • Cary, North Carolina 27511 • Voice 919 462 8474 -Fax 919 462 8707 • Email nceassociates@teitx com
RICE & ASSOCIATES
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201c9 10161
P ea, C;�S 14 D-0 • UD
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COUNTRY INN SUITES HOTEL
NEW HANOVER COUNTY, NORTH CAROLINA
301 Eastwood Road
Wilmington, North Carolina
2 21 Acres
HYDROLOGY & HYDRAULIC CALCULATIONS
JSS WILMINGTON, LLC
104 BRITTANY PLACE
CARY, NORTH CAROLINA 27511
919 - 481 - 1200
prepared by ST®RM tl tl ATE R
' D E C E I V E
AUG 2 41999
PROS N o 11
RICE &
ASSOCIATES
116 New Edition Court
Cary, North Carolina 27511
Voice 919 462 8474
Fax 919 462 8707
S
2251t ti;
August 13,1999
= N :
TABLE OF CONTENTS
• Surface Area provided for permanent and design pool
• Orifice sized to pass the volume in the pond in 2-5 days
• Forebay is approximately 20% of the required volume Forebay is the same depth as the
permanent pool
• Vegetated shelf located below permanent pool at a width of 10'
• There is decorative fountain m this basin
• The chart used for TSS removal is 90% There is no 30 foot vegetative buffer
• This is not an infiltration system
HYDRAULIC CALCULATIONS
Desian Reauirements & Calculations
In order to ascertain the required surface area and volume, the appropriate SA/DA ratio must
be found To do this we first find the total site impervious percentage
Lot 1 has a total drainage area of 0 94 acres Lot 1 is assumed to be developed and be 70%
impervious
Lot 2 has a total drainage area of 2 21 acres Lot 2 was designed to have 67,089 ft2 of
impervious area or 71 4% ('M1
Total drainage to the basin is 3 15 acres
A weighted %impervious can be found
2 21 (71 4) + 0 94 70 = 70 98%
315 315
Due to site constraints there will be no 30' vegetative buffer, so the basin must be designed to
remove 90% TSS
Surface Area Design
Since we know the site is 70 98% impervious, how much surface area do we need2
1 At 4 5' deep, interpolate for 70 98% impervious
64— x = 80-7098
64-55 80-70
x=559
SA, d = (SA/DA)*(Drainage area)
_ (5 59/100)*(3 15)'(43560)
= 7670 ft2
This surface area is too large for to fit on the site We must choose a deeper basin
2 At 5 0' deep
57— x = 80-7098
57-50 80-70
x=507
SAfegd = (SA/DA)*(Drainage area)
= (5 07/100)*(3 15)*(43560)
= 6957 ft2
This site can use up to 7191 ft' for surface area, so this depth is appropriate
This basin's normal pool will be 5 feet deep
Volume Design
Required Volume Rv = 0 05 + 0 009 * (%Impervious)
%Impervious = 71 4
Rv = 0 05 + 0 009 * (71 4)
Rv = 0 6926
solve for required volume,
1" * (1712") * 3 15acres * 43560ft2/acre * 0 6926 = 7920 ff
85% TSS REMOVAL
30 FOOT VEGETATED FILTER REQUIRED
DEPTH
3'
3 5'
4 0'
4 5'
5 0'
5 5'
6 0'
6 5'
7 0'
7.5'
IMP %
10%
9
8
7
6
5
0
0
0
0
0
20%
1.7
13
12
11
10
9
8
7
6
5
30%
25
22
19
18
16
15
13
12
10
.9
40%
34
30
2.6
24
21
19
16
14
11
10
50%
42
37
3.3
30
27
24
21
18
1.5
1.3
60%
50
45
38
35
32
2.9
26
23
20
16
70%
60
52
45
41
37
331
29
25
21
18
80%
68
6.0
52
47
42
3.7
32
27
22
20
90%
75
65
58
53
48
43
38
33
28
13
100%
82
74
68
62
56
5.0
T4.4
38
32
26
90% TSS REMOVAL
NO VEGETATED FII.TER REQUIRED
DEPTH
3'
3 5'
4 0'
4.5'
50,
5.5'
6 0'
6 5'
7 0'
7 5'
D� %
10%
13
10
8
7
6
5
.4
3
2
1
20%
24
20
18
17
15
14
12
10
9
6
30%
35
30
2.7
25
22
1.9
16
13
11
8
40%
45
40
35
31
28
25
21
18
14
1.1
50%
56
50
43
39
35
31
2.7
23
19
15
60%
70
60
53
48
4.3
3.9
34
29
24
1.9
70%
81
70
60
55
50
45
39
34
29
23
80%
94
80
70
64
57
52
46
40
34
28
90%
107
90
79
72
65
59
5.2
46
39
143
33
100%
120
100
88
81
73
66
58
51
36
Note: The required surface area calculated from the tables is to be provided at the permanent pool elevation.
U rev iU-31-
Z, I
Discharge
(cls)
PeekR
Penod
Velocry
Qps)
Mee
(sq R)
Hydraulic
Redius(fl)
Normal
DepthM
160
1 30
1 181
1 885
1 066
1 077
20 Wi [Mbo08 20
Not to Scale
Reach
Sod Type
Mennmg's
Permissible
Calculated
Safety
Remarks
Straight
C350
2
0 044
450
024
1880
STABLE
Stnple E
Detain
1
NORTH AMERICAN GREEN EROSION CONTROL MATERIALS DESIGN SOFTWARE VERSION 4 1
NORTH AMERICAN GREEN CHANNEL PROTECTION - ENGLISH/S I
USER SPECIFIED CHANNEL LINING BACK-UP COMPUTATIONS
PROJECT NAME Chhabra hotel - Wilmington PROJECT NO 99 055
COMPUTED BY T Credle DATE 8/12/1999
FROM STATION/REACH TO STATION/REACH
DRAINAGE AREA 3 15 acres DESIGN FREQUENCY
INPUT PARAMETERS
----------------
Channel Discharge
16 Oafs ( 45 m^3/s)
Peak Flow Period
3 hours
Channel Slope
0 005 ft/ft (0 005 m/m)
Channel Bottom Width 10 0 ft (3 05 m)
Left Side Slope
21
Right Side Slope
21
Channel Lining C350 Staple E
Permi Shear(Tp) 4 50 psf (215 5 Pa)
Phase = 2
***int***i**
CALCULATIONS
Intial Depth Estimate = 0 16*(16 0 /(0 005^0 5))^0 375 = 1 22 ft (37 m)
Final Channel Depth (after 10 iterations) = 77 ft (0 23 m)
Flow Area = (10 0 * 0 8)+(0 5 *0 77A2 * (2 0+2 0)) = 8 8 sf (0 8 MA 2)
Wet Per =10 0 +(0 8*(((2 0^2)+1)A 5 +((2 0^2)+1)A 5)) = 13 4 ft (4 1 m)
Hydraulic Radius = (8 8 / 13 4) = 0 7 ft (0 2 m)
Channel Velocity =(1 486/0 044)*(0 7^0 667)*(0 005A 5) = 1 8 fps (0 6 m/s)
Channel Effective Manning's Roughness = 0 044
Calculated Shear (Td) = 62 4 * 0 77 * 0 005 = 0 24 psf (11 5 Pa)
Safety Factor = (Tp/Td) _ (4 50 /0 24) = 18 80
tmp#l.txt
Weir Calculator
Given Input Data.
Weir Type ...........
Solving for ....... ... ....
Flowrate ... .. .............
Cv.............. ...
Cd................
Height . .....................
Computed Results.
Depth of Flow . .......
Full Flow .. ... ..............
Velocity ............. .
Crest length .... ...............
Width...... ..................
Area..... .. ..............
Perimeter........ . . .....
Wet Perimeter .. ...........
Wet Area ...........
Percent Full ......
Page 1
Cipolleti
Depth of Flow
11 0300 cfs
0 5500
0.6300
12.0000 in
7 3935 in
22 8071 cfs
1 4729 fps
147.6968 in
144.0000 in
12.2500 ft2
168.7386 in
159.2422 in
7 4884 ft2
61.6128 %
COUNTRY INN SUITES HOTEL
Detention Basin
8/10/1999
Elevation
Onfice
(ft above outlet
(ft"3/s)
300
07278
290
07156
280
07031
270
06904
260
06775
250
06644
240
06509
230
06372
220
06232
210
06089
200
05942
1 90
05792
180
05637
170
05479
160
05315
150
05146
1 40
04972
130
04791
120
04603
110
04407
100
04202
090
03986
080
03758
070
03516
060
03255
050
02971
040
02657
030
02301
020
01879
010
01329
000
00000
Sum outflow 148929
Pond Volume Time to Drain
(ft^3) (seconds)
1081700
1486295
Onface Constant = 0 6
1069613
1494812
11 (0d1
350097
497929
Pipe diameter = 2 e5)
3496 50
506420
(in feet) 0 166667 ( Fee )
349170
515359
348654
524787
Pond top surface area = 10817
348096
534752
(S F )
347492
545305
346835
556506
Pond Bottom surface area = 7191
346118
568426
(S F )
345333
5811 42
344470
594749
343516
609353
342456
625084
341271
642093
339938
660560
338427
680706
336700
702798
334708
727167
332383
754226
329636
784502
326340
818668
322311
857609
317275
902497
310800
954914
302167
1016999
290080
1091557
271950
1181646
241733
1286413
181300
1364447
719100
000
240677 18 Time (seconds)
2 79 ime (Days)
AUG-25-1999 10 15 P 02
lamance activities shall be performed as fol1ows:
. After every significant runoff producing raudall event and at least monthly:
a inspect the wet detention basin system for sediment accumulation, erosion, trash accumulation,
vegetated cover, and general condition.
b. Check and clear the onfice of any obstructions such that drawdown of the temporary pool Occurs
within 2 to 5 days as designed.
2. Repair eroded areas immediately, re -seed as necessary to maintain good vegetative cover, snow vegetative
cover to maintain a maximum height of six inches, and remove trash as needed.
3. inspect and repair the collection system (i_e. catch basins, piping, swales, riprap, etc.) quarterly to
maintain proper functioning.
4. Remove accumulated sediment from the wet detention basin system semi-annually or when depth is
reduced to 75% of the original design depth (see diagram below). Removed sediment shall be disposed
of in an appropriate manner and shall be handled in a manner that will not adversely impact water quality
C. stockpiling near a wet detention basin or stream, etc.).
Tire measuring device used to determine the sediment elevation shall be such that it will give an accurate
depth reading and not readily penetrate into accumulated sediments.
When the permanent pool depth [cads 3.76 feet in the main pond, the sediment "be removed.
When the permanent pool depth reads 3.15 feet in the forebay. the sediment shall be removed.
EL 2L• z
ion'4 obi
FORE RAY
BASIN DIAGRAM
(fill in the blanks)
Permawnt Pool Elevation 3lo eo
Setiimeot Removal Mcvation 32 • z5
Bottom Elevation S 1.06
II 1.:.i err.
25%
5. Remove cattails and other indigenous wetland plants when they cover 50% of the basin surface. These
plants shall be encouraged to grow along the vegetated shelf and forebay berm.
6_ if the basin most be drained for an emergency or to perform maintenance, the flushing of sediment
through the emergency drain shall be minimized to the maximum extent practical
Fc= SWU-102 Rev 399 Page 3 of 4
TOTAL P 02
North Carolina Annual Report
For Business Corporations
Name of 6orpund on CMC CORPORATION
State Of Incorporation
Secretary of $his Corp 10Number 0373663
Federal EmploprldNumber 56-1939296
Flaal Year Ending 12/31/98
Morel vowyear
Check here N information has not changed since most reoaeetly filed Annual Repaet, complete Une 8 only. 0
1 Nephtene agent 8 nphbne otfia mefibrp ad
2 Street eddress and count of registered o16a
3 N registered agent damped, signature of new agent
(wonsture eonstit" consent to NvoYrhranQ
e Enter principal of6oeaddress ham 104 BRITTANY PLACE
goo...
CARY, NC 27511
crry air ap
5 Emar principal office abphone number here
6 Eider name, tie and busleess address of principal officers here FILED
Name GARY S. CHHABRA Two PRES gT
Address 104 BRITTANY PLACE
CARY, NC 27511 8L AV aaNcEr
ARYOf CWA
N NORTH CAROUNA
Name SHAo S . CHHABRA TRIP V ! C E Pac-51 �twT
Address 104 BRITTANY PLACE
CARY, NC 27511
Name SHARAN R. ERHART
Address 113 EAST CAMDEN FOREST WAY
TMI Se )eF rAAy /r
CARY NC 27511
7 11"describe Ills nature ofbustuns BUSINESS SERVICES
6 CertlBcedon of annual report, roast be oanpletad by all corporsdom
(Z S' C�A [,(� v- 313 19
Car . S bC.
mweroee.wr Iryw>veeear
Moll
,2-co-ed
SIATE ,?y
CARS j� RUFUS L. EDMISTEN
STATE OF NORTH CAROLINA 'S i< SECRETARY OF STATE
ANNUAL REPORT ;5 " ANNUAL REPORTS
INCLUDE W 00 FILING FEE I
P O. BOX 29525
'�.
PAYABLE TO N.0 SECRETARY j`r
�'++,„,•;. RALEIGH. NC 27626-0525
OF STATE.
(9191 733-4201
REPORT DUE DATE- 09-29-1995
CORP 10- 0 3 7 3 6 6 3 11 -
FILING NO- A 0 0 1 rr ,� -� F NOTICE DATE- 07-31-1995
DATE OF INC- 07-19-1995
STATE OF INC- NC
1. REGISTERED AGENT & REGISTERED OFFICE MAILING ADDRESS ENTER AGENT NAME A MAILING ADDRESS CHANGE HERE -
CMC CORPORATION
C/O SHAHN S CHHABRA
1003 OUEENSFERRY RD
CARY NC 27511
2.
STREET ADDRESS OF REGISTERED OFFICE ENTER STREET ADDRESS CHANGE HERE -
1003 OUEENSFERRY R0
CARY NC 27511
COUNTY - MAKE
3 IF REGISTERED AGENT CHANGED, SIGNATURE OF NEN AGENT SIGNATURE coNGnrures coN;EMT TO APPotnrnENT
4 ENTER PRINCIPAL OFFICE ADDRESS HERE - CMC CORPORATION
ADDR- 1063 (QUF-f7-7015FE2,ey 2v
CITY- C �q 02- Y ST- NC ZIP- Z7) S 1�
S. ENTER FEDERAL EMPLOYER I0 NUMBER HERE - NUMB- ` / ^ / 9 3 61
6. ENTER NAME, TITLE AND BUSIINNESS ADDRESS OF PRINCIPAL OFFICERS HERE - _
NAME- (finn ��S C i"IHV -(//e /4' ADDR- 1003 GR Ut=�tisr-� .'may
I(— 5-� �T CITY- C l4 %L �/ ST- /✓CZIP-
TITLE- /+ L1 Q /� /
NAME-.SHA44 A) S CHHRB2ri ADDR- I003 G%u(Ezr7U-sF"2y
TITLE- 56-c tl�ETAKy CITY- Cf3 Ky ST-A/C_ ZIP-� ) �/
NAME- AODR-
CITY-
ST-
ZIP-
TITLE-
NAME- ADDR-
CITY-
ST-
ZIP-
TITLE-
7. ENTER NAME AND BUSINESS ADDRESS DIRECTORS HERE -
ATTACH 2ND PAGE IF NECESSARY
pOF
NAME- �S /TDUUc�- ADDR-
-!5-
CITY-
ST-
ZIP-
NAME- ADDR-
CITY-
ST-
ZIP-
NAME- ADOR-
CITY- �C S1.T--y- ZIP-
R
S. BRIEFLY DESCRIBE THE NATURE OF ITS BUSINESS OR ACTIVITIES - e�..Q CSI'�a..L(, MLIN YYjP FLT /�077S JrN L%�a�
CMC CORPORATION
�/�
9. IF NONPROFIT, 10. ;IGNEo- ` .� ` ' ' "�""" DATE- lO y
ARE THERE MEMBERS? IFIRM MUST BE SIGW. 61 OFFICER C CODPORATIONI
YES —NO NAME- C7 S gHH/ 50" -1-7- Su/ZE'JL
- TITLE-
y TWE OR PRIW NAME Alm TITLE
SECRETARY OF STATE ANNUAL REPY RTh the
POST 00 FF ICE 2952ove 1th a 5, RALEIGHH NC 27626-0525
CARS