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HomeMy WebLinkAboutSW8030120_HISTORICAL FILE_20030610STORMWATER DIVISION CODING SHEET POST -CONSTRUCTION PERMITS PERMIT NO. SW8 0'50VL0 DOC TYPE ❑ CURRENT PERMIT ❑ APPROVED PLANS HISTORICAL FILE ❑ COMPLIANCE EVALUATION INSPECTION DOC DATE 2 003 Ow 10 YYYYMMDD O1"O� W /+T F9�G /^\ Michael F. Easley, Governor \ y William G. Ross Jr., Secretary iii North Carolina Department of Environment and Natural Resources O Y Alan W. Klimek, P.E.,Director Division of Water Quality June 10, 2003 Mr. Bert Exum, President WDV, LLC PO Box 1967 Wilmington, NC 28402 Subject: Permit No. SW8 030120 Waterford Way High Density Stormwater Project Brunswick County Dear Mr. Exum: The Wilmington Regional Office received a complete Stormwater Management Permit Application for Waterford Way on April 17, 2003. 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 030120 dated June 10, 2003,'for the construction of Waterford Way. This permit shall be effective from the date of issuance until June 10, 2013, 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, Rick Shiver Water Quality Regional Supervisor RSSarl: S:\WQS\STORMWAT\PERMIT\030120.jun03 cc: Davis Fennell, P.E., Cape Fear Engineering Delaney Aycock, Brunswick County Building Inspections Linda Lewis Wilmington Regional Office Central Files N. C. Division of Water Quality 127 Cardinal Drive Extension (910) 395-3900 Customer service Wilmington Regional Office Wilmington, NC 28405 (910) 350-2004 Fax 1 800 623-7748 nw dw4 NCDENa State Stormwater Management Systems Permit No. SW8 030120 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 Bert Exum, WDV, LLC Waterford Way Brunswick 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 June 10, 2013, and shall be subject to the following specified conditions and limitations: I. DESIGN STANDARDS 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 160,750 square feet of impervious area. 3. The tract will be limited to the amount of built -upon area indicated on page 3 of this permit, and per approved plans. 4. All stormwater collection and treatment systems must be located in either dedicated common areas or recorded easements. The final plats for the project will be recorded showing all such required easements, in accordance with the approved plans. 5. The runoff from all built -upon area within the permitted drainage area of this project must be directed into the permitted stormwater control system. A permit modification must be submitted and approved prior to the construction of additional built -upon area from outside of the approved drainage area. State Stormwater Management Systems Permit No. SW8 030120 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 Bert Exum, WDV, LLC Waterford Way Brunswick 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 June 10, 2013, and shall be subject to the following specified conditions and limitations: I. DESIGN STANDARDS 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 160,750 square feet of impervious area. 3. The tract will be limited to the amount of built -upon area indicated on page 3 of this permit, and per approved plans. 4. All stormwater collection and treatment systems must be located in either dedicated common areas or recorded easements. The final plats for the project will be recorded showing all such required easements, in accordance with the approved plans. 5. The runoff from all built -upon area within the permitted drainage area of this project must be directed into the permitted stormwater control system. A permit modification must be submitted and approved prior to the construction of additional built -upon area from outside of the approved drainage area. 2 State Stormwater Management Systems Permit No. SW8 030120 DIVISION OF WATER QUALITY PROJECT DESIGN DATA SHEET Project Name: Permit Number: Location: Applicant: Mailing Address: Application Date: Receiving Stream/River Basin: Stream Index Number: Classification of Water Body: Drainage Area, acres: Onsite, sq. ft.: Offsite, sq. ft.: Total Impervious Surfaces, sq. ft.: Pond Depth, feet: TSS removal efficiency: Permanent Pool Elevation, FMSL Permitted Surface Area, sq. ft. Permitted Storage Volume, cubic ft.: Temporary Storage Elevation, FMSL Controlling Orifice: Permitted Forebay Volume, cubic ft.: Waterford Way SW8 030120 Brunswick County Mr. Bert Exum WDV, LLC PO Box 1967 Wilmington, NC 28402 April 17, 2003 Jackey's Creek / Cape Fear CPF17 18-77-3 "C Sw" 4.42 4.42 0 160,750 6.00 90% (no filter is required) 22.00 11,137@Permanent Pool 13,356 23.10 1.5" 0 pipe (drawdown in 2-5 days) 6,093 3 State Stormwater Management Systems Permit No. SW8 030120 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. 2. During construction, erosion shall be kept to a minimum and any eroded areas of the system will be repaired immediately. 3. 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. Mowin.9 and revegetation of slopes and the vegetated filter. d. Immediate repair of eroded areas. e. Maintenance of all slopes in accordance with approved plans and specifications. f. Debris removal and unclogging of outlet structure, orifice device, flow spreader, 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 of DWQ. 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. A modification may be required for those deviations. 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. 9. At least 30 days prior to the sale or lease of any portion of the property, the permittee shall notify DWQ and provide the name, mailing address and phone number of the purchaser or leasee. 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 or lease of any portion of the property. Ell State Stormwater Management Systems Permit No. SW8 030120 10. The permittee shall submit to the Director and shall have received approval for revised plans, specifications, and calculations prior to construction, for any modification to the approved plans, including, but not limited to, those listed below: a. Any revision to any item shown on the approved plans, including the stormwater management measures, built -upon area, details, etc. b. Project name change. C. Transfer of ownership. d. Redesign or addition to the approved amount of built -upon area or to the drainage area. e. Further subdivision, acquisition, or sale of all or part of the project area. The project area is defined as all property owned by the permittee, for which Sedimentation and Erosion Control Plan approval or a CAMA Major permit was sought. f. Filling in, altering, or piping of any vegetative conveyance shown on the approved plan. 11. The permittee shall submit final site layout and grading plans for any permitted future areas shown on the approved plans, prior to construction. If the proposed BUA exceeds the amount permitted under this permit, a modification to the permit must be submitted and approved prior to construction. 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. The permittee must maintain compliance with the proposed built -upon area and ensure that the runoff from all the built -upon is directed into the permitted system. 14. 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. 15. The permittee must maintain the current permitted drainage area. No additional runoff from outside of the permitted drainage area boundary may enter the permitted stormwater facilities without first applying for and receiving a permit modification. III. GENERAL CONDITIONS This permit is not transferable except after notice to and approval by the Director. In the event of a change of ownership, or a name change, the permittee must submit a formal permit transfer request to the Division of Water Quality, accompanied by a completed name/ownership change form, 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. The permittee is responsible for compliance with all permit conditions until such time as the Division approves the transfer request. 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. 5 State Stormwater Management Systems Permit No. SW8 030120 3. 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. 4. 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. 5. The permittee grants DENR Staff permission to enter the property during normal business hours for the purpose of inspecting all components of the permitted stormwater management facility. 6. 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. 7. Unless specified elsewhere, permanent seeding requirements for the stormwater control must follow the guidelines established in the North Carolina Erosion and Sediment Control Planning and Design Manual. 8. Approved plans and specifications for this project are incorporated by reference and are enforceable parts of the permit. 9. The permittee shall notify the Division any name, ownership or mailing address changes within 30 days. Permit issued this the 10th day of June, 2003. NORTH CAROLINA ENVIRONMENTAL MANAGEMENT COMMISSION Alan W. Klimek, P.E., Director Division of Water Quality By Authority of the Environmental Management Commission H. a OFFICE USE ONLY Date Received Fcc Paid Permit Number 11 I - a - 0 3 Lt ao �� /S-f 36 / a-d State of North Carolina Department of Environment and Natural Resources Division of Water Quality STORMWATER MANAGEMENT PERMIT APPLICATION FORM This form may be photocopied for use as an original I. GENERAL INFORMATION: 1. Applicant's name (specify the name of the corporation, individual, etc. who owns the project): WDV, LLC 2. Print Owner/Signing Official's name and title (person legally responsible for facility and compliance): Bert Exum, President 3. Mailing Address for person listed in item 2 above: P. O. Box 1967 City: Wilmington State: NC Zip: 28402 Telephone Number: (910) 540-9716 4. Project Name (subdivision, facility, or establishment name - should be consistent with project name on plans, specifications, letters, operation and maintenance agreements, etc.): Waterford Way 5. Location of Project (street address): NC Hwy 17 City: Leland County: Brunswick 6. Directions to project (from nearest major intersection): Located along the north right-of-way on Hwy 17 at the Poole Road intersection 7. Latitude: 34°12'60" Longitude: 78'01'14" of project 8. Contact person who can answer questions about the project: Name: Bert Exum Telephone Number: (910) 540-9716 II. PERMIT INFORMATION: 1. Specify whether project is (check one): X New Renewal Modification Form: SWU-101 Version 3.99 Page 1 of 2. If this application is being submitted as the result of a renewal or modification to an existing permit, list the existing permit number N/A And its issue date (if known) N/A 3. Specify the type of project (check one): Low Density X High Density Redevelor 4. Additional Project Requirements (check applicable blanks): CAMA Major X Sedimentation/Erosion Control General Permit Other 404/401 Permit NPDES Stormwater Information on required state permits can be obtained by contacting the Customer Service Center at 1-977-623-6748. 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. Stormwater will be treated in a wet detention basin. 2. Stormwater runoff from this project drains to the Fear 3. Total Project Area: 5.06 acres 4. Project Built Upon Area: 5. How many drainage basins does the project have? 1 River basin. 83.5 % 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. Basin Information Drainage Areal Drainage Area 2 Receiving Stream Name Jackeys Creek Receiving Stream Class C Sw Drainage Area 192,540 sf (4.42 ac.) Existing Impervious* Area N/A Proposed Impervious* Area 160,750 sf (3.69 ac.) Impervious* Area (total) 83.5 % Impervious*.Surface Area Drainage Area,, Drainage Area 2 On -site Buildings 28,310 sf (0.65 ac.) On -site Streets N/A On -site Parking 126,340 sf (2.90 ac.) On -site Sidewalks 6,100 sf (0.14 ac.) Other on -site N/A Off site N/A Total: 160,750 sf (3.69 ac.) Total: ' hnpervtous area is defined as the built upon area including, but not limited to, buildings, roads, parking areas, sidewalks, gravel areas, etc. Forth: SWU-101 Version 3.99 Page 2 of L, 7. How was the off -site impervious area listed above derived? N/A 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 covenants are intended to ensure ongoing compliance with state stornnvater management permit number as issued by the Division of Water Quality These covenants may not be changed or deleted without the consent of the State. 2. No more than ** square feet of any lot shall be covered by structures or impervious materials. Impervious materials include asphalt, gravel, concrete, brick, 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 area of the permitted amount requires a state stormwater management permit modification prior to construction. 5. Al/permitted runofffrom outparcels or future development shall be directed into the permitted stormwater control system. These connections to the stormwater control systems 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 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 Permits Unit at (919) 733-5083 for the status and availability of these forms. Form SWU-102 Wet Detention Basin Supplement Form SWU-103 Infiltration Basin Supplement Form SWU-104 Low Density Supplement Form SWU-105 Curb Outlet System Supplement Form SWU-106 Off -Site System Supplement Form SWU-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 V1. 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. Please indicate that you have provided the following required information by initialing in the space provided next to each item. • Original and one copy of the Stormwater Management Permit Application Form • One copy of the applicable Supplement Form(s) for each BMP • Permit application processing fee of $420 (payable to NCDENR) • Detailed narrative description of stormwater treatment /management • Two copies of plans and specifications, including: -Development/Project name -Engineer and firm -Legend -North Arrow -Scale -Revision number & date -Mean high water line -Dimensioned property / project boundary -Location map with named streets or NCSR numbers Initials lzcS'a RG4LC Rer cf -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 submittal authority to another individual or firm so that they may provide information on yo behalf, please complete this section: Designated agent (individual or firm): Cape Fear Engineering, Inc. Mailing Address: 151 Poole Road, Suite 100 City: Belville State: NC Phone: (910) 383-1044 Fax: (910)383-1045 VIII. APPLICANT'S CERTIFICATION Zip: 28451 I, (print or type name ofperson listed in General Information, item 1) Bert Exum 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: Date: 1 �3 Fonn: SWU-101 Version 3.99 Page 4 of 4 r_"' _­ "' ­ ____ Permit No. WQ00213-2 June 11.2003 L•fJvC:CER'S CFRTIRCAT• ION ?W ✓ Partial Final 1, &6 jNIfCLL; as a duly registered Professional Engineer in the State of North Carolina, having been authorized to observe (periodically. weekly, full time) the construction of the project, Leii.ANDe SwAs, Co • for the Proiect Name rlLocation and Cowui- Permittee hereby state that, to the best of my abilities, due care and diligence was used in the observation of the construction such that the construction was observed to be built within substantial compliance of this permit; 15A NCAC 2H .0200; the Division of Water Quality's (Division) Gravity Sewer Minimum Design Criteria adopted February 12, 1996 as applicable; the Division's Minimum Design Criteria for the Fast -Track Permitting of Pump Stations and Force Mains adopted June 1, 2000 as applicable: and other supporting materials. North Carolina Professional Engineer's seal, signature, and date; Z 3bao3 SEAL 024908 "W ODD WtJD DO- (8DAVI� SrA 1000 - 131C)—S.52 6AR1DSJ 6W80AY UOADC) STA 10 It 00 Z 3166 SrA 36100 — -5745-0 The above Engineer's Certification shall be completed and submitted to the address below with one copy of the "Construction Record Drawings" of the wastewater collection system extension as well as supporting design calculations for any pump stations permitted as part of this project. This project shall not be considered complete nor allowed to operate until this Engineers Certification and all required supporting documentation have been received by the Division. Any wastewater now made tributary to the wastewater collection system extension prior to completion of this Engineer's Certification shall be considered a violation of the permit and shall subject the Permiaee to appropriate enforcement actions. NOR1 H CAROLINA DIVISION OFWATER QUALITY WATER QUALITY SECTION NON -DISCHARGE PERI4,MITTING UNIT 1617 MAIL SERVICE CENTER P,' LEIGIII, NORTi0ROrN27fi99-517iAA1 4 CAPE FEAR Engineering, Inc. April 17, 2003 Linda Lewis NCDENR Water Quality 127 Cardinal Dr. Ext. Wilmington, NC 28405 RE: Waterford Way (SW8 030120) Dear Ms. Lewis: RECEIVED APR 17 2003 BY:_ c Please find the enclosed response to your request for additional information for the above referenced project: 1. Wetland species table has been added to the detail sheet. 2. The application page has been revised to show a project area of 5.06 acres. 3. The built upon areas in the application are shown in square feet. 4. Sidewalk widths have been added to the plan. 5. Permanent pool dimensions have been revised to include the radii. 6. The SA/DA ratio has been revised to 4.78. The calcs and first page of the Wet Detention Basin Supplement have been revised and included. 7. Detail sheet has been revised to show a 1.5" orifice. I trust this information to be sufficient for your review and approval. If you have any questions or require additional information, please contact this office. Thank you Jeffrey Petroff, E.I. 151 Poole Road, Suite 100 • 5elville, NC 2B451 • TEL: (910) 353-1044 • FAX: (910) 353-1045 www.capefeareng.com RECEIVED WET POND DATA SHEET Waterford Way - 5 ac. Commercial Site APR 17 2003 POND # I DWQ PROJ# SW3031Z0 DRAINAGE AREA (Ad) _ IMPERVIOUS AREA (Ai): BUILDINGS ROAD5 PARKING SIDEWALKS 4.42 ACRES O.G5 ACRE5 0.00 ACRE5 2.90 ACRES 0. 14 ACRES TOTAL: 3.G9 ACRES PERCENT IMPERVIOUS (1): 17ATIZLO3 SEAL 024908 _ �f-'k:NG I NE'v I = Ad/Ai = 53.48% -c— POND# I SHALL BE G. DEEP AND DESIGNED TO REMOVE 90% T55. 5A/DA= 4.76 REQUIRED SURFACE AREA AT PERMANENT POOL: 5AREQ.= 0.21 127G AC. = 5203.15 51' SURFACE AREA PROVIDED AT PERMANENT POOL (EL. 22.0)= 1 1 137 5F .......................................................................................................................... 5A PROV'D= 1 1 137 > 9203. 18 =5A REQ'D OK .........................................................................................................................: MINIMUM REQUIRED VOLUME (SIMPLE METHOD BY TOM 5CHUELER) Rv=0.05+0.009'(I) Rv= 0.501357 VOLUME= I "'RV'Ad = 0.295 1 7 AC -FT = 12657.5 FT ^ 3 VOLUME PROVIDED AT TEMPORARY POOL: INCREM. 5A (5F) VOL. (CF) 22 11137 0 23 12645 1 199 1 24 14459 13G52 5ET TEMP. POOL ELEVATION: REQ'D EL.= U5E EL. _ VOL. PROV'D = 23.OG347 f- 23. 1 1335G.2 CF TOTAL VOL. (CF) 0 11991 25G43 .......................................................................................................................... VOL. PROV'D= 1335G.2 > 12857.5 =VOL. REQ'D OK .........................................................................................................................: FOREBAY 5121NG: PERMANENT POOL VOLUME: INCREM. TOTAL €I- 5A (5P) VOL. (CF) VOL (CF) IG 2031 0 0 17 2834 2432.5 2432.5 18 3G95 32G4.5 5G97 19 4G 12 4153.5 9850.5 20 558G 5039 14949.5 21 GGIG GIOI 21050.5 22 884G 7731 28751.5 REQ'D VOLUME = 20% Of TOTAL PERMANENT DA51N VOLUME = 575G.3 CP CHECK POREBAY VOLUME INCREM. TOTAL EL. 5A F VOL (CP) VOL. (CF) 18 71G 0 0 19 1070 893 893 20 1481 1275.5 2 1 G8.5 21 1948 1714.5 3883 22 2472 2210 G093 PROV'D VOLUME = .......................................................................................................................... G093 CP VOL. PROV'D= .........................................................................................................................: 6093 > 575G =VOL. REQ'D OK ORIFICE SIZING: REQ'D DRAWDOWN TIME = 2-5 DAYS 02= 0.074407 CFS (FOR 2 DAY DRAWDOWN) Q5= 0.0297G3 CPS (FOR 5 DAY DRAWDOWN) SELECT A 1.5 INCH CIRCULAR ORIFICE, (PERM. POOL EL. = 22 ) Q PROV'D= Cd'A'(2gh)^ 1/2 WHERE: Cd= O.G A= 0.01227 51' g= 32.2 FPS/5 h= avg head: = 0.51875 Q PROV'D= 0.042555 .................................................................... Q2> 0,042556 >Q5 OK :...................................................................: DRAWDOWN TIME: TIME = VOLUME = 3.49G7 DAYS Q PKOV'D o�QF W A rF9QG Michael F. Easley, Governor y William G. Ross Jr., Secretary DW North Carolina Department of Environment and Natural Resources 1 Alan W. Klimek, P.E. Director Division of Water Quality April 2, 2003 Mr. Bert Exum, President WDV, LLC PO Box 1967 Wilmington, NC 28402 Subject: REQUEST FOR ADDITIONAL INFORMATION Stormwater Project No. SW8 030120 Waterford Way Brunswick County Dear Mr. Exum: The Wilmington Regional Office received a Stormwater Management Permit Application for Waterford Way on January 24, 2003.- A preliminary review of that information has determined that the application is not complete. The following information is needed to continue the stormwater review: 1. Please specify by name the wetland species to be planted on the 6:1 shelf. 2. Note #6 on the Site and Utilities plan indicates that the project area is 5.06 acres, but the application reports only 4.42 acres. Please clarify. 3. Please report all built -upon areas in square feet on the application. 4. Please provide the sidewalk widths on the site plan. 5. Please add the radii to the permanent pool contour dimensions. 6. The SA/DA ratio for a 6.0' deep pond at 83.5% impervious is 4.81, not 4.32. Please recalculate and provide the correct amount of surface area at the permanent pool contour, taking comment 42 into account. 7. A 21 orifice is specified on Sheet 4, but the calculations and supplement show a 1.5"0. Please correct and revise as needed. ♦I N. C. Division of Water Quality 127 Cardinal Drive Extension (910) 395-3900 Customer service Wilmington Regional office Wilmington, NC 28405 (910) 350-2004 Fax 1 800 623-7748 NCtJEhet Mr. Exum April 2, 2003 Stormwater Application No. SW8 030120 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 May 2, 2003, 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, e6�c&u4" Linda Lewis Environmental Engineer RSS/arl: S:\WQS\STORMWAT\ADDINFO\2003\030120.APR03 cc: Linda Lewis Davis Fennell, P.E. FORM CAPE FEAR j Engineering, Inc. 151 Poole Road, Sode 100 BeWle, NC 28451 TEL (910)383-1044 FAX (910)383-1045 www.capefeareng.com To: NCDENR — Div. of Water Quality 127 Cardinal Drive Ext. Wilmington, NC 28405 Attn: Linda Lewis ❑ As Requested ❑ For Your Files ❑ Sent via Mail ❑ Sent via Courier Transmittal High Density -SW Applic Waterford Way 5 Acre Commercial Site ❑ For Distribution ® For your Review / Action / Approval Quantity Drawing No. Description 2 Sets Plans 2 Copies Design Narrative with Supporting Calcs. 2 Original and One Copy of Application 2 Original and One Copy of Wet Detention Basin Supplement 1 $420.00 Application Fee REMARKS Attached please find the above described materials for your review and approval. Should you have any questions, comments, or require additional information regarding this matter, please contact this office. CC: Cape Engineering, Inc. File Signed 0 K. Davis Fennell, PE Trans-NCDENR-20jan03.doc Permit No. '_54-1.00 J o120 (to be provided by DWQ) State of North Carolina Department of Environment and Natural Resources Division of Water Quality STORMWATER MANAGEMENT PERMIT APPLICATION FORM WET DETENTION BASIN SUPPLEMENT This form may be photocopied for use as an original DWQ Stormwater Management Plan Review: A complete stormwater management plan submittal includes an application form, a wet detention basin supplement for each basin, design calculations, and plans and specifications showing all basin and outlet structure details. I. PROJECT INFORMATION Project Name: Waterford Way Contact Person: Bert Exum Phone Number: (910) 540-9716 For project with multiple basins, specify which basin this worksheet applies to: N/A elevations Basin Bottom Elevation 16.0 ft. (floor of the basin) Permanent Pool Elevation 22.0 ft. (elevation of the orifice) Temporary Pool Elevation 23.2 ft. (elevation of the discharge structure overflow) areas Permanent Pool Surface Area 11137 sq. ft. (water surface area at the orifice elevation) Drainage Area 4.42 ac. (on -site and off -site drainage to the basin) Impervious Area 3.69 ac. (on -site and off -site drainage to the basin) volumes Permanent Pool Volume 28,781.5 cu. ft. (combined volume of main basin and forebay) Temporary Pool Volume 10,845.5 cu. ft. (volume detained above the permanent pool) Forebay Volume 6,093 cu. ft. (approximately 20% of total volume) Other parameters SA/DA' 4.78 (surface area to drainage area ratio from DWQ table) Diameter of Orifice 1.5 in. (2 to 5 day temporary pool draw -down required) Design Rainfall 1 in. Design TSS Removal 2 90 % (minimum 85% required) Form: SWU-102 Rev3.99 Page 1of4 Footn6tes: When using the Division SA/DA tables, the correct SA/DA ratio for permanent pool sizing should be computed based upon the actual impervious % and permanent pool depth. Linear interpolation should be employed to determine the correct value for non- standard table entries. z In the 20 coastal counties, the requirement for a vegetative filter may be waived if the wet detention basin is designed to provide 90% TSS removal. The NCDENR BMP manual provides design tables for both 85% TSS removal and 90% TSS removal. II. REQUIRED ITEMS CHECKLIST The following checklist outlines design requirements per the Stotmwater Best Management Practices Manual (N.C. Department of Environment, Health and Natural Resources, February 1999) and Administrative Code Section: 15 A NCAC 2H .1008. Initial in the space provided to indicate the following design requirements have been met and supporting documentation is attached. If the applicant has designated an agent in the Stormwater Management Permit Application Form, the agent may initial below. If a requirement has not been met, attach justification. Applicants Initials: (ZLL C a. The permanent pool depth is between 3 and 6 feet (required minimum of 3 feet). Q «d b. The forebay volume is approximately equal to 20% of the basin volume. jitcz c. The temporary pool controls runoff from the design storm event. /1 c4Z d. The temporary pool draws down in 2 to 5 days. /2csgr e. If required, a 30-foot vegetative filter is provided at the outlet ( include non -erosive flow calculations) /2cct f. The basin length to width ratio is greater than 3:1. (2tt,t g. The basin side slopes above the permanent pool are no steeper than 3:1. 1ZLLt It. A submerged and vegetated perimeter shelf with a slope of 6:1 or less (show detail). Auc i. Vegetative cover above the permanent pool elevation is specified. 2cd.6 j. A trash rack or similar device is provided for both the overflow and orifice. 11"L k. A recorded drainage easement is provided for each basin including access to nearest right - of —way. A cc.r I. If the basin is used for sediment and erosion control during construction, clean out of the basin is specified prior to use as a wet detention basin. �t 6 m 4A mechanism is specified which will drain the basin for maintenance or an emergency. Y par4&-bit Pd wip I1I. WET DETENTION BASIN OPERATION AND MAINTENANCE AGREEMENT The wet detention basin system is defined as the wet detention basin, pretreatment including forebays and the vegetated filter if one is provided. Form: SWU-102 Rev 3.99 Page 2 of 4 . This system (check one) 0 doeAdoesot 'ncorporate a vegetated filter at the outlet. This system (check one) 0 doeot orporate pretreatment other than a forebay. Maintenance activities shall be performed as follows: After every significant runoff producing rainfall 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 orifice 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, mow 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 (i.e. stockpiling near a wet detention basin or stream, etc.) The measuring device used to determine the sediment elevation shall be as such that it will give an accurate depth reading and not readily penetrate into accumulated sediments. When the permanent pool depth reads 5.25 feet in the main pond, the sediment shall be removed. When the permanent pool depth reads 3 feet in the forebay, the sediment shall be removed. Sediment Remov I EL= 19.0 75% _________________ Bottom Elevation 1$.0 25% FOREBAY BASIN DIAGRAM (fill to the blanks) Permanent Pool Elevation = 22.0 Sediment Removal Elevation =17.50 75% ------------------------------------ Bottom Elevation = 16.0 25% MAIN POND 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. Form: SWU-102 Rev 3.99 Page 3 of 4 6. If the basin must 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. 7. All components of the wet detention basin system shall be maintained in good working order. I acknowledge and agree by my signature below that I am responsible for the performance of the seven maintenance procedures listed above. I agree to notify DWQ of any problems with the system or prior to any changes to the system or responsible party. Print name: Bert Exum Title: President Address: P. O. Box 1967 Wilmington, NC 28402 Phone: (910) 540-9716 Signature: Date: L z boo's Note: The legally responsible party should not be a homeowners association unless more than 50% of the lots have been sold and a resident of the subdivision has been named the president. I, Anthony E. Mills a Notary Public for the State of North Carolina County of Brunswick do hereby certify t at Bert Exum personally appeared before me this 7dr day of �„ U�2 Zpp�j and acknowledge the due execution of the foregoing wet detention basin maintenance requir6rients. Witness my hand and official seal, My commission expires November 29' 2004 Form: SWU-102 Rev 3.99 Page 4 of 4