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HomeMy WebLinkAboutSW8070605_Current Permit_20070621 F W ATF O p Michael F.Easley,Governor William G.Ross Jr.,Secretary -5 II Itr- North Carolina Department of Environment and Natural Resources p " rd a1"n.e„ Coleen H.Sullins,Director Division of Water Quality ma 04 June 21, 2007 Cumbee Rd. Partners, LLC Attn.:Adam Lisk, Member-Manager 7616 Hawk Road Wilmington, NC 28411 Subject Permit No. SW8070605 Sea Wynde Plantation, Phase I High Density Stormwater Project Brunswick County Dear Mr. Lisk: The Washington Regional Office received a completed Stormwater Application for the subject project on June 7, 2007. 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. SW8070605 dated June 21, 2007 to Cumbee Road Partners, LLC for five wet detention ponds to serve the Sea Wynde Plantation, Phase I development located at the intersection of Cumbee Road and NC 17 near Shallotte, NC. This permit shall be effective from the date of issuance until June 21, 2017 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. The issuance of this permit does not resolve any previous violations of the stormwater rules for construction without a permit 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, 6714 Mail Service Center, Raleigh, NC 27699-6714. 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 Samir Dumpor or me at(252)946-6481. 'ncer Iy, L Al Ho ge, egiona upery or Surface Water Protection Section Washington Regional Office AH/sd: J:IWPDATA\WQSl State SW SD1Permits—Wet Pond cc: John F.Oglesby, PE,Trigon Engineering(700 Blue Ridge Rd.St. 101, Raleigh, NC 27606) Brunswick County Building Inspections Department Washington Regional Office Wilmington Regional Office Central Files North Carolina Division of Water Quality Internet: www.ncwatergualitv.orn One 943 Washington Square Mall Phone(252)946-6481 NAthCarolina Washington,NC 27889 Fax (252)946-9215 lltul'Rlt�l,' An Equal Opportunity/Affirmative Action Employer—50%Recycled/10%Post Consumer Paper ` " State Stormwater Management Systems Permit No. SW8070805 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 Cumbee Road Partners,LLC Sea Wynde Plantation, Phase I FOR THE construction, operation and maintenance of stormwater management systems 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 for five wet detention ponds to serve the Sea Wynde Plantation, Phase I development located at the intersection of Cumbee Road and NC 17 near Shallotte, NC. This permit shall be effective from the date of Issuance until June 21, 2017 and shall be subject to the following specified conditions and limitations: 1. 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 pages 3 and 4 of this permit,the Project Data Sheet 3. A maximum of 52.21 acres of built upon area is allowed on this 93.43 acre site. 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 approved plans. 5. Approved plans and specifications for this project are incorporated by reference and are enforceable parts of the permit 6. Plan revisions for the 14.75 acres of impervious area for the Future Commercial development shall be submitted to the Division and approved prior to the construction of those impervious areas. DIVISION OF WATER QUALITY WET PONDS-PROJECT DATA Project Name: Sea Wynde Plantation, Phase I Permit Number. SW8070605 Location: Brunswick County Applicant Cumbee Rd. Partners, LLC Mailing Address: 7616 Hawk Road Wilmington, NC 28411 Application Date: 06/07/2007 Receiving Stream: Williams Branch Classification of Water Body: C;SW Total Site Area: 93.43 ac Pond#1 Pond#2 Pond#3 Drainage area: 57.17 ac 15.78 ac 5.77 ac Total Impervious allowed on site: 33.25 ac. 9.33 ac 2.83 ac Residential: 18.50 ac. Commercial: 14.75 ac. Wet Pond Depth: 6.0 ft 6.0 ac 4.0 ac Required Storage Volume: 118,706 cf 33,280 cf 10,284 cf Provided Storage Volume: 124,678 of 35,964 cf 10,894 cf Required Surface Area: 63,503 sf 22,683 sf 10,606 sf Provided Surface Area: 67,907 sf 24,473 sf 11,158 sf Controlling Orifice: (2)3"@ el. 32.0 ft 2"@ el. 35.0 ft 2.5"@ el.43.5 ft Pond#4 Pond#5 Drainage area: 12.12 ac 2.59 ac Total Impervious allowed on site: 5.12 ac. 1.68 ac Wet Pond Depth: 6.0 ft 3.0 ac Required Storage Volume: 18,918 cf 5,970 cf Provided Storage Volume: 20,728 cf 6,280 cf Required Surface Area: 11,720 sf 8,518 sf Provided Surface Area: 12,177 sf 10,229 sf Controlling Orifice: 2.5"@ el.43.5 ft (2)2"©el.48.0 ft 6. No homeowner/lot owner/developer shall be allowed to fill in, alter, or pipe any vegetative practices (such as males) shown on the approved plans as part of the stormwater management system without submitting a revision to the permit and receiving approval from the Division. 7. 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 of the project area. In addition, the Director may determine that other revisions to the project should require a modification to the permit. —8. The Director may-notify the permittee-when-the--permitted site does not ire rniriiirrum--` 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. II. SCHEDULE OF COMPLIANCE 1. The permittee will comply with the following schedule for construction and maintenance of the stormwater management system. a. The stormwater management system shall be constructed in its entirety, vegetated and operational for its intended use prior to the construction of any built-upon surfaces except roads. b. During construction, erosion shall be kept to a minimum and any eroded areas of the system will be repaired immediately. 2. The facilities must be properly maintained and operated at all times. The approved Operation and Maintenance Plan must be followed in its entirety and maintenance must occur at the scheduled intervals. 3. The permittee shall at all times provide the operation and maintenance necessary to assure the permitted stormwater system functions at optimum efficiency 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. 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. 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. 6. Upon completion of construction 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. Mail the Certification to the Washington Regional Office, 943 Washington Square Mall, Washington, North Carolina, 27889, attention Division of Water Quality. 7. A copy of the approved plans and specifications shall be maintained on file by the Permittee for a minimum of five years from the date of the completion of construction. III. GENERAL CONDITIONS 1. 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- 215.6(a)to 143-215.6(c). 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 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. 6. The Permittee, at least six(6) months prior to the expiration of this permit, shall submit in writing a request for an extension along with appropriate application fee. Cumbee Road Partners, LLC-Sea Wynde Plantation, Phase I Stormwater Permit No. SW8070605 Designer's Certification I, , asaduly Registered Professional Engineer in the State of North Carolina, having been authorized to, observe (periodically/weekly/full time) the construction of the project, (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. Signature Registration Number Date 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. All roof drains are located such that the runoff is directed into the system. 5. The outlet/bypass structure elevations are per the approved plan. 6. The outlet structure is located per the approved plans. 7. Trash rack is provided on the outlet/bypass structure. 8. All slopes are grassed with permanent vegetation. 9. Vegetated slopes are no steeper than 3:1. 10. The inlets are located per the approved plans and do not cause short-circuiting of the system. 11. The permitted amounts of surface area and/or volume have been provided. 12. Required drawdown devices are correctly sized per the approved plans. 13. All required design depths are provided. 14. All required parts of the system are provided, such as a vegetated shelf, and a forebay. 15. The required system dimensions are provided per the approved plans. Permit issued this the twenty-first day of June, 2007. NORT CAROLINA ENVIRONMENTAL MANAGEMENT COMMISSION )(_. z__ \___ -r...___,— fior Coleen H. Sullins, Director Division of Water Quality By Authority of the Environmental Management Commission Permit Number SW8070605 • , } • 1 OFFICE USE ONLY - Date Received Fee Paid Permit Number If- ()L'l © 4071600 .51/Qga/76rnr�s' State of North Carolina SVI/ 6%/6 7 RECEIVED Department of Environment and Natural Resources Division of Water Quality JUNN U / 200STORMWATER MANAGEMENT PERMIT APPLICATION FORM This form may be photocopied for use as an original DWQ-WARO I. GENERAL INFORMATION 1. Applicants name (specify the name of the corporation,individual,etc.who owns the project): Cumbee Rd. Partners, LLC 2. Print Owner/Signing Official's name and title (person legally responsible for facility and compliance): Adam Lisk, Member-Manager 3. Mailing Address for person listed in item 2 above: 7616 Hawk Road City:Wilmington State: NC Zip: 28411 Telephone Number: ( 910 ) 352-0634 4. Project Name (subdivision,facility,or establishment name-should be consistent with project name on plans, specifications,letters,operation and maintenance agreements,etc.): Sea Wynde Plantation Phase 1 5. Location of Project(street address): Intersection of NC17(Ocean Hwy.West)and Cumbee Road (S.R. 1131) City: Shallotte County: Brunswick 6. Directions to project(from nearest major intersection): at the intersection of Cumbee Road and NC17 7. Latitude: 33°59'46"N Longitude: 78° 19'21"W of project 8. Contact person who can answer questions about the project: Name: S. Chester Holder, P.E. Telephone Number: ( 336 ) 668-0093 II. PERMIT INFORMATION: 1. Specify whether project is (check one): X New Renewal Modification Form SWU-101 Version 3.99 Page 1 of 4 2. If this application is being submitted as the result of a renewal or modification to an existing permit,list the existing permit number and its issue date(if known) 3. Specify the type of project (check one): Low Density X High Density Redevelop General Permit Other 4. Additional Project Requirements (check applicable blanks): CAMA Major X Sedimentation/Erosion Control X 404/401 Permit NPDES Stormwater Information on required state permits can be obtained by contacting the Customer Service Center at 1-877-623-6748. IlT. 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. All Storm Water Shall be collected in the storm drainage system and discharged into wet detention ponds 2. Stormwater runoff from this project drains to the lumber River basin. 3. Total Project Area: 93.43 acres 4. Project Built Upon Area: 55.9 % 5. How many drainage areas does the project have? 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 Area 1 Drainage Area 2 Receiving Stream Name Williams Branch Williams Branch Receiving Stream Class CSW CSW _ Drainage Area 57.17 AC 15.78 AC Existing Impervious*Area 0 AC 0 AC Proposed Impervious*Area 33.25 AC 9.33 AC %Impervious*Area(total) /58.2 % 59.1% Impervious*Surface Area Drainage Area 1 Drainage Area 2 On-site Buildings 22.36 AC 5.12 AC On-site Streets 6.36 AC 3.63 AC On-site Parking 4.53 AC 0.58 AC On-site Sidewalks _ Other on-site Off-site Total: 33.25 AC Total: 3AC 1.33 A c J Fc' *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 ***For additional drainage areas please see attachment 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 stormwater 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 3250 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 of 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 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 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 initialing in the space provided next to each item. Initials • Original and one copy of the Stormwater Management Permit Application Form J FO • One copy of the applicable Supplement Form(s) for each BMP ,1 F • Permit application processing fee of$420 (payable to NCDENR) ,S f • Detailed narrative description of stormwater treatment/management J FO • Two copies of plans and specifications,including: J F O Development/Project name Engineer and firm Legend ✓-North arrow • Scale v Revision number&date v 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 L.-e Wetlands delineated,or a note on plans that none exist v Existing drainage (including off-site),drainage easements,pipe sizes,runoff calculations Drainage areas delineated t/Vegetated buffers (where required) VII. AGENT AUTHORIZATION If you wish to designate authority to another individual or firm so that they may provide information on your behalf,please complete this section. Designated agent(individual or firm): JO!-i tii • 0c,(,(✓S 3 y, jE T RI Gjnt enc Mailing Address: 700 ,i U r, �d�e P d .j- I O I City: 2 k ; 3 M C. State: Zip: 2.7 6 Phone: ( / ) 753- So/ I Fax: ( 9 ) 7 J - 5 6 fel VIII. APPLICANT'S CERTIFICATION I, (print or type name of person listed in General Information,item 2) Adam Lisk 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:C:(� Form SWU-101 Version 3.99 Page 4 of 4 2: If this application is being submitted as the result of a renewal or modification to an existing permit, list the existing permit number and its issue date(if known) 3. Specify the type of project(check one): Low Density High Density Redevelop General Permit Other 4. Additional Project Requirements (check applicable blanks): CAMA Major Sedimentation/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. 2. Stormwater runoff from this project drains to the River basin. 3. Total Project Area: acres 4. Project Built Upon Area: 5. How many drainage areas does the project have? 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 Area 3 Drainage Area 4 Receiving Stream Name Williams BR Williams BR Receiving Stream Class CSW CSW Drainage Area 5.77 AC 12.12 AC Existing Impervious*Area 0 0 Proposed Impervious*Area 2.83 AC 5.12 AC %Impervious*Area(total) 49.05 % 42.2 % Impervious* Surface Area Drainage Area 3 Drainage Area 4 On-site Buildings 1.86 AC 3.30 AC On-site Streets 0.97 AC 1.82 AC On-site Parking _ On-site Sidewalks - Other on-site _ Ott-site - ITotal: 2.83 AC Total: 5.12 AC *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 .2.1f this application is being submitted as the result of a renewal or modification to an existing permit,list the existing permit number and its issue date(if known) 3. Specify the type of project(check one): Low Density High Density Redevelop General Permit Other 4.Additional Project Requirements (check applicable blanks): CAMA Major Sedimentation/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. 2. Stormwater runoff from this project drains to the River basin. 3. Total Project Area: acres 4. Project Built Upon Area: 5. How many drainage areas does the project have? 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 Area 5 Receiving Stream Name Williams BR Receiving Stream Class CSW Drainage Area 2.59 AC Existing Impervious*Area 0 Proposed Impervious*Area 1.68 AC %Impervious*Area(total) 64.9% Impervious* Surface Area Drainage Area 5 On-site Buildings 0.83 AC On-site Streets 0.85 AC On-site Parking _ On-site Sidewalks _ Other on-site _ Off-site Total: 1.68 AC 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 Permit No. (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: CLAmoce .- e4 Use_ -D�vckopnneA (5 ea- (4261A e 'Pt cyroA:or PVlate I Contact Person: inr- F- ! l es o1, E. Phone Number: (q 19 ) 155— 5 01 J For projects with multiple basins, specify which basin this worksheet applies to: IAkk Pon a 4 elevations Basin Bottom Elevation g6.0 ft. (floor of the basin) Permanent Pool Elevation 3a. 0 ft. (elevation of the orifice) Temporary Pool Elevation 33 15 ft. (elevation of the discharge structure overflow) areas Permanent Pool Surface Area loll 9 07 sq. ft. (water surface area at the orifice elevation) Drainage Area 51. I-1 ac. (on-site and off-site drainage to the basin) Impervious Area 33.05 ac. (on-site and off-site drainage to the basin) volumes Permanent Pool Volume 91(o, 'B3`7 cu. ft. (combined volume of main basin andforebay) Temporary Pool Volume 1)4, (o1S cu. ft. (volume detained above the permanent pool) Forebay Volume 54, 9 a cu. ft. (approximately 20%of total volume) Other parameters SA/DA1 Q. 55 % (surface area to drainage area ratio from DWQ table) Diameter of Orifice 2 ig4.3 in. (2 to 5 day temporary pool draw-down required) Design Rainfall I. 0 in. Design TSS Removal 2 'S5. % (minimum 85%required) Form SWU-102 Rev 3.99 Page 1 of 4 - Footnotes: 1 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. 2 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 Stormwater 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 Li a. The permanent pool depth is between 3 and 6 feet(required minimum of 3 feet). I •(I b. The forebay volume is approximately equal to 20%of the basin volume. ,�tS c. The temporary pool controls runoff from the design storm event. AAA d. The temporary pool draws down in 2 to 5 days. 410 e. If required, a 30-foot vegetative filter is provided at the outlet(include non-erosive flow calculations) i f. The basin length to width ratio is greater than 3:1. « g. The basin side slopes above the permanent pool are no steeper than 3:1. -� h. A submerged and vegetated perimeter shelf with a slope of 6:1 or less(show detail). i 1 i. Vegetative cover above the permanent pool elevation is specified. 't A j. A trash rack or similar device is provided for both the overflow and orifice. M k. A recorded drainage easement is provided for each basin including access to nearest right- of-way. See NI A 1. 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. /14 m. A mechanism is specified which will drain the basin for maintenance or an emergency. III. 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. This system(check one) 0 does 0 does not incorporate a vegetated filter at the outlet. This system(check one) 0 does 0 does not incorporate pretreatment other than a forebay. Form SWU-102 Rev 3.99 Page 2 of 4 Maintenance activities shall be performed as follows: 1. 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 such that it will give an accurate depth reading and not readily penetrate into accumulated sediments. When the permanent pool depth reads 4.5 feet in the main pond,the sediment shall be removed. When the permanent pool depth reads 4.Jr feet in the forebay,the sediment shall be removed. BASIN DIAGRAM (fill in the blanks) v Permanent Pool Elevation 3a.0 Sediment Re oval El. al.S :75 0 _ Sediment Removal Elevation )1.'J i 75% Bottom Ele ation D b.Q t % Bottom Elevation Q 6.Q 25% FOREBAY 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. 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. Form SWU-102 Rev 3.99 Page 3 of 4 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:Adam Lisk Title: Manager-Member Cumbee Road LLC Address: 7616 Hawk Road,Wilmington, North Carolina 28411 Phone: 910-352-0634 Signature: Date: ' (� —7 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, La4 iv `J IbtL , a Notary Public for the State of N ' T Card I re County of l-}-F , do Ijereby certify that I lYL L5(. personally appeared before me this LOLL day of 'vat , 1, and acknowledge the due execution of the forgoing wet detention basin maintenance requirements. Witness my hand and official seal, `` S.„„, 111110�� '� y P 11/,4 t, . PUBt Ate••., •;'�V ,,Co N,cy a``�� SEAL My commission expires ailfIChqf A ct'g Form SWU-102 Rev 3.99 Page 4 of 4 WET DETENTION BASIN SUPPLEMENT ADDENDUM Wet Pond#1 SECTION I: PROJECT INFORMATION Other parameters Design TSS Removal: 85% Requirements for vegetative filter have been met: Pond will be constructed with a 250' grassed swale located downstream of pond outlet. SECTION II: REQUIRED ITEMS CHECKLIST Replace item "k"with the following: k. Drainage easements are not required to maintain pond. Pond is accessible from the public right of way and has room for maintenance equipment on all sides with out encroachment on adjacent property. On plat, pond area will be included in the adjacent open area. • Permit No. (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 Stonnwater 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: C L►r‘b te, (Z o a.a etrY a U 5 e rD tv e l o f rn.e..+r:\ (Se L kin e'P l a( &&r%tx-> Phi Contact Person: _So\n,r‘ 0 c e e 5bi , P t, Phone Number: (tit° ) 1 S 5" 50!I For projects with multiple basins, specify which basin this worksheet applies to: t.t)eA Pan elevations Basin Bottom Elevation aq.0 ft. (floor of the basin) Permanent Pool Elevation 3 S,n ft. (elevation of the orifice) Temporary Pool Elevation 3 to.3 to ft. (elevation of the discharge structure overflow) areas Permanent Pool Surface Area Q4,4-13 sq. ft. (water surface area at the orifice elevation) Drainage Area IS."7 S ac. (on site and off-site drainage to the basin) Impervious Area c.S) ac. (on-site and off-site drainage to the basin) volumes Permanent Pool Volume 73 ,Slob cu. ft. (combined volume of main basin and forebay) Temporary Pool Volume 3 S q(04 cu. ft. (volume detained above the permanent pool) Forebay Volume I S, O q cu. ft. (approximately 20%of total volume) Other parameters SA/DA1 3.-j-S 410 (surface area to drainage area ratio from DWQ table) Diameter of Orifice a.0 in. (2 to 5 day temporary pool draw-down required) Design Rainfall I.0 in. Design TSS Removal 2 9 0 % (minimum 85%required) Form SWU-102 Rev 3.99 Page 1 of 4 Footnotes: 1 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. 2 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 Stormwater 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. Appli is Initials a. The permanent pool depth is between 3 and 6 feet(required minimum of 3 feet). b. The forebay volume is approximately equal to 20%of the basin volume. c. The temporary pool controls runoff from the design storm event. d. The temporary pool draws down in 2 to 5 days. e. If required,a 30-foot vegetative filter is provided at the outlet(include non-erosive flow calculations) f/ P f. The basin length to width ratio is greater than 3:1. i r g. The basin side slopes above the permanent pool are no steeper than 3:1. h. A submerged and vegetated perimeter shelf with a slope of 6:1 or less (show detail). At, i. Vegetative cover above the permanent pool elevation is specified. j4 j. A trash rack or similar device is provided for both the overflow and orifice. 6[I k. A recorded drainage easement is provided for each basin including access to nearest pp right- of-way. 5 NI A 1. 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. m. A mechanism is specified which will drain the basin for maintenance or an emergency. III. 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. This system(check one) 0 does 0 does not incorporate a vegetated filter at the outlet. This system(check one) 0 does 0 does not incorporate pretreatment other than a forebay. Form SWU-102 Rev 3.99 Page 2 of 4 Maintenance activities shall be performed as follows: 1. 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 such that it will give an accurate depth reading and not readily penetrate into accumulated sediments. When the permanent pool depth reads 4.5 feet in the main pond,the sediment shall be removed. When the permanent pool depth reads 4,5 feet in the forebay,the sediment shall be removed. BASIN DIAGRAM (fill in the blanks) V Permanent Pool Elevation 3 5.0 Sediment Re oval El. 30,5 2 75 0 Sediment Removal Elevation 30.`J 75% Bottom Ele ation act.o t Bottom Elevation Q 1.0 25% FOREBAY 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. 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. Form SWU-102 Rev 3.99 Page 3 of 4 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:Adam Lisk Title: Manager-Member Cumbee Road LLC Address: 7616 Hawk Road,Wilmington, North Carolina 28411 Phone: 910-352-0634 Signature: Date: i —6` 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, Lalantio 5 • tOo ef'-S , a Notary Public for the State of Will C( i!V , County of 'Pi fi , do hereby certify that --L i 5 _ __ personally appeared before me this uday of Aut.( , , and acknowledge the due exec 'on of the forgoing wet detention basin maintenance requirements. Witness my hand and official seal, we 5 s Lin'to JP��OTARk..u)S. ® oa® PUBLNG . G ''''i A/ /� es',s I11 COUNA```�, SEAL My commission expires ' 2h. 1 iatlog Form SWIJ-102 Rev 3.99 Page 4 of 4 WET DETENTION BASIN SUPPLEMENT ADDENDUM Wet Pond#2 SECTION II: REQUIRED ITEMS CHECKLIST Replace item "k"with the following: k. Drainage easements are not required to maintain pond. Pond is accessible from the public right of way and has room for maintenance equipment around the portion of the pond that is adjacent to the right of way. Access is not possible along wetlands or adjacent property line. The entire pond can still be maintained from accessible areas. On plat,pond area will be included in the adjacent open area. SECTION III: WET DETENTION BASIN OPERATION AND MAINTENANCE AGREEMENT Add to end of list: 8. A portable pump shall be kept on-site to drain pond in the case of an emergency or to perform maintenance. Flushing of sediment through pump shall be minimized to the maximum extent practical. • Permit No. (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 i Project Name: C.Ambe.e. Q.00.A 1"�•`�2� USC act, oprnfr\\ LSec.lA)c.t,n�� �Irii eAlc,r )Q\ .I Contact Person: ,o'n r. F• 0 1 t Slti Phone Number: (9 (9 ) 7 5 5- 5-0 For projects with multiple basins, specify which basin this worksheet applies to: W A 'Pow\a elevations Basin Bottom Elevation 3q.5 0 ft. (floor of the basin) Permanent Pool Elevation +.5.5 0 ft. (elevation of the orifice) Temporary Pool Elevation 9-4. 4 a, ft. (elevation of the discharge structure overflow) areas Permanent Pool Surface Area It, 15-53 sq. ft. (water surface area at the orifice elevation) Drainage Area 5. ac. (on-site and off-site drainage to the basin) Impervious Area a. S 3 ac. (on-site and off-site drainage to the basin) volumes Permanent Pool Volume a,5,11'a cu. ft. (combined volume of main basin and forebay) Temporary Pool Volume 10, B q4 cu. ft. (volume detained above the permanent pool) Forebay Volume 5144¢ cu. ft. (approximately 20%of total volume) Other parameters SA/DA1 0/0 (surface area to drainage area ratio from DWQ table) Diameter of Orifice a•5 in. (2 to 5 day temporary pool draw-down required) Design Rainfall 1.0 in. Design TSS Removal 2 q 0 % (minimum 85%required) Form SWU-102 Rev 3.99 Page 1 of 4 Footnotes: 1 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. 2 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 Stormwater 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 a. The permanent pool depth is between 3 and 6 feet(required minimum of 3 feet). b. The forebay volume is approximately equal to 20%of the basin volume. U"xu, c. The temporary pool controls runoff from the design storm event. d. The temporary pool draws down in 2 to 5 days. e. If required,a 30-foot vegetative filter is provided at the outlet(include non-erosive flow calculations) f. The basin length to width ratio is greater than 3:1. l?, g. The basin side slopes above the permanent pool are no steeper than 3:1. h. A submerged and vegetated perimeter shelf with a slope of 6:1 or less(show detail). i. Vegetative cover above the permanent pool elevation is specified. j. A trash rack or similar device is provided for both the overflow and orifice. 1_41 k. A recorded drainage easement is provided for each basin including access to nearest right- of-way. x- N I A 1. 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. )1e1 •At2)40 m. A mechanism is specified which will drain the basin for maintenance or an emergency. III. 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. This system (check one) 0 does 0 does not incorporate a vegetated filter at the outlet. This system(check one) 0 does 0 does not incorporate pretreatment other than a forebay. Form SWU-102 Rev 3.99 Page 2 of 4 Maintenance activities shall be performed as follows: 1. 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 such that it will give an accurate depth reading and not readily penetrate into accumulated sediments. When the permanent pool depth reads 3 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. BASIN DIAGRAM ill in the blanks) 0 Permanent Pool Elevation 43.S Sediment Re oval El. .4-0.5- 2 75 0 Sediment Removal Elevation 40•'S i 75% Bottom Ele ation 31 .S t % Bottom Elevation 39.S 25% FOREBAY 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. 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. Form SWU-102 Rev 3.99 Page 3 of 4 • '. 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: Adam Lisk Title: Manager-Member Cumbee Road LLC Address: 7616 Hawk Road,Wilmington, North Carolina 28411 Phone: 910-352-0634 Signature: Date: 5.'`6` 0 7 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, Lii4anqa 3• tbater.s , a Notary Public for the State of 1Nc(1h Caf®I ilt, , County of (j , do hereby certify that Rtkti L S& tithpersonally appeared before me this day of J IA-id , A.061, and acknowledge the due exec on of the forgoing wet detention basin maintenance requirements. Witness my hand and official seal, t S h l,C.'Y0- .„„..„,„, .ac.::+CTAgy�.(PS AUg1.\Gf.••V : - ,p' _ `. '/)am••......••',4,``,� .'sss/,COUN,`;%. SEAL My commission expires firitinchq, Awe Form SWU-102 Rev 3.99 Page 4 of 4 WET DETENTION BASIN SUPPLEMENT ADDENDUM Wet Pond#3 SECTION II: REQUIRED ITEMS CHECKLIST Replace item "k"with the following: k. Drainage easements are not required to maintain pond. Pond is accessible from the public right of way. There is no room for maintenance equipment along wetlands; however,there is room along the adjacent property lines. The entire pond can be maintained from accessible areas. On plat,pond area will be included in the adjacent open area. SECTION III: WET DETENTION BASIN OPERATION AND MAINTENANCE AGREEMENT Add to end of list: 8. A portable pump shall be kept on-site to drain pond in the case of an emergency or to perform maintenance. Flushing of sediment through pump shall be minimized to the maximum extent practical. Permit No. (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: CAnmbee kkoo,,.�-1"\��ii ��ia U52. Ocue.,1,9pcntA Bee—l.JLin le. alAe,,L;of) 914 Contact Person: io\nrr F• O �es •- Phone Number: (919 ) — 60 I For projects with multiple basins, specify which basin this worksheet applies to: WEN Pof►1 # 9- elevations Basin Bottom Elevation 31 . 5O ft. (floor of the basin) Permanent Pool Elevation 4-3. 5 O ft. (elevation of the orifice) Temporary Pool Elevation 45 . 05 ft. (elevation of the discharge structure overflow) areas Permanent Pool Surface Area l �, 117 sq. ft. (water surface area at the orifice elevation) Drainage Area ac. (on-site and off-site drainage to the basin) Impervious Area 5. l 02 ac. (on-site and off-site drainage to the basin) volumes Permanent Pool Volume 3+, 13 to cu. ft. (combined volume of main basin and forebay) Temporary Pool Volume aO,-I2.5 cu. ft. (volume detained above the permanent pool) Forebay Volume 7 I(o I cu. ft. (approximately 20%of total volume) Other parameters SA/DA' a as 0/, (surface area to drainage area ratio from DWQ table) Diameter of Orifice a. in. (2 to 5 day temporary pool draw-down required) Design Rainfall 1.0 in. Design TSS Removal 2 10 % (minimum 85%required) Form SWU-102 Rev 3.99 Page 1 of 4 Footnotes: 1 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. 2 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. IL REQUIRED ITEMS CHECKLIST The following checklist outlines design requirements per the Stormwater 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 611411.A., a. The permanent pool depth is between 3 and 6 feet(required minimum of 3 feet). b. The forebay volume is approximately equal to 20%of the basin volume. c. The temporary pool controls runoff from the design storm event. t '8 d. The temporary pool draws down in 2 to 5 days. 10 j e. If required, a 30-foot vegetative filter is provided at the outlet(include non-erosive flow calculations) • f. The basin length.to width ratio is greater than 3:1. g. The basin side slopes above the permanent pool are no steeper than 3:1. Oretf. h. A submerged and vegetated perimeter shelf with a slope of 6:1 or less(show detail). i. Vegetative cover above the permanent pool elevation is specified. • j. A trash rack or similar device is provided for both the overflow and orifice. GIs k. A recorded drainage easement is provided for each basin including access to nearest right- of-way. ''E See Aa�e,n N IA 1. 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. m. A mechanism is specified which will drain the basin for maintenance or an emergency. III. 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. This system(check one) 0 does 0 does not incorporate a vegetated filter at the outlet. This system(check one) 0 does 0 does not incorporate pretreatment other than a forebay. Form SWU-102 Rev 3.99 Page 2 of 4 Maintenance activities shall be performed as follows: 1. 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 such that it will give an accurate depth reading and not readily penetrate into accumulated sediments. When the permanent pool depth reads 4,S feet in the main pond,the sediment shall be removed. When the permanent pool depth reads 4,' feet in the forebay,the sediment shall be removed. BASIN DIAGRAM �11 in the blanks) 0 Permanent Pool Elevation 43.S Sediment Re oval El. 31.0 75 0 Sediment Removal Elevation 31.0 75% Bottom Ele ation 37,' Bottom Elevation 31,5 25% FOREBAY 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. 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. Form SWU-102 Rev 3.99 Page 3 of 4 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:Adam Lisk Title: Manager-Member Cumbee Road LLC Address:7616 Hawk Road,Wilmington, North Carolina 28411 Phone: 910-352-0634 Signature: Date: 6— 6' - 0 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, La,-)-anit 5 - axtfers , a Notary Public for the State of 1\16 h. (1 r®IIka , County of-1)1 i{ , do hereby certify that Pt 1.45 L til personally appeared before me this day of J LW ,RCM, and acknowledge the due exec ion of the forgoing wet detention basin maintenance requirements. Witness my hand and official seal, , 4-1,tiat S . (1)CLLKA4 �oo� llioloo,, „.• `l P S w r�',o . ..••........II' ,, w `. Q-: N• OTARY . cn o▪ PUBLIC' %,'<i •1 ? `1'° COUNT��`� -1,H i t n NN�- SEAL My commission expires nrViiiCh 1 r1 , g' Form SWU-102 Rcv 3.99 Page 4 of 4 WET DETENTION BASIN SUPPLEMENT ADDENDUM Wet Pond#4 SECTION H: REQUIRED ITEMS CHECKLIST Replace item "k"with the following: k. Drainage easements are not required to maintain pond. Pond is accessible from the public right of way. There is no room for maintenance equipment along wetlands; however,there is room along the adjacent property lines. The entire pond can be maintained from accessible areas. On plat,pond area will be included in the adjacent open area. SECTION III: WET DETENTION BASIN OPERATION AND MAINTENANCE AGREEMENT Add to end of list: 8. A portable pump shall be kept on-site to drain pond in the case of an emergency or to perform maintenance. Flushing of sediment through pump shall be minimized to the maximum extent practical. Permit No. (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: C►rntne-e. ((OD - Q USe. Dc.ve)ocdn r\A (Sea, lA.)(frac Plat c,,A1c n.) 914.I Contact Person: iohr, F. 01eSb.-1 Phone Number: (9 I9 ) -155- ST01 l For projects with multiple basins, specify Which basin this worksheet applies to: Ul7Or i0or, elevations Basin Bottom Elevation ` 6.0 ft. (floor of the basin) Permanent Pool Elevation 4-$ . 0 ft. (elevation of the orifice) Temporary Pool Elevation `f S S.5$ ft. (elevation of the discharge structure overflow) areas Permanent Pool Surface Area 101g,Q 01 sq. ft. (water surface area at the orifice elevation) Drainage Area a •5°1 ac. (on-site and off-site drainage to the basin) Impervious Area t • US ac. (on-site and off-site drainage to the basin) volumes Permanent Pool Volume l S,44 t cu. ft. (combined volume of main basin and forebay) Temporary Pool Volume to a 80 cu. ft. (volume detained above the permanent pool) Forebay Volume 3) 33 S cu. ft. (approximately 20%of total volume) Other parameters SA/DA1 1.65 e lv (surface area to drainage area ratio from DWQ table) Diameter of Orifice a e a in. (2 to 5 day temporary pool draw-down required) Design Rainfall 1 . D in. Design TSS Removal 2 10 % (minimum 85%required) Form SWU-102 Rev 3.99 Page 1 of 4 Footnotes: 1 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. 2 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 Stormwater 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 a. The permanent pool depth is between 3 and 6 feet(required minimum of 3 feet). b. The forebay volume is approximately equal to 20%of the basin volume. c. The temporary pool controls runoff from the design storm event. d. The temporary pool draws down in 2 to 5 days. e. If required,a 30-foot vegetative filter is provided at the outlet(include non-erosive flow calculations) f. The basin length to width ratio is greater than 3:1. g. The basin side slopes above the permanent pool are no steeper than 3:1. h. A submerged and vegetated perimeter shelf with a slope of 6:1 or less (show detail). �C. i. Vegetative cover above the permanent pool elevation is specified. :(.ii j. A trash rack or similar device is provided for both the overflow and orifice. a k. A recorded drainage easement is provided for each basin including access to nearest right- of-way. See N I A 1. 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. '10101�? m. A mechanism is specified which will drain the basin for maintenance or an emergency. III. 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. This system(check one) 0 does 0 does not incorporate a vegetated filter at the outlet. This system(check one) 0 does 0 does not incorporate pretreatment other than a forebay. Form SWU-102 Rev 3.99 Page 2 of 4 Maintenance activities shall be performed as follows: 1. 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 such that it will give an accurate depth reading and not readily penetrate into accumulated sediments. When the permanent pool depth reads a.a D feet in the main pond,the sediment shall be removed. When the permanent pool depth reads Q.ac feet in the forebay,the sediment shall be removed. BASIN DIAGRAM (fi11 in the blanks) 0 Permanent Pool Elevation 41.t.,0 Sediment Re oval El. 45,7-5 :75 0 3 Sediment Removal Elevation 9-5,-6 75% Bottom Ele ation 4 % .C7 Bottom Elevation g'j!� 25% FOREBAY 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. 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. Form SWU-102 Rev 3.99 Page 3 of 4 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:Adam Lisk Title: Manager-Member Cumbee Road LLC Address: 7616 Hawk Road,Wilmington, North Carolina 28411 Phone: 910-352-0634 Signature: Date: 6 C 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, ta.-1-0Ria 3, V:u ea , a Notary Public for the State of 1V- Cai' 11 fitt, County of l}F , do hhe� MO certify that {In Ll. personally appeared before me this Liz day of J(,�y� , "IQ''l, and acknowledge the due execution of the forgoing wet detention basin maintenance requirements. Witness my hand and official seal, 01\it,4Ct itIS LaiM _ow Nipplio %JQ�o7ARy 9N .o PUBL\G /U /�•• ••• �i�J`COUN \a‘% SEAL My commission expires (1 13 ci 11 2 Form SWU-102 Rev 3.99 Page 4 of 4 WET DETENTION BASIN SUPPLEMENT ADDENDUM Wet Pond#5 SECTION II: REQUIRED ITEMS CHECKLIST Replace item "k"with the following: k. Drainage easements are not required to maintain pond. Pond is accessible from the public right of way. There is no room for maintenance equipment along wetlands; however,there is room along the adjacent property lines. The entire pond can be maintained from accessible areas. On plat,pond area will be included in the adjacent open area. SECTION III: WET DETENTION BASIN OPERATION AND MAINTENANCE AGREEMENT Add to end of list: 8. A portable pump shall be kept on-site to drain pond in the case of an emergency or to perform maintenance. Flushing of sediment through pump shall be minimized to the maximum extent practical.