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HomeMy WebLinkAboutSW8080107_HISTORICAL FILE_20080201STORMWATER DIVISION CODING SHEET POST -CONSTRUCTION PERMITS PERMIT NO. SW8 Dj�OI,O_J- DOC TYPE ' ❑ CURRENT PERMIT ❑ APPROVED PLANS HISTORICAL FILE ❑ COMPLIANCE EVALUATION INSPECTION DOC DATE 2Q7�O O\ YYYYMMOD �pF W A rFRO Michael P. i asley, Governor `Q G William G. Ross Jr., Secretary CO 7 North Carolina Department of Environment and Natural Resources `i 0 Coleen H. Sullins Director NWOMPliftr Division of Water Quality February 1, 2008 Robert C. G. Exum ZDV, Inc. P.O. Box 1967 Wilmington, NC 28402 Subject: Permit No. SW8 080107 Hwy 74 Alligator Branch Bridge Temporary Drive Low Density Stormwater Project Brunswick County Dear Mr. Exum: The Wilmington Regional Office received a complete Stormwater Management Permit Application for Hwy 74 Alligator Branch Bridge Temporary Drive on January 3, 2008. 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 080107 dated. February 1, 2008, for the construction of the subject project. This permit shall be effective from the date of issuance until rescinded and shall be subject to the conditions and limitations as specified therein, and does not supercede any other agency permit that may be required. 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 sixty (60) days following receipt of this permit. This request must be in the form of a written petition, conforming to Chapter 1508 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 either David Cox or me at (910) 796-7215. Sinc ly, Edward eck Regional Supervisor Surface Water Protection Section ENBldwc: S:1WQSISTORMWATIPERMIT1080107.feb08 cc: Lawrence Gilman Brunswick County Inspections David Cox Wilmington Regional Office-- Central Files NorlhCafolina ,A7Aturully North Carolina Division of Water Quality 127 Cardinal Drive Extension Wilmington, NC 28405 Phone (910) 796.7215 Customer Service Wilmington Regional Office Internet: www.newatergwtl_iiy.orL, Fax (910) 350-2004 1-877-623-6748 An Equal Opportunity/Affirmative Action Employer— 50% Recycled110% Post Consumer Paper State Stormwater Management Systems Permit Number SW8 080107 STATE OF NORTH CAROLINA DEPARTMENT OF ENVIRONMENT AND NATURAL RESOURCES DIVISION OF WATER QUALITY STATE STORMWATER MANAGEMENT PERMIT LOW 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 Robert C. G. Exum & ZDV, Inc. Hwy 74 Alligator Bridge Temporary Drive Hwy74 Brunswick County FOR THE construction, operation and maintenance of a low density development 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. The Permit shall be effective from the date of issuance until rescinded and shall be subject to the following specific conditions and limitations: I. DESIGN STANDARDS 1. This permit covers the construction of 108,687 square feet of built -upon area. 2. The overall tract built -upon area percentage for the project must be maintained at 24%, as required by Section .1005 of the stormwater rules. 3. Approved plans and specifications for projects covered by this permit are incorporated by reference and are enforceable parts of the permit. 4. The only runoff conveyance systems allowed will be vegetated conveyances such as swales with minimum side slopes of 3:1 (H:V) as defined in the stormwater rules and approved by the Division. 5. No piping is allowed except that minimum amount necessary to direct runoff beneath an impervious surface such as a road or to provide access. 6. Unless specified elsewhere, permanent seeding requirements for the swales must follow the guidelines established in the North Carolina Erosion and Sediment Control Planning and Design Manual. 7. Roof drains must terminate at least 30 foot from the Mean High Waterline. Page 2of5 State Stormwater Management Systems Permit Number SW8 080107 II. SCHEDULE OF COMPLIANCE 1. Projects covered by this permit will maintain a.minimum 30-foot wide vegetative buffer between all impervious areas and surface waters. 2. The permittee is responsible for verifying that the proposed built -upon area does not el teed the allowable built -upon area. 3. 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 shall1provide copies of revised plans and certification in writing to the Director that the changes have been made. 4. Prior to the subdivision and/or sale of this project, in whole or in part, the folio ing deed restrictions must be recorded with the Office of the Register of Deeds: a. The following covenants are intended to ensure ongoing compliance with State Stormwater Management Permit Number SW8 080107, as issued by the Division of Water Quality under NCAC 2H.1000. b. The State of North Carolina is made a beneficiary of these covenants to the extent necessary to maintain compliance with the Stormwater Management Permit. C. These covenants are to run with the land and be binding on all persons and parties claiming under them. d. The covenants pertaining to stormwater may not be altered or rescinded without the express written consent of the State of North Carolina, Division of Water Quality. e. Alteration of the drainage as shown on the approved plans may not take place without the concurrence of the Division of Water Quality. f. Lots within CAMA's Area of Environmental Concern may have the permitted maximum built -upon area reduced due to CAMA jurisdiction within the AEC. g. Construction of additional built -upon area in excess of 108,687 square feet will require a permit modification. h. Construction of additional impervious areas such that low -density requirements are no longer met must be submitted to DWQ and a permit modification must be issued prior to construction. An engineered system will be required to collect and treat the runoff from all built -upon area associated with the project, including that area permitted under the low density option. i. Filling in or piping of any vegetative conveyances (ditches, swales, etc.) associated with this development, except for average driveway crossings, is strictly prohibited by any persons. j. A minimum 30' wide vegetated buffer area shall be provided between surface waters and all impervious surfaces. Page 3 of 5 State Stormwater Management Systems Permit Number SW8 080107 5. A copy of the recorded restrictions must be received in this Office within 30 days of the date of sale. 6. Filling in or piping of any vegetative conveyances (ditches, swales, etc.) associated with the permitted development, except for average driveway crossings, is strictly prohibited by any persons. 7. Projects within CAMA's Area of Environmental Concern (AEC) are subject to a reduction of the permitted amount of built -upon area due to CAMA jurisdiction within the AEC. 8. 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 the approved plans, regardless of size. b. Project name change. C. Transfer of ownership. d. Redesign or addition to the approved amount of built -upon area. e.. Further subdivision, acquisition, or sale of the project area. The project area is defined as all property owned by the permittee, for which Sedimentation and Erosion Control Plan approval was sought. f. Filling in, altering or piping any vegetative conveyance shown on the approved plan. 9. Swales and other vegetated conveyances shall be constructed in their entirety, vegetated, and be operational for their intended use prior to the construction of any built -upon surface. 10. During construction, erosion shall be kept to a minimum and any eroded areas of the swales or other vegetated conveyances will be repaired immediately. 11. The permittee shall at all times provide the operation and maintenance necessary to operate the permitted stormwater management systems at optimum efficiency to include: a. Inspections b Sediment removal. C. Mowing, and re -vegetating of the side slopes. d. Immediate repair of eroded areas. e. Maintenance of side slopes in accordance with approved plans and specifications. 12. Within 30 days of completion of the project, the permittee shall certify in writing that the project has been constructed in accordance with the approved plans. 13. The permittee shall submit all information requested by the Director or his representative within the time frame specified in the written information request. III. GENERAL CONDITIONS Failure to abide by the conditions and limitations contained in this permit may subject the Permittee to an enforcement action by the Division of Water Quality, in accordance with North Carolina General Statutes 143-215.6A to 143-215.6C. 2. The permit issued shall continue in force and effect until revoked or terminated. Page 4of5 State Stormwater Management Systems Permit Number SW8 080107 3. The permit may be modified, revoked and reissued or terminated for cause. The filing of a request for a permit modification, revocation and re -issuance, or termination does not stay any permit condition. 4. The issuance of this permit does not prohibit the Director from reopening and modifying the permit, revoking and reissuing the permit, or terminating the permit as allowed by the laws, rules, and regulations contained in Title 15A of the North Carolina Administrative Code, Subchapter 2H.1000; and North Carolina General Statute 1437215.1 et. al. 5. This permit is not transferable except after notice to and approval by the Director. The Director may require modification or revocation and re -issuance of the permit to change the name and incorporate such other requirements as may be necessary. A formal permit request must be submitted to the Division of Water Quality accompanied by the appropriate fee, documentation from both 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 the Director approves the transfer. 6. The permittee grants permission to DENR Staff to enter the property for the purpose of inspecting all components of the stormwater management facility. 7. The permittee shall notify the Division of any name, ownership or mailing address chanes within 30 days. issuance 8. The 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. Permit issued this the 1st day of February, 2007 NORT AROLINA EN RONMENTAL MANAGEMENT COMMISSION ------�-_1.91,Lt._�!____--------------------------- for Coleen H. Sullins, Director Division of Water Quality B',y Authority of the Environmental Management Commission Perrhit Number SW8 080107 Page 5 of 5 DWQ USE ONLY Date Received Fee Paid Permit Number 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. Applicants name (specify the name of the corporation, individual, etc. who owns the project): ZDV, Inc. 2. Print Owner/Signing Official's name and title (person legally responsible for facility and compliance): Robert C.G. Exum 3. Mailing Address for person listed in item 2 above: P.O. Box 1967 City:�Wilmingon State. N.C. Zip: 28402 Phone: 910 392-9325 Fax: ( ) Email: 4. Project Name (subdivision, facility, or establishment name - should be consistent with project name on plans, specifications, letters, operation and maintenance agreements, etc.): Highway 74 Alligator Branch Bridge Temporary Drive for project access 5. Location of Project (street address): North side of Highway 74 City: 6. Directions to project (from nearest major intersection): County: Brunswick Approximate_,y three quarters of a mile WNW of the east end of S.R.1417 (Malmo Loop Rd.) 7. Latitude: 34016.246' N Longitude: 78006.281' W of project 8. Contact person who can answer questions about the project: Name: Robert C.G. Exum Telephone Number: ( 910 ) 392-9325 Email: II. PERMIT INFORMATION: 1. Specify whether project is (check one): ®New ❑Renewal []Modification Form SWU-101 Version 8.07 Page l 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) 3. Specify the type of project (check one): ®Low Density ❑High Density ❑Redevelop ❑General Permit ❑Universal SMP ❑Other 4. Additional Project Requirements (check applicable blanks): ❑CAMA Major ❑Sedimentation/Erosion Control 0404/401 Permit ❑NPDESStormwater 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. Road side ditches will divert storm water to sediment traps which will be located along proposed gravel road. _ 2. Stormwater runoff from this project drains to the Cape Fear River basin. 3. Total Site Area: 40.85 acres 4. Total Wetlands Area: 8.76 acres 5. 100' Wide Strip of Wetland Area: 7.13 6. Total Project Area**: 39.22 acres acres (riot applicable if no wetlands exist on site) 7. Project Built Upon Area: 8. How many drainage areas does the project have? 1 6.4 % 9. 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 Alligator Branch Stream Class & Index No. C; SW Drainage Area (so 39.22 Ac. (1,708,288 so Existing Impervious* Area (so 0 Proposed Impervious*Area (so 2.50 Ac. (108,687 sf) % Impervious* Area (total) 6.36 Impervious* Surface Area Drainage Area 1 Drainage Area 2 On -site Buildings (sf) 0 On -site Streets (so 2.50 Ac. (108,687 so On -site Parking (so 0 On -site Sidewalks (so 0 Other on -site (so 0 Off -site (so 0 Total (so: 2.50 Ac. (108,687 so * Impervious area is defined as the built upon area including, but not Iimited to, buildings, roads, parking areas, sidewalks, gravel areas, etc. **Total project area shall be calculated based on the current policy regarding inclusion of wetlands in the built upon area percentage calculation. Form SWU-101 Version 8.07 Page 2 of 4 10. How was the off -site impervious area listed above derived? N/A ^ IV. DEED RESTRICTIONS AND PROTECTIVE COVENANTS One of the following 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. Form DRPC-1 High Density Commercial Subdivisions Form DRPC-2 High Density Developments with Outparcels Form DRPC-3 High Density Residential Subdivisions Form DRPC-4 Low Density Commercial Subdivisions Form DRPC-5 Low Density Residential Subdivisions Form DRPC-6 Low Density Residential Subdivisions with Curb Outlets By your signature below, you certify that the recorded deed restrictions and protective covenants for this project shall include all the applicable items required in the above form., 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 $MP specified for this project. Contact the Stormwater and General Permits Unit at (919) 733-5083 for the status and availability of these forms. Form SW401-Low Density Low Density Supplement Form SW401-Curb Outlet System Curb Outlet System Supplement Form SW401-Off-Site System Off -Site System Supplement Form SW401-Wet Detention Basin Wet Detention Basin Supplement Form SW401-Infiltration Basin Infiltration Basin Supplement Form SW401-Infiltration Trench Underground Infiltration Trench Supplement Form SW401-Bioretention Cell Bioretention Cell Supplement Form SW401-Level Spreader Level Spreader/Filter Strip/Restored Riparian Buffer Supplement Form SW401-Wetland Constructed Wetland Supplement Form SW401-Grassed Swale Grassed Swale Supplement Form SW401-Sand Filter Sand Filter Supplement Form SWU-101 Version 8.07 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 Office. (Appropriate office may be found by locating project on the interactive online map at http://h2o.enr.state.nc.us/su/msi_maps.htm) 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 I-e- • Original and one copy of the Deed Restrictions & Protective Covenants Form 0*1 • Original of the applicable Supplement Form(s) and O&M agreement(s) for each BMP G • Permit application processing fee of $505 ($4,000 for Express) payable to NCDENR • Calculations & detailed narrative description of stormwater treatment/management • Copy of any applicable soil report • Three copies of plans and specifications (sealed, signed & dated), 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 - Original contours, proposed contours, spot elevations, finished floor elevations - Details of roads, drainage features, collection systems, and stormwater control measures - Wetlands delineated, or a note on plans that none exist - Existing drainage (including off -site), drainage easements, pipe sizes, runoff calculations - Drainage areas delineated - Vegetated buffers (where required) VII. AGENT AUTHORIZATION If you wish to designate authority to another individual or firm so that they may provide information on your behalf, please complete this section. Designated agent (individual or firm): Cape Fear Engineering, Inc. Mailing Address: 151 Poole Rd, Suite 100 City: Belville State: NC Zip: 28451 Phone: ( 910 ) 383-1044 Email: VIII. APPLICANT'S CERTIFICATION Fax: ( 910 ) 383-1045 - I, (print or type name of person listed in General Information, item 2) _ Robert C.G. 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. C Date: /L- 31-07 Form SWU-101 Version 8.07 Page 4 of 4 ALLIGATOR BRIDGE PROJECT TEMPORARY DRIVEWAY Low Density Storm -Water Plan 5ubmlttal Project areaNctland Calculations 51te Area (TOTAL) _ 1,779,233 s . ft 40.85 acres Wetland Area (TOTAL) = 1381 ,472 51. ft 8.7G acres 2517 RULE 1,779,233 x 0.25 = 444,806 51. ft. 10.21 acres 8.7G acres Is less than 1 0.2 1 acres OKAY 00' RULE Exlstln area within a 100' offset of the wetland line = 310,527 5CI. ft. 7. 1 3 acres 7. 1 3 acres Is less than 8.7G acres OKAY ONLY 310,527 5 . ft. 7.13 acres of wetlands may be included within the ro ect area; THEREFORE: Total Project Area = 1,779,233 - 381 ,472 + 310,527 = 1 ,708,288 s . ft. 1,705,288 5CI. ft. 1 / 43,5GO 5 . ft./acre = 39.22 acres I /3/2008 I of I 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 LOW DENSITY SUPPLEMENT This form may be photocopied for use as an original A low density project is one that meets the appropriate criteria for built upon area and transports stormwater runoff primarily through vegetated conveyances. Low density projects should not have a discrete stormwater collection system as defined by 15A NCAC 2H .1002(18). Low density requirements and density factors can be found in 15A NCAC 2H .1005 through .1007, DWQ BMP Manual (2007), and Session Law 2006-246. I. PROJECT INFORMATION Project Name : _ Highway 74 Alligator Branch Bridge Temporary Drive for projectaccess Contact Person: Robert C.G. Exum Phone Number: 910 392-9325 Number of Lots: I Allowable Built Upon Area Per Lot*: *If lot sizes are not uniform, attach a table indicating the number of lots, lot sizes and allowable built upon area for each lot. The attachment must include the project name, phase, page numbers and provide area subtotals and totals. BUA shall be shown in units of square feet. II. BUILT UPON AREA See the Stormwater Management Permit Application for specific language that must be recorded in the deed restrictions for all subdivisions. For uniform lot sizes, complete the following calculation in the space provided below where: • SA Site Area - the total project area above Mean High Water. Wetlands may be excluded when the development results in high density pockets. • DF Density Factor - the appropriate percent built upon area divided by 100. • RA Road Area - the total impervious surface occupied by roadways. • OA Other Area - the total area of impervious surfaces such as clubhouses, tennis courts, sidewalks, etc. • No. Lots - the total number of lots in the subdivision. • BUA/Lot - the computed allowable built upon area for each lot including driveways and impervious surfaces located between the front lot line and the edge of pavement. Fnrm SW401-l.nw nemity-Rev. Pace t of 3 (SA x DF) - RA - OA = BUA No. Lots Lot Calculation: (SA: 1,779,426.00 ft2 x DF: 0.24)- (RA: Iw900.00 ft2) — (OA: 0 f 2 = BUA per Lot = 318,162.24 ft2 (No of Lots: 1 ) III. REQUIRED ITEMS CHECKLIST Initial in the space provided to indicate that the following requirements have been met and supporting documentation is provided as necessary. Indicate the page or plan sheet number where supporting documentation can be found. If the applicant has designated an agent on the Stormwater Management Permit Application Form, the agent may initial below. Page/Plan Initials Sheet No. ( a. A 30 foot vegetative buffer is provided adjacent to surface waters. Projects in the Neuse, Tar -Pamlico, Catawba River basins, and Randleman Lake may require additional buffers. b. Deed restriction language as required on form SWU-101 shall be recorded as a restrictive covenant. A copy of the recorded document shall be provided to DWQ within 30 days of platting and prior to sale of any lots. 1�C c. Built upon area calculations are provided for the overall project and all lots. i d. Project conforms to low density requirements within the ORW AEC (if applicable). [15A NCAC 2H .1007(2)(b)] i e. Side slopes of swales are no steeper than 3:1. _ I f. Longitudinal slope of swales is no greater than 5%; calculations for shear stress and velocity are shown if slope is greater than 5%. g. Swales are designed to carry, at a non -erosive velocity, at least the 10-year storm. 1 h. Swale detail and permanent vegetation is specified on the plans. Fnrm RW401-Lm Density -Rev. PAae. 9. of I IV. SWALE SYSTEM MAINTENANCE REQUIREMENTS 1. Mowing will be accomplished as needed according to the season. Grass height will not exceed six inches at any time. 2. Swales will be inspected monthly or after every runoff producing rainfall event for sediment build-up, erosion, and trash accumulation. 3. Accumulated sediment and trash will be removed as necessary. Swales will be reseeded or sodded following sediment removal. 4. Eroded areas of the swaies will be repaired and reseeded. Swales will be revegetated as needed and in a timely manner based on the monthly inspections. Catch basins, curb cuts, velocity reduction devices, and piping will be inspected monthly or after every significant runoff producing rainfall event. Trash and debris will be cleared away from grates, curb cuts, velocity reduction devices and piping. 6. Swales will not be altered, piped, or filled in without approval from NCDENR Division of Water Quality. I acknowledge and agree by my signature below that I am responsible for the performance of the six 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 and Title:_ Robert C.G. Exum, Member/Manager Address:_ P.O. Box 1967, Wilmington, NC 28402 Phone: (910) 392-9325 Dater Signature: 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, J Lo7►r n ro— , a Notary Publicforthe /aState of /��0 CgrolMu: , County of &W OVee_ do hqreby certify that r�DU�CT C t3 *um personally appeared before me this _ day of 314 Ve . , �, and acknowledge the due execution of the forgoing infiltration basin maintenance requirements. Witness my hand and official seat, My commission expires &re,4 z�%Z Fnrm SW401-1.nw Density-Rev.7. Pasye I of I St®rmwater Design Narrative Subject: ALLIGATOR BRIDGE Temporary drive/access Project Brunswick County, North Carolina Prepared for ZDV, Inc. P.O. Box 1967 Wilmington, NC 28402 (910)392-9325 Date::dctoblri 2W ., Y•'r, �_ ':�� ,mil , --� '�� .y '� Prepared by. Cape Fear Engineering, Inc, 151 Poole Roast, Suite 100 Belville, NC 28451 (910) 383-1044 DESIGN NARRATIVE General: The project site is located on the north side of US Highway 74/76 approximately one -tenth of a mile WNW of the east end of Malmo Loop Road (SR 1417) within Brunswick County, North Carolina. The project area to be disturbed is approximately 4.13 acres, including the sediment trap areas. Drainage considerations are to be in accordance with DEM storm water requirements. The intent of this project is to provide vehicular access, for construction vehicles, to the proposed bridge crossing Alligator Branch. The road will be constructed of gravel through the entire length. The purpose being to construct the raised bridge over Alligator Branch, and to minimize to the extent possible, any disturbance of the wetland strip and the branch at the crossing. Access from the north end will be through the area north and east of the crossing which is presently operating on a separate clearing and grubbing permit. There will be no discreet collection system constructed in association with this project. Existing Site: Site topography in the area is relatively flat. There is a ridge that transects the property south of the branch. Slopes are typically less than five (5) percent with the steeper slopes being adjacent to the branch. The area from the transecting ridge toward the wetlands is divided into small, easily manageable drainage sub -areas by several more ridges that run from the main ridge — west to the wetland boundary. Vegetation consists of a loblolly pine — oak Canopy with the understory including dogwoods, sassafras, huckleberry, panicum grasses and lichens. Subsurface soils are mapped as Baymeade and Blanton fine sands. These soils are well -drained to moderately well drained soils which have typically slow surface run-off. in the area along the branch the soils are mapped as Muckalee Loam (hydric). It is our intention to disturb this area very little and to control any sediment -laden run-off with silt fences along the wetland boundary. Proposed Improvements: Improvements proposed are a 26' wide temporary gravel access road with a 100 foot square gravel pad to "set-up" construction equipment and as a storage area for the materials necessary for the construction of the raised bridge. Drainage Calculation Considerations: Drainage on the site will sheet flow to and across the road to a roadside swale or to silt fences where the slopes are flatter and near the top of the drainage divides. Erosion Control Considerations: The road -side swales will convey run-off to the temporary sediment traps. Areas that are flatter and near the top of the drainage divides will be protected with silt fence and in one case a temporary diversion will direct run-off from a swale to a sediment trap. All the areas are naturally small and manageable. Disturbance will be held to a minimum. Once complete the gravel will be removed from the area and disposed of properly. The disturbed area will then be filled with the topsoil strippings from the future permanent road, and fertilized, mulched and seeded according to the specifications and season. Erosion Control Measures and Sequence: a. Temporary construction entrance. b. Temporary sediment basins. C. Silt fence. d. A temporary diversion earthen dike. e. Temporary seeding should construction be halted for the specified time limit (refer to specifications) f. Temporary erosion control measures shall not be removed until the future road has been completed and the area is restored to it's previous condition a good vegetative ground cover has been established. Maintenance Considerations: During construction, the Contractor shall be required to inspect and repair as needed all erosion control devices after any significant rain event. Any measure found not performing its intended function should be repaired immediately. Upon completion of construction and establishment of permanent ground cover, the Owner shall be responsible for maintenance on the project site. 2 2 C C C O d f� 2 C C C D a 78IU7.000' W 78007.000' W +78VU6.0UU' W// I � 1 1 L MalmoK 98 ` t BM 74.i Vni Bll " 20.3 78406_000' w } WG584 78'U5.000' W 1 Wr.gR4 7Rons_nnn' w li` n n s i VI1LE 9: 000 FEEI 0 _ 500_ _ _ --- i000 METEM Map created vith TO?OM C_1003 \atiomi Geographic (a1«.szatienalQeagraphic-ccm topo) L.oc.AripQ MC i� r� Storm Drain Calculations ALLIGATOR BRIDGE PROJECT TEMPORARY DRIVEWAY Low Den51t Storm -Water Plan 5ubmlttal Ditch Calculations Column = 1 "2" "3° "4„ 11 "501 11G11 „7„ -1 811 „9„ 10„ I 1 1 2, ralna e mperv�ovs rase uno oe . ime of COE] o e e e oa y DITCH Area {ac) Area (ac) Area {ac) u Tc (min) I I 0 (in/hr) Q {cfs) L {ft) N (ft) 5 y (ft) V (f s} I 0.96 0.22 0.74 0.31 20 5.04 I .52 344 3.7 0.01 i 0.41 1.75 2 0.90 O.IB 0.72 0.30 12 6.00 I.62 300 ® 0.027 0.3G 2.54 3 I.55 0.18 1.37 0.2G 14 5.73 2.29 300 2.7 0.009 0.50 1.84 4 1 ,56 0.09 I .47 0.23 10 6.30 2.25 150 ® 0.027 0.40 2.7G 5 2.61 0.77 1.84 0.35 24 4.67 4.23 47G 8.3 0.017 0.55 2.75 6 0.33 0.10 0.23 0.35 9 G.46 0.75 152 3.6 0.024 11 0.27 2.00 5ee sheet 2 of 2 '5ample Calculations" for calculatlon procedure PAG551G55-05 WEST 5RIDGEICALC5� 5wale-CAC5-10-30-07,A5 12/31 /2007 1 of 2 Sheet 2 of 2 Sample Calculations (Ditch #1) Columns correspond to attached spreadsheet. C (Column "4 C = Composite rational runoff coefficient = (Impervious area (Column "2') * 0. 70 + Pervious area (Column "3') * 0.20)/Drainage area (Column "I') = 0.31 The Flow -rate was calculated using the following Intensity equation: Im (Column "6') (Wilmington IDF) Ilo = Rainfall intensity (in/hr) = 252 = 5.04 in./hr (T, + 30) Tc (Column "5 ") = Time of concentration (min) Tc = 20 min. Q (Column "7') Q = Flow -rate (cfs) = C (Column "4') * 1(Column "6') *A (Column "I') =0.31 *5.04in/hr*0.96ac=1.52cfs The depth of flow was calculated by reworking the following equations: Depth (Column "11 ' ) Depth (f) = y Use Manning s equation to solve for y: Q= 1.49A*RY *SY=1.52cfs n Stormwater Calculations n = Manning's roughness coefficient = 0.03 A = Cross sectional area offlow (s)q = (Bottom width * Depth) + (Side slope ratio Depth2) = 0 + 5 y 2 R = Hydraulic radius (f) = A P P = Wetted perimeter (ft) = Bottom width + 2 * Depth *1 +Side slope ratioZ = 0 + 2y 1 + 52 therefore R = 0.49y L (Column "8') = Length of run (ft) = 344 ft H (Column "9') = Elevation change (f) = 3.7ft S (Column "10') = Longitudinal slope (ft/ft) = 0.011 Reformulate Manning's equation: y=0.41ft The velocity was calculated using the following equation: Velocity (Column "12') V = Velocity (fps) V = Q =1.78 fps IDFEguation from H. R. Malcom, P.E. — December 31, 19y2 — attached Run-off Coefficient: Pervious areas —from H. R. Malcom, P. E. Woods — sparse ground litter — 0.20 Brunswick County Storm -Water Manual Gravel Road (same as brick) — 0.70 Time of concentration derived from Table 5.3 Mean Flow Velocity (Brunswick County SW Manual) *For Gravel Roads a median value between Pavement/Concrete and Graded Bare Ground was used. Stormwater Calculations CAPE FEAR 'j Engineering, Inc. 151 Poole Road, Suite 100 8eMile, NC 28451 TEL (910} 383.10" FAX (910) 363.1045 www, cape fearengineering. com NC Division of Water Quality Surface Water Protection Section David Cox F t;Zi JAN 4 3 2008 �v. Transmittal Date: 11 /03/08 File: T�^ Subject: Alligator Bridge Project Temporary Driveway ❑ As Requested ❑ For Your Files ❑ For Distribution ® For your Review / Action / Approval ❑ Sent via Mail ❑ Sent via Courier Quantity Drawing No. Description 1 Revised Page 2 of Stormwater Application 1 Wetland Calculations 1") V REMARKS CC: Cape Fear Engineering, Inc. File: Signed: 4& G{/ Received By: Date: 1 r CAPE FEAR Engineering, Inc. 151 Poole Road, Susie 100 TEL (910} 383-1044 I��J FAX (910) 383.1045 www-capefearengineering. com To: JNCDENR 127 Cardinal Drive Ext. Wilmington, NC 28405-3845 Attn: I Water Quality Division /& ef���h� f(C tj 11310$ Transmittal Date: December 31, 2007 File: 655-09 "36" Subject: Highway 74 West Tract Alligator Branch Bridge Road ❑ As Requested ❑ For Your Files ❑ For Distribution ® For your Review 1 Action 1 Approval ❑ Sent via Mail ® Sent via Courier Quantity Drawing No. Description 3 Copies SWEC Plan 2 One original and one copy of Stormwater Management Permit App. 1 Low Density Supplement 1 Stormwater Design Narrative and Calcs 1 Check for $505.00 REMARKS CC: File: 655-09 "36" JAN 0 2 2008 BY: Cape Fear Engineering, Inc. Signed.__ Scott Kennedy Received By: Date: 1@4PORARY SEEDINS SCNECK LE. seredkn.3 Mixture Species Rate(b/acre) Dates Rye (grain) 120 Dec. 1 - April 15 Kobe Lespedeza 50 Dec. I - April 5 German Millet 40 April. B - Aug. B Rye (grain) 120 Aug. 5 - Dec 30 Soil Amendments Fallow reloommendations of soil tests or apply 2~ lb/acre ground agricultural limestone and 150 b/acre LO-10-10 fertilizer. Mulch Apply 4~ lb/acres straw. Anchor straw .by taidcing with asphalt, netting, or a mulch anchoring too. A disk with blades set nearly straight can be used as a mulch anchoring tool. Maintenance FWartilize If growth Is not fUlhj adequate. Reseed, rafertilize and mulch Wwiedlateiy following erosion or other damage. Topdrese with 50 lb/Acre of nitrogen in march. *NOTE. IF WIRE FENCING IS OMITTED AND ONLY SYNTHETIC FILTER FABRIC IS USED r THE ST]='EL POSTS MUST BE A MAXIMUM DISTANCE OF 6. C3� ISOMETRIC pest _•• NOTE - THE SECTION REVERSES NORTH OF THE PROPOSED BRICOE, ice,. FLOW WILL BE FROM LEFT TO RIGHT. P, I E -rO A� MATCH Lam' AND MATTED. ALL MATTING SHALL BE STRAW UXT14 NET t 2 f} UNLESS SPECIFIED OTl-IERlIA3E ' / , / - Awl C44 a Y " No. 51 STONE OR BETTER _ _ �'� , Grp ;. \L 6 � ({� "crusher run" , marl, abc, etc.) � ~ f = °1R o TYPICAL ROAD SECTION � � r - r _ - - � NOT TO SCALE f -rf `t! ' / "^{e THE DITCHES SHALL. HE GRADED TO MEET EXISTING / � `` I ` - `� � � � / � �t �� ` ��c �A NATURAL QftANND AT THE DISCHARGE POINT At ,� �- j REMOVE ANY VEGETATION AND ROOTS TO A DEPTH OF 8" UT14 THE SLOPE FROM R,IGHT TO LEFT ECiLIAL TO THE EXISTING SLOPE FOR A WIDTH OF 26'. THERE SMALL BE A STRIP OF 3' WIDTH OF NATURAL SOIL WHICH SHALL BE MDISTURIBED, OR P DISTURBED, SOD OR MULCHED, SEEDED WITH THE APPROPRIATE SEEDING SPECIFICATIONS FOR THE SEASON AND MATTED. THE DITCH SHALL BE SODDED OR N"MEDIATELY MULCHED AND SEEDED WITH THE r +f APPROPRIATE SEEDING SPECIFICATIONS FOR THE SEASON r SILT FENCE DETAIL THE � DITCH' STATION SHOWN ON THE PLANS. l _ _ - i� 'J�\ _ 1- se►,;, , i ��/L j - f, ` ,�I I / � 3 � _ 00L_ --- �\ NOT TO SCALE -II/ / 4ry3\ Cr��� // /� / /` /�IJ®100 �. DITCH j _ / ,, j Awl ELF 1 n 'r / / / �� / f i / / ED�E OF ALLIGATOR I' / SHEET_tL4C!!JBRANCH - FROM -_EEb \� DITG-I +3+/�� / I \ ICI{ \ • �''"K :: _l:.:' :: : \ %`C L!� �`' ::mot:::::. : �¢ / Lf/C if� b / �ti!/_ I il \ \ \ \ i . ti \ - \\ tit-_::: r ��� lr Or "�1 _ _ -<Q ...:�?i=• `'� I n'i{ll Al lo i P C ti t � vS / c r \ 1 -I _... _....r:•.:. _.._.. ... .......::: Sri JI t�\Too MOO / j \ 101,233 �q ft: \ \ \ \ / a I \ 2 bs't Sq_ ft. _ _ ::::::::.:: .:: '� - - i / I 2.32 acres- - J a ties :•. !'J�oPO � r a -____ _+ \ `\ �� `\ 2s,3®�,'> I , '- i IBA R► �eAoplum Location \ �� = V f IODbore I _ El = 43.& J igrourd �_ - / _ J / _ \ \ Eia►.. 39�' (sMur) _ I / f �i / ` \ " :=: = _ r / - y Elev. U "/ \ 939 �4{ � ` - � . S' (dw ltd�t,� Q \ :::.: I g$ \ 82 75 aCrr°5 Oa _ \ � 1 � I • \, 1 \\IrIsrL PROPOSEDgOFd{GT10N / \\ l r \ ,, • ♦ ` \ \ \ ` ` `i�L �'� �1�� A1i \ EXIT / ENTRANCEj pest-,- -L .\ TTe I A'i JS 1 `-�100 YEAR FLOOD�`lE ' _ I} m w i \ \ -k, j 1 :_4 @Q�G ~- fe .•. / U' -44 LF or 15" HDPE - _ - / \ -- / / _ _ / / \ j / J kN r STA, a 10485 TEMPORARY SWR IEi T TRAP "a nRPL ATiONS GL49PLIlo aAL CAL_c.XIl ATkM I . ` � •T• T.T• fi• � � GENERAL 1NOTES4 I. TOPOGRAPHIC INFORMATION FROM RR124MICK COUNTY LIDAR INFOFd"iATION_ 2. C.ONTRACTOR TO FIELD VERIFY ALL EXISTING UNDERGROUND UTILITIES BEFORE BEGINNING CONSTRUCTION. 3. TOTAL AREA OF DISTURBANCE IS APPROXIMATELY 432 ACRES. 4. THEM WILL BE NO PERMANENT ROADWAY DITCHES, ONLY TEMPORARY DITCHES FOR THE PURPOSES OF CONTROLLNG THE RUN-OFF FROM THE TEMPORARY GRAVEL ACCESS ROAD_ 5. SILT FENCES WILL CONTROL SHEET FLOW WHERE DITCHES WILL NOT BE CONSTRICTED - EXCEPT - A TEMPORARY DIVERSION DIKE WILL BE CONSTRUCTED TO DIRECT RUN-OFF TO ST04. SEDIMENTATION OPERATION t MAINTENANCE NOTES: 1. ALL EROSION AND SEDIMENT CONTROL PRACTICES WILL BE CHECKED FOR STA5iLITY AND OPERATION FOLLOWING EVERY fa NOFF-PRODUCING RAINFALL BUT IN NO CASE LESS THAN ONCE EVERY WEEK ANY NEEDED REPAIRS WILL BE MADE IMMEDIATELY TO MAINTAIN ALL PRACTICES AS DESIGNED. 2. TEMPORARY CONSTRUCTION ENTRANCE WiLL BE INSPECTED WEEKLY IN ORDER TO KEEP SEDIMENT FROM BEINGS TRANSPORTED OFFSITE. 3. CONTRACTOR SHALL INSPECT AND MAINTAIN ALL SEDIMENT/EROSION CONTROL DEVICES PER THE NORTH CAROLNA EROSION AND SEDIMENT CONTROL PLArNINCs AND DESIGN MANUAL. SEQLENGE OF PRELIMINARY LAND DISTURBANCE 1. PRECONSTRICTION CONFERENCE TO BE HELD PRIOR TO BEGINNINCx 2. DETERMINE AND MARK LIMITS OF PSRELIMINARY DISTURBANCE. 3. INSTALL THE GRAVEL CONSTRUCTION ENTRANCE. 4. CONSTRUCTION OF TEMPORARY EROSION CONTROL FEATURES (INCLUDING ALL SEDIMENT TRAPS). 5. CLEAR AND GRUB AREA OF PRELIMINARY DISTURBANCE: Co. TOPSOIL REMOVAL AND/OR STORAGE IN POSSIDLE BERMS. 1. INSPECT AND MAINTAIN ALL EROSION CONTROL.. DEVICES EVERT" 1 DAYS AND AFTER EACH SIGNIFICANT RAINFALL EVENT (05" OR GREATER). 8. PLACE TEMPORARY °SEEDINCs ON ANY DISTURBED AREAS THAT ARE TO BE LEFT IDLE FOR MORE THAN 15 DAYS. 50' MIN. FOGIANENT D ' " DIVERSION TO DIRECT RUNOFF FROM R/W Mixture "='== _ Seed _ _.._.:_...-..._ _- __=-__==-:=m:.-..-� r::, �-.�::::.�-_�.-�-.-.,:-�-.�::�-�-_���-�-- --------__..__..._.._._.__.........:..:_.-......_....... Specles Rete(No/acre) Plansacola Bahia ass SECTION VIEW Sericea W""Cleza 30 Common Borrra►dagras , 10 German millet 5 DITC14ES ONLY Common Bermudagrass 40-80 (1/2 bA0W a% ft.) Seeding Note L Where a neat appearance Is desired - Omit sericea. 2. Use a common bermudagrass only on isolated sites ai`nr.re it cannot become a post. Bermudagrass may be replaced with 5 b/acre centipedecgIrase. seeding Dates Apr. I - JuN 15 Soil Amendments Apply line and fertilizer according to soil tests or apply 3~ b/acre ground agricultural limestone and WO b/acre I0-10-10 fertilizer. Mulch Appiug 4~ b/acre grain straw or equivalent cover of another suitable mulch Anchor mulch by tacking with asphalt, roving, netting, or by crmpkng with a mulch anchoring tool. A disk with the blades set nearly straight can be used as a mulch and-oring tool. in the ditches, apply 4~ b/acre grain straw, and anchor straw by stapling nettng aver the top Mulch and anchoring can clog other drainage devices. TEMPORARY CONSTRUCTION ENTRANCE N.T.S. Maintenance Inspect seeded areas for fall re and maka necessary r'epalrs and re-seedings within the same season, it possible. FWwtllize the following April with 50 Ib/acre nitrogen. Repeat as growth requires. May be rowed only once a year. Where a neat appearance is desired, omit sericen and crow as often as needed. in the ditches a minimum or 3 wieeM Is required for establishment. Inspect and repair mulch ftmpx ntly. Refertilize the following April with 50 1:,/Acre nitrogen. Tres * Draina a RIn-off 10 QI0 Surface Area Width Lenpith Surface Area la Volume Volume Weir Area Caeff. Peak Flow REQUIRED PROVIDED ,Area REQUIRED PROVIDED L th (acres) C•• (inAT) (cfe) (6q. ft.) (ft.) (ft) ( . fL) (acres) (cu. ft.) (ft.). (cu. Eta (ft-) STsiA OA" 02 120 0.13 36 9 21 243 001 252 2.0 262 4 ST 015 0.16 02 504 om 333 13 49, 1 598 026 S36 3.0 948 4 STr2 2.M 0.2 6.00 251 1031 20 60 1200 035 1260 20 1824 8 ST03 232 02 512 2A65 1155 20 60 1200 021 912 2-0 1824 8 ST'+4 LW 02 630 23S 1041 20 60 1200 0.15 540 20 1824 6 ST5 2Z6 1 02 4.61 1 2.61 1162 20 65 1300 055 MW 2.0 1984 8 sm 033. 02 6146 I 0.43 189 12 32- 3B4 0.10 360 2.0 368 4 Volume required is 3AW cubic reset par acre of disturbed area of land. The run-off coefficient comes from the associated calculations submitted with this plan. 10-yr Intensity is based on the Wilmington IDF where I - 252/30+Tc, from HP_ Malcom, PF_ and associated ditch calculations. Volume calculations assume 2:1 side slopes on all traps. The weir length comes from Table 6r60a, "Design of Spillways", North Carolina Erosion and Sediment Control Planning and Design Manual. Design settled top Compacted soil min. Natura l ground mm'100RARY DIVERSION DIKE (Earthm) NOT TO SCALE max5. fill 2' to 35' --* - fitter fabric 3' Min. CROSS - SECTION VIEW 12" (min.) of N.C. D.O.T. 45 s' or 051 washed stone, t' Min )600 cubic feet per acre of disturbed Overfill &" For gPttliemiant .a ooe Emergent by- ass roll below settled top of dam Natura I ground TEMPORARY SMAMENT TRAM NOT TO SCALE FINAL DESIGN NOT FOR CONSTRUCTION TOR AGENCY REVIEW ONL / 14Y1 MORTi 1414MWE5T R/z`'8� 6 2 „�, 1 ,4- 14M 1 PN NIX AC r4l L \� ASTBROOK I�1TE i 81 1�ALM _k 14 LEL-ANP Y j� T Tj �, 0!(� Mrchl NOT TO SCALE 04 rLE '- -- 8 PROJECT BOUNDARY and COMERS - NOT SURVEYED - - - - - - EXISTINGs MINOR CONTOURS 09 - - - - - -- EXISTNrs MAJOR CONTOURS (101) - - - - - - - - DRAINA[sE AREA DISTURBED AWA POTENTIAL WETLAND -� AREA PROPOSED TEMPORARY ::ram•= •r DRIVE _ DITCH LINE and FLOW DIRECTION SURFACE WATER FLOW ..• ": PROPOSED TEMP. SEDIMENT TRAP 77 PROPOSED TEMP. SEDIMENT TRAP WEIR TD PROPOSED TEMPORARY DIVERSION DIKE SF - PROPOSED SILT FENCE PROPOSED RIP -RAP AREA rhoilj" *a& 41M Sam (k7lof 0% ti lipa vim Ards 00 weirs (11110i i 04 fu doNlow DII.rl.laed Aseb 422 saw & a bpatisoiN arev l MW The disturbed area does not include the bridge section. The 40' contour sh mm on this drawing is not present in the prunewfck County LiDAR information reeeiverd from the county and Is an estimation, drawn between contour 38 and contour 42 by age A ISSUED TO NwEm FOR REVIEW wG 1-27-07 REVS • DESCRIPTION KEV.BY IL DATEREVISiOiVS a SEAL 03o5$s z •,�_ �OI INI� .� CLIENT: ZOV, Inc. P.O. Sox 1 `361 Wilmington, N.C. 28405 (910)392 -9325 -...rn- CAPE FEAR Engineering, Inc. 151 Poole Rd, SufAe 100 BeWfie, NC 28451 TEL (910) 3831044 FAX (910) 3834045 www.capefearengineering.com DRAWN : M SEFFELS PROJECT NUMBER: 655-09 DESIGN : PAL SEFFELS Ch1EC& : K UJTHERAN SCALE : r - KXY APPROVED : L GLMAN DATE : 30 OCT. 07 ALLIGATOR BRIDC� TEMPORARY DRIVEWAY SWEC PROJECT NUMBER SHEET NUMBER 655-09 SWEC r I' +E I 1- .. 1 ','.7 - _ v -- k� ,! 'r .r1' ;f 'li •1!i) •'iS, r�- I'.1 rr y��f Li I } �1 � a{ f ,1 ti ��'I�:ri•. +.',�� ,p n�)1- .�4 •rl:' II '� t .1