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HomeMy WebLinkAbout20140759 Ver 1_Stormwater Info_20140721Hugh J. Gilleece, III & Associates, P.A. 875 Walnut Street, Suite 360 Cary, North Carolina 27511 Consulting Engineers — (919) 469 -I10I Business License C -496 Stormwater Operation and Maintenance Manuals for Wildblood Subdivision Ralph Stephens Road Holly Springs, North Carolina Prepared For Beazer Homes - Raleigh 4509 Creedmoor Road, Suite 200 Raleigh, North Carolina 27612 Prepared by Hugh J. Gilleece, III and Asso gilleece@,bellsouth.net CA RCN � S ���� �. p "0� Z fee SEAL <z 024627° A. Beazer Vaughan Subdivision Stormwater Operation and Maintenance Manuals Table of Contents Wet Pond 1 — Operations and Maintenance Manual (Form 16024) Operations and Maintenance Manual Operations and Maintenance Log Wet Pond 2 — Operations and Maintenance Manual (Form 16024) Operations and Maintenance Manual Operations and Maintenance Log Wet Pond 3 — Operations and Maintenance Manual (Form 16024) Operations and Maintenance Manual Operations and Maintenance Log Level Spreader FES 200 — Operations and Maintenance Manual (Form SWU401) Operations and Maintenance Manual BEAZER VAUGHAN SUBDIVISION. BMP LOCATION MAP �XHBT '1 { --111 1 v Qo CIwIr�Q wlr� , LEVEL WET PONS 1 - NO v� 9 lba l0 d� WET PONE> 2 R f: A n 4--. PONS 3 BEAZER VAUGHAN SUBDIVISION BMP LOCATION MAP IE_XHEi -r 2 HOLLY SPRING3%8. NC WET PON BEAZER VAUGHAN SUBDIVISION BMP LOCATION MAP I BMP 1 HOLLY SPRINCQS, NC Lei Wildwood Subdivision Holly Springs, North Carolina Owner /Financially Responsible Party: Name: Beazer Homes Address : 4509 Creedmoor Rd Suite 200 Raleigh, NC 27612 Contact Name: Contact Name Britt Spivey Contact Address Same as Owner Contact Phone # (919) 277 -2406 Contact Fax # 919 277 -2386 Email Address britt.spivey @beazer.com Prepared Bye Design Engineer: Engineering Firm: Hugh J. Gilleece, III Design Engineer Donald A. Sever, P.E. & Associates, P.A. Design Engineer Same as Firm Design Engineer Phone # (919) 469 -1101 Engineering Firm: 875 Walnut St. Ste. 360 Design Engineer Fax Cary, NC 27511 Design Engineer Email Address Donald. sever@att.net Date Submitted by Design Engineer: Date of DRAFT Approval by Town of Holly Springs: Date of Approval by Town of Holly Springs: 16024 O &M Manual Page 1 of 5 1/5/12 6/2/14 Structural Stormwater Best Management Practice (BMP) Maintenance Acknowledgment Wet Detention Basin #1 I. Monthly or after every runoff producing rainfall, whichever comes first: A. Remove debris from trash rack. B. Check and clear orifice of any obstructions. C. Check pond side slopes; remove trash, repair eroded areas before next rainfall. II. Quarterly A. Inspect the collection system (i.e., catch basin, piping, grassed swales) for proper functioning. Clear accumulated trash from basin grates, and basin bottoms, and check piping for obstructions. B. Check pond inlet pipes for undercutting. Repair if necessary. C. Repair any broken pipes. D. Replace rip rap that is choked with sediment. III. Semi- Annually A. Remove accumulated sediment from bottom of outlet structure. B. Check pond depth at various locations. If depth is reduced to 75% of original design depth, remove sediment to original design depth IV. General A. A natural buffer is encouraged along the banks of the pond where appropriate. Annual mowing can be used to maintain a low buffer. Vegetation along the dam should be mowed on a regular basis to discourage root intrusion. B. Wetland plants are encouraged along pond perimeter, however, invasive species such as cattails must be removed when they cover the entire surface area of pond. C. All components of impoundment system are to be kept in good working order. D. In case the ownership of the Impoundment Transfers, the current owner shall, within thirty (30) days of transfer of ownership, notify the Town of Holly Springs Engineering Department, Stormwater Management Division of such ownership transfer. I, Beazer Homes, hereby acknowledge that I represent the financially responsible party for maintenance of the Structural Stormwater Best Management Practices for this site. I will perform the maintenance as outlined above for this project. Operation and maintenance responsibilities may be transferred to the HOA/OWNER upon completion, contingent upon the Town of Holly Springs approving that all installation, performance measures and documentation are in compliance with the approved stormwater management plan. Signature: Managing Member Date: I, , a Notary Public of the State of , County of , do hereby certify that personally appeared before me this day of, and acknowledge due execution of the foregoing instrument. Witness my hand and official seal, Seal My Commission Expires: 16024 O &M Manual Page 2 of 5 1/5/12 OPERATIONS & MAINTENANCE MANUAL Project Name & Phase: Wildwood Subdivision Information: The wet ponds located in the southeast corner of the project will be constructed and maintained by Beazer Homes, 4509 Creedmoor Rd. Suite 200, Raleigh, NC 27612. Attn: Britt Spivey. Phone (919) 277 -2406 Fax 919 277 -2386 email britt.spiveyCt�beazer.com . Deed Book Page A stormwater surety or another approved instrument will be provided in the amount 35% of actual construction cost. This operations and maintenance agreement may be assigned only upon the following conditions: 1. (list any applicable conditions) Date Constructed: Location: North of road C Receiving Watercourse(s): Bass Lake Watershed_(Neuse River Basin) Contractor: (List Construction Information below) Impoundment & Dam Outlet Structure & Pipe Modified Plunge Pool Material Supplies: (List below) Riser Structure DIP Pond Drain Gate Valve Outlet Pipe & Anti -Seep Collar 16024 O &M Manual Page 3 of 5 1/5/12 Project Name & Phase: Wildwood Subdivision Type of BMP: Wet Detention Pond Type of BMP: This manual established procedures for maintenance and operation of the (insert type of BMP this form shall be created specifically for each BMP). I. Maintenance See attached Operation & Maintenance Manual H. OPERATION See attached Operation & Maintenance Manual A. Record Keeping The Town of Holly Springs shall be provided with written inspection reports as specified in this manual. These reports shall be provided annually within 30 days of the anniversary of receipt of the "Stormwater BMP /O &M Responsibility Transfer" letter (form 416037). A professional engineer shall certify the reports. The Town of Holly Springs _Engineering Department_ shall be notified as soon as any deficiencies in the detention structure are recorded. The Town shall be notified of the proposed methods to bring the structure into conformance and furthermore, the Town shall approve of any proposed work to be completed on any part of the structure prior to any work being started. After work has been completed the Town shall inspect and approve of the work before it shall be considered complete. After the Town approves the work an as -built drawing shall be completed and provided to the Town. Note: Operation of a BMP should include the following: • Annual & Quarterly Inspection Reports — a collection of a written inspection report should be kept on record, Inspection should be conducted at minimum quarterly and certified by a professional engineer annually. • Observations — all observations should be recorded. Where periodic inspections are performed following significant rainfall events, these inspections should be logged on the log forms found in Appendix D of the Town's Design Manual or created specifically for the project. • Maintenance — written records of maintenance and/or repairs should be recorded on the Operation & Maintenance Log Form found in Appendix D of the Town's Design Manual or created specifically for the project. • Other Operation Procedures — the owner should maintain a complete and up -to -date set of plans (as -built drawings) and all changes made to the dam over time should be recorded on the as- builts. Mylar and digital as- builts shall be provided to the Town each time they are updated. B. Sedimentation & Dredging Sedimentation from establishing areas tributary to the BMP may eventually result in the reduction of the storage volume and eventually will have to be removed. The frequency of this sediment removal can be reduced by ensuring that the site areas around the building be stabilized with a vegetative ground cover such that it restrains erosion. This would include a periodic application of fertilizer and other treatments necessary to promote a stable groundcover and minimize sedimentation to the BMP. The maintenance on this BMP requires that (provide design specific clean out information here). For aesthetic purposes it may be desirable to maintain it prior to this point. The removed material should be hauled offsite to a suitable landfill site or mounded somewhere on site and stabilized with a groundcover sufficient to restrain erosion. 16024 O &M Document Page 4 of 5 9.25.09 III. INSPECTION, OPERATION & MAINTENANCE LOGS (attach a blank copy of the applicable O&M log for each BMP) (attach 8 112x 11 Location Map) (attach 8 112 x 11 copy of Recorded Plat(s)) (attach the Stormwater Management Plan, including form #16012 and As- builts) (attach Engineer Certifications for construction of each BMP) 16024 O &M Document Page 5 of 5 9.25.09 OPERATIONS & MAINTENANCE MANUAL (Beazer Vaughan Subdivision): Wet Detention Pond #1 This manual established procedures for maintenance and operation of the Beazer Vaughan Subdivision wet detention pond # 1. Maintenance of Embankments A. Vegetation The embankment has a ground cover of fescue, which if properly maintained will prevent erosion of the embankment and provide an easy surface for inspection. The grass will be most difficult to obtain in the area subject to water level fluctuation below the top of the riser. Grass should be fertilized every October and April. ♦ Re- Seeding — periodically re- seeding may be required to establish grass on areas where seek did not take or has been destroyed. Before seeding, fertilizer (12- 12 -12) should be applied at a minimum rate of 12 to 15 pounds per 1,000 SF. The seed should be evenly sewn at a rate of three pounds per 1,000 SF. The seed should be covered with soil to the depth of approximately' / ". Immediately following the planting, the area should be mulched with straw. ♦ Trees & Shrubs — trees, shrubs, and other landscape vegetation should be permitted only as shown on the approved planting plan. ♦ Mowing — grass mowing, brush cuffing and removal of weed vegetation will be necessary for the proper maintenance of the embankment. All embankment slopes and vegetation of spillways should be mowed when the grass exceeds 8" in height. Acceptable methods include the use of weed whips or power brush cutters and mowers. B. Erosion Erosion occurs when the water concentrates causing failure of the vegetation or when vegetation dies and sets up the environment for rill erosion and eventually gullies from the stormwater. runoff. The dam should be inspected for these areas. Proper care of vegetative areas that develop erosion is required to prevent more serious damage to the embankment. Rills and gullies should be filled with suitable soil compacted and then seeded. Methods described in Section I -A, on vegetation, should be used to properly establish the grass surface. Where eroded areas are detected, the cause of the erosion should be addressed to prevent a continued maintenance problem. Frequently problems result from the concentration of runoff to one point of the embankment crest instead of a uniform distribution of runoff. This can be corrected by reshaping the crest to more evenly distribute the runoff to areas, which are not experiencing erosion problems. The top of the dam should not be allowed to be used for pedestrian or bicycle traffic. ♦ Abutment Areas -- the abutment is the line formed where the embankment fill comes into contact with the existing slope. Runoff from rainfall concentrates in these gutter areas and can reach erosive velocities because of the steep slopes. If a normal stand of grass cannot be maintained on the abutments, additional measures may be needed such as jute matting to provide for the establishment of a good ground cover. ♦ Upstream Embankment Slope — Erosion problems can develop on the upstream face of the dam due to the fluctuation of water level in the pond. This is a result of a combination of wave actions and ground saturation, which occurs from the elevated water levels. The erosion generally occurs as the water level falls and the saturated ground becomes subjected to the wave action. If erosion becomes a problem, it. may necessitate the installation of a stone armoring along the zone subject to fluctuating water level. This would consist of 18" of NCDOT Class B stone for erosion control underlain with Mirifi 140 geotextile fabric. It should be centered at the point of the erosion problem and covering an area 2' above and below the approximate center of the eroded area. C. Seepage o Detection — due to the fact that the "permanent" impoundment level is only 5' deep, and the road embankment is immediately downstream and continuous with the dam embankment, seepage should not be expected on the downstream slope of the embankment. However, a cursory inspection of the road embankment should be made for completeness of the inspection. Seepage may vary in appearance from a soft wet area to a flowing spring. It may show up first as only an area where the vegetation is more lush and darker green. Cattails, reeds, mosses and other marsh vegetation often become established in a seepage area. The downstream abutment areas where the embankment fill and natural ground interface are very common locations for seepage. Also the contact between the embankment and the spillway conduit is a very common location which is generally attributed to poor compaction around the conduit. Due to the way in which conduits are put in, this is generally most evident on the underside of the conduit. Slides may result from excessively saturated embankment slopes. The natural foundation area immediately downstream of the dam abutment should also be inspected to ensure that "piping" is not occurring underneath the embankment. "Piping" may appear as a "boil" evident as spring carries soil. The soil usually deposits around the boil area and is evident by the sedimentary deposits accompanying it. Seepage can also occur into the spillway conduit through cracks in the pipe or improperly sealed joints. These can be seen by observing the conduit when the water level is high. The movement of the water itself is not dangerous, but if soil particles are being carried with it, then it can create a shortcut for the piping of soil. This might show up on the upstream face of the embankment roughly along the line of the conduit itself. D. Cracks, Slides, Sloughing, and Settlement ♦ Cracks — the entire embankment should be inspected for cracks. Short, isolated cracks are usually not significant, but larger cracks (wider than '/ "), well defined cracks indicate a serious problem. There are two types of cracks: transverse and longitudinal. Traverse cracks appear crossing the embankment and indicated difference of settlement within the embankment. these cracks provide avenues for seepage and piping could develop. Longitudinal cracks run parallel to the embankment and may signal the early stages of a slide. In recently built structures, these cracks may be indicative of poor compaction or poor foundation preparation resulting in consolidation after construction. ♦ Slides — Slides and slumps are serious threats to the safety of an embankment. Slides can be detected easily unless obscured by vegetation. Arch shaped cracks are indications that slides are slipping or beginning to slip. These cracks soon develop into large scarps in the slope at the top of the slide. e Settlement — settlement occurs both during construction and after the embankment has been completed and places in service. To a certain degree this is normal and should be experienced. It is usually the most pronounced at the location of maximum foundation depth or embankment height. Excessive settlement will reduce the free board (difference in elevation between the water surface and the top of the dam). Any area of excessive settlement should be restored to original elevation and condition to reduce the risk of overtopping. A relatively large amount of settlement (more than 6 ") within a small area could indicate serious problems in the foundation or perhaps the lower part of the embankment. Settlement accompanied by cracking often precedes failure. ♦ What to do if seepage, cracks, slides or settlement are detected: If any of the above items are detected there may be signs of significant problems, which could lead, to the failure of the structure. A geotechnicai or civil engineer should be consulted regarding the origin of these problems and for the assessment of the appropriate solutions for correcting them. If the professional is not immediately able to inspect the dam, then the bottom drain should be opened and the water level lowered to remove the risk of failure until a professional can observe these problems. E. Rodent Control Generally in this urban environment, rodents are not a problem. Rodents such as ground hogs, muskrats, and beavers are attracted to dams and reservoirs and can be quite dangerous to structural integrity and proper performance of the embankment and spillway. Groundhog and muskrats thrive on burrowing in the manmade earth embankments, which become pathways for seepage. In the event that burrows are detected within the dam, then the rodents should be dealt with by removal. II. MAINTENANCE OF SPILLWAYS & CONTROL STRUCTURES A. Inspection of Spillway Conduits Conduits should be inspected thoroughly once a year. Conduits should be visually inspected by actually entering the conduit a sufficient distance between the riser structure and the outlet to check all the joints. Because the outlet works tie into the street storm sewer system, catch basins and pipes. Conduit should be inspected for proper alignment (sagging), elongation and displacement at joints, cracks, leaks, surface water, surface wear, loss of protective coating, corrosion and blocking. Problems with conduits most often occurs at joints and special attention should be given to them during inspection. Joints should be checked for gaps caused by elongation or settlement and loss of joint filler material. Open joints can permit erosion of the embankment material and possibly the piping of soil material through the joints. Catch basin should be checked for signs that water is seeping along the exterior surface of the pipe where it enters the catch basin. A depression in the soil surface over the pipe may be signs that soil is being removed from around the pipe. ♦ What to do if problems are detected with the spillway: Retain the assistance of a civil engineer or geotechnical engineer qualified in the design of embankments to perform an inspection of the dam. If in doubt, lower the water surface elevation of the pond until such time as an inspection can be performed by a qualified professional. B. Trashracks on Pipe Spillways The spillway riser and rip -rap weir for this dam is the only spillway structures. The intake structure has been fitted with a trashrack to prevent debris from entering the spillway structure. Most of the runoff entering the pond comes in through grated inlets, which have essentially provided filtration of the runoff and should limit the size of the debris that enters the basin to floating debris which will most likely pass through the trashrack. The opening between the trashrack and riser is smaller than the opening of the outlet pipe. The intent is that any debris, which passes through the trashrack, will be easily passed by the pipe outlet. Maintenance should include periodically checking the rack for rusted or broken sections and repairing as needed. The trashrack should be checked frequently during and after storm events to ensure that it is properly functioning and to remove accumulated debris. III. OPERATION A. Lake Drains Lake drains should always be operable so that the pool level can be drawn down in case of an emergency or for repairs or maintenance. Lake drain valves or gates that have not been operated for a long time present a special problem. Generally, when draining the pond, it should be drained slowly. Open the drain until a good flow of water is present but not a torrent, so that the water level can be drained over a period of 48 hours or more. Rapidly lowering the water level in the pond can cause permanent damage to the embankment and must be avoided. The gate valve controlling the lake drain should be operated from fully closed to fully opened position at least twice a year. THE TOVM OF Dolly Springs NORTH C A R O L I N A Stormwater BMP Operation & Maintenance Log Wet Detention Basin TOWN OF HOLLY SPRINGS ENGINEERING DEPARTMENT Project Information & BMP Identification Project Name: Beazer Vaughan Subdivision TOHS Project Number: 13 -DO -02 Project Location: Ralph Stephens Road PIN Number: 0658133419/0658034571 Property Owner: Beazer Homes - Raleigh BMP Location: Northwest corner of project BMP Element Operation Inspection Maintenance Inspection Date: Maintenance Required? Maintenance Completed? By: ❑ Yes ❑ Yes Type of Inspection: Quarterly or Annual ❑ No ❑ No Last Rainfall Date: Description: Description: Last Rainfall Amount: Maintenance Required? Maintenance Completed? Today's Weather: ❑ Yes ❑ Yes Photo Attached & Name: ❑ No ❑ Description: BMP Element Status Maintenance Completed Entire BMP Maintenance Required? Maintenance Completed? ❑ Yes ❑ Yes ❑ No ❑ No Description: Description: Drainage Area & Maintenance Required? Maintenance Completed? Perimeter of the BMP ❑ Yes ❑ Yes No No Description: Description: Inlet Device: pipe orswale Maintenance Required? Maintenance Completed? ❑ Yes ❑ Yes ❑ No ❑ No Description: Description: Forebay Maintenance Required? Maintenance Completed? ❑ Yes ❑ Yes ❑ No ❑ No Description: Description: Vegetated Shelf Maintenance Required? Maintenance Completed? ❑ Yes ❑ Yes ❑ No ❑ No Description: Description: 16015 Wet Deterntion Basin O &M 4.1.08 Page 1 of 3 THE TOWN OF AC Molly springs NORTH CAROLINA Stormwater BMP Operation & Maintenance Log Wet Detention Basin TOWN OF HOLLY SPRINGS ENGINEERING DEPARTMENT Aquatic Environment Maintenance Required? Maintenance Completed? ❑ Yes ❑ Yes ❑No F-1 No Description: Description: Main Treatment Area Maintenance Required? Maintenance Completed? ❑ Yes ❑ Yes ❑No ❑No Description: Description: Embankment Maintenance Required? Maintenance Completed? ❑ Yes ❑ Yes ❑ No ❑ No Description: Description: Outlet Device Maintenance Required? Maintenance Completed? ❑ Yes ❑ Yes F-1 No ❑No Description: Description: Receiving Water Maintenance Required? Maintenance Completed? ❑ Yes ❑ Yes ❑No ❑No Description: Description: General Comments, Sketches & Field Measurements (attach if necessary): Include Date & Initials 16015 Wet Deterntion Basin O &M 4.1.08 Page 2 of 3 THE TOWN OF Stormwater BMP Operation & Maintenance Log ri Wet Detention Basin .-. Sprinngs gs NORTH CAROLINA TOWN OF HOLLY SPRINGS ENGINEERING DEPARTMENT Annual Engineer's Certification of Stormwater BMP Operation & Maintenance Note: this section is not required to be filled out for quarterly inspections I a Licensed Professional Engineer in the State of North Carolina, Print Name do hereby certify that the Stormwater BMP Wet Pond Type Constructed as a part of Beazer Vaughan Tract , project located at Name of Project the southeast side of Street C, north of the Street C/ D intersection. Size /lot/general description has been maintained in substantial accordance with the approved plans and specifications, dated: Date This is certification is based on my field observation during the periodic & annual operation and maintenance inspections and other methods as follows (if applicable): (Seal) Date: 16015 Wet Deterntion Basin O &M 4.1.08 Page 3 of 3 PE #: Wet Pond 2 EEAZER VAUGHAN SUBDIVISION HOLLY SPRINQS, NC BMP LOCATION MAP I'IC�]�I►C� 1; MAINTENANCE MANUAL Wildwood Subdivision Holly Springs, North Carolina Owner /Financially Responsible Party: Name: Beazer Homes Address : 4509 Creedmoor Rd Suite 200 Raleigh, NC 27612 Contact Name: Contact Name Britt Spivey Contact Address Same as Owner Contact Phone # (919) 277 -2406 Contact Fax # 919 277 -2386 Email Address britt.spivey @beazer.com Prepared By: __ Design Engineer: Engineering Firm: Hugh J. Gilleece, III Design Engineer Donald A. Sever, P.E. & Associates, P.A. Design Engineer Same as Firm Design Engineer Phone # (919) 469 -1101 Engineering Firm: 875 Walnut St. Ste. 360 Design Engineer Fax Cary, NC 27511 Design Engineer Email Address Donald. sever @att.net Date Submitted by Design Engineer: 6/2/14 Date of DRAFT Approval by Town of Holly Springs: Date of Approval by Town of Holly Springs: 16024 O &M Manual Page 1 of 5 1/5/12 Structural Stormwater Best Management Practice (BMP) Maintenance Acknowledgment Wet Detention Basin #2 I. Monthly or after every runoff producing rainfall, whichever comes first: A. Remove debris from trash rack. B. Check and clear orifice of any obstructions. C. Check pond side slopes; remove trash, repair eroded areas before next rainfall. II. Quarterly A. Inspect the collection system (i.e., catch basin, piping, grassed swales) for proper functioning. Clear accumulated trash from basin grates, and basin bottoms, and check piping for obstructions. B. Check pond inlet pipes for undercutting. Repair if necessary. C. Repair any broken pipes. D. Replace rip rap that is choked with sediment. III. Semi- Annually A. Remove accumulated sediment from bottom of outlet structure. B. Check pond depth at various locations. If depth is reduced to 75% of original design depth, remove sediment to original design depth IV. General A. A natural buffer is encouraged along the banks of the pond where appropriate. Annual mowing can be used to maintain a low buffer. Vegetation along the dam should be mowed on a regular basis to discourage root intrusion. B. Wetland plants are encouraged along pond perimeter, however, invasive species such as cattails must be removed when they cover the entire surface area of pond. C. All components of impoundment system are to be kept in good working order. D. In case the ownership of the Impoundment Transfers, the current owner shall, within thirty (30) days of transfer of ownership, notify the Town of Holly Springs Engineering Department, Stormwater Management Division of such ownership transfer. I, Beazer Homes, hereby acknowledge that I represent the financially responsible party for maintenance of the Structural Stormwater Best Management Practices for this site. I will perform the maintenance as outlined above for this project. Operation and maintenance responsibilities may be transferred to the HOA/OWNER upon completion, contingent upon the Town of Holly Springs approving that all installation, performance measures and documentation are in compliance with the approved stormwater management plan. Signature: Managing Member Date: I, , a Notary Public of the State of , County of , do hereby certify that personally appeared before me this day of, and acknowledge due execution of the foregoing instrument. Witness my hand and official seal, Seal My Commission Expires: 16024 O &M Manual Page 2 of 5 1/5/12 OPERATIONS & MAINTENANCE MANUAL Project Name & Phase: Wildwood Subdivision Information: The wet ponds located in the southeast corner of the project will be constructed and maintained by Beazer Homes, 4509 Creedmoor Rd. Suite 200, Raleigh, NC 27612. Attn: Britt Spivey. Phone (919) 277 -2406 Fax 919 277 -2386 email britt.spiveygbeazer.com . Deed Book Page A stormwater surety or another approved instrument will be provided in the amount 35% of actual construction cost. This operations and maintenance agreement may be assigned only upon the following conditions: 1. (list any applicable conditions) Date Constructed: Location: South of road C Receiving Watercourse(s):_ _ _ Bass Lake Watershed (Meuse River Basin) Contractor: (List Construction Information below) Impoundment & Dam Outlet Structure & Pipe Modified Plunge Pool Material Supplies: (List below) Riser Structure DIP Pond Drain Gate Valve Outlet Pipe & Anti -Seep Collar 16024 O &M Manual Page 3 of 5 1/5/12 Project Name & Phase: Wildwood Subdivision Type of BMP: Wet Detention Pond Type of BMP: This manual established procedures for maintenance and operation of the (insert type of BMP this form shall be created specifically for each BMP). I. Maintenance See attached Operation & Maintenance Manual H. OPERATION See attached Operation & Maintenance Manual A. Record Keeping The Town of Holly Springs shall be provided with written inspection reports as specified in this manual. These reports shall be provided annually within 30 days of the anniversary of receipt of the "Stormwater BMP /O &M Responsibility Transfer" letter (form #16037). A professional engineer shall certify the reports. The Town of Holly Springs Engineering Department shall be notified as soon as any deficiencies in the detention structure are recorded. The Town shall be notified of the proposed methods to bring the structure into conformance and furthermore, the Town shall approve of any proposed work to be completed on any part of the structure prior to any work being started. After work has been completed the Town shall inspect and approve of the work before it shall be considered complete. After the Town approves the work an as -built drawing shall be completed and provided to the Town. Note: Operation of a BMP should include the following: • Annual & Quarterly Inspection Reports — a collection of a written inspection report should be kept on record, Inspection should be conducted at minimum quarterly and certified by a professional engineer annually. • Observations — all observations should be recorded. Where periodic inspections are performed following significant rainfall events, these inspections should be logged on the log forms found in Appendix D of the Town's Design Manual or created specifically for the project. • Maintenance — written records of maintenance and/or repairs should be recorded on the Operation & Maintenance Log Form found in Appendix D of the Town's Design Manual or created specifically for the project. • Other Operation Procedures — the owner should maintain a complete and up -to -date set of plans (as -built drawings) and all changes made to the dam over time should be recorded on the as- builts. Mylar and digital as- builts shall be provided to the Town each time they are updated. B. Sedimentation & Dredging Sedimentation from establishing areas tributary to the BMP may eventually result in the reduction of the storage volume and eventually will have to be removed. The frequency of this sediment removal can be reduced by ensuring that the site areas around the building be stabilized with a vegetative ground cover such that it restrains erosion. This would include a periodic application of fertilizer and other treatments necessary to promote a stable groundcover and minimize sedimentation to the BMP. The maintenance on this BMP requires that (provide design specific clean out information here). For aesthetic purposes it may be desirable to maintain it prior to this point. The removed material should be hauled offsite to a suitable landfill site or mounded somewhere on site and stabilized with a groundcover sufficient to restrain erosion. 16024 O &M Document Page 4 of 5 9.25.09 III. INSPECTION, OPERATION & MAINTENANCE LOGS (attach a blank copy of the applicable O&M log for each BMP) (attach 8 Y2 x 11 Location Map) (attach 8 Y2 x I1 copy of Recorded Plat(s)) (attach the Stormwater Management Plan, including form #16012 and As- builts) (attach Engineer Certifications for construction of each BMP) 16024 O &M Document Page 5 of 5 9.25.09 OPERATIONS & MAINTENANCE MANUAL (Beazer Vaughan Subdivision): Wet Detention Pond #2 This manual established procedures for maintenance and operation of the Beazer Vaughan Subdivision wet detention pond # 2. Maintenance of Embankments A. Vegetation The embankment has a ground cover of fescue, which if properly maintained will prevent erosion of the embankment and provide an easy surface for inspection. The grass will be most difficult to obtain in the area subject to water level fluctuation below the top of the riser. Grass should be fertilized every October and April. ♦ Re- Seeding — periodically re- seeding may be required to establish grass on areas where seek did not take or has been destroyed. Before seeding, fertilizer (12- 12 -12) should be applied at a minimum rate of 12 to 15 pounds per 1,000 SF. The seed should be evenly sewn at a rate of three pounds per 1,000 SF. The seed should be covered with soil to the depth of approximately' / ". Immediately following the planting, the area should be mulched with straw. ♦ Trees & Shrubs — trees, shrubs, and other landscape vegetation should be permitted only as shown on the approved planting plan. ♦ Mowing — grass mowing, brush cutting and removal of weed vegetation will be necessary for the proper maintenance of the embankment. All embankment slopes and vegetation of spillways should be mowed when the grass exceeds 8" in height. Acceptable methods include the use of weed whips or power brush cutters and mowers. B. Erosion Erosion occurs when the water concentrates causing failure of the vegetation or when vegetation dies and sets up the environment for rill erosion and eventually gullies from the stormwater runoff. The dam should be inspected for these areas. Proper care of vegetative areas that develop erosion is required to prevent more serious damage to the embankment. Rills and gullies should be filled with suitable soil compacted and then seeded. Methods described in Section I -A, on vegetation, should be used to properly establish the grass surface. Where eroded areas are detected, the cause of the erosion should be addressed to prevent a continued maintenance problem. Frequently problems result from the concentration of runoff to one point of the embankment crest instead of a uniform distribution of runoff. This can be corrected by reshaping the crest to more evenly distribute the runoff to areas, which are not experiencing erosion problems. The top of the dam should not be allowed to be used for pedestrian or bicycle traffic. ♦ Abutment Areas -- the abutment is the line formed where the embankment fill comes into contact with the existing slope. Runoff from rainfall concentrates in these gutter areas and can reach erosive velocities because of the steep slopes. If a normal stand of grass cannot be maintained on the abutments, additional measures may be needed such as jute matting to provide for the establishment of a good ground cover. o Upstream Embankment Slope — Erosion problems can develop on the upstream face of the dam due to the fluctuation of water level in the pond. This is a result of a combination of wave actions and ground saturation, which occurs from the elevated water levels. The erosion generally occurs as the water level falls and the saturated ground becomes subjected to the wave action. If erosion becomes a problem, it may necessitate the installation of a stone armoring along the zone subject to fluctuating water level. This would consist of 18" of NCDOT Class B stone for erosion control underlain with Mirifi 140 geotextile fabric. It should be centered at the point of the erosion problem and covering an area 2' above and below the approximate center of the eroded area. C. Seepage e Detection — due to the fact that the "permanent" impoundment level is only 5' deep, and the road embankment is immediately downstream and continuous with the dam embankment, seepage should not be expected on the downstream slope of the embankment. However, a cursory inspection of the road embankment should be made for completeness of the inspection. Seepage may vary in appearance from a soft wet area to a flowing spring. It may show up first as only an area where the vegetation is more lush and darker green. Cattails, reeds, mosses and other marsh vegetation often become established in a seepage area. The downstream abutment areas where the embankment fill and natural ground interface are very common locations for seepage. Also the contact between the embankment and the spillway conduit is a very common location which is generally attributed to poor compaction around the conduit. Due to the way in which conduits are put in, this is generally most evident on the underside of the conduit. Slides may result from excessively saturated embankment slopes. The natural foundation area immediately downstream of the dam abutment should also be inspected to ensure that "piping" is not occurring underneath the embankment. "Piping" may appear as a "boil" evident as spring carries soil. The soil usually deposits around the boil area and is evident by the sedimentary deposits accompanying it. Seepage can also occur into the spillway conduit through cracks in the pipe or improperly sealed joints. These can be seen by observing the conduit when the water level is high. The movement of the water itself is not dangerous, but if soil particles are being carried with it, then it can create a shortcut for the piping of soil. This might show up on the upstream face of the embankment roughly along the line of the conduit itself. D. Cracks, Slides, Sloughing, and Settlement ♦ Cracks — the entire embankment should be inspected for cracks. Short, isolated cracks are usually not significant, but larger cracks (wider than '/ "), well defined cracks indicate a serious problem. There are two types of cracks: transverse and longitudinal. Traverse cracks appear crossing the embankment and indicated difference of settlement within the embankment. these cracks provide avenues for seepage and piping could develop. Longitudinal cracks run parallel to the embankment and may signal the early stages of a slide. In recently built structures, these cracks may be indicative of poor compaction or poor foundation preparation resulting in consolidation after construction. ♦ Slides — Slides and slumps are serious threats to the safety of an embankment. Slides can be detected easily unless obscured by vegetation. Arch shaped cracks are indications that slides are slipping or beginning to slip. These cracks soon develop into large scarps in the slope at the top of the slide. ♦ Settlement — settlement occurs both during construction and after the embankment has been completed and places in service. To a certain degree this is normal and should be experienced. It is usually the most pronounced at the location of maximum foundation depth or embankment height. Excessive settlement will reduce the free board (difference in elevation between the water surface and the top of the dam). Any area of excessive settlement should be restored to original elevation and condition to reduce the risk of overtopping. A relatively large amount of settlement (more than 6 ") within a small area could indicate serious problems in the foundation or perhaps the lower part of the embankment. Settlement accompanied by cracking often precedes failure. ♦ What to do if seepage, cracks, slides or settlement are detected: If any of the above items are detected there may be signs of significant problems, which could lead, to the failure of the structure. A geotechnical or civil engineer should be consulted regarding the origin of these problems and for the assessment of the appropriate solutions for correcting them. If the professional is not immediately able to inspect the dam, then the bottom drain should be opened and the water level lowered to remove the risk of failure until a professional can observe these problems. E. Rodent Control Generally in this urban environment, rodents are not a problem. Rodents such as ground hogs, muskrats, and beavers are attracted to dams and reservoirs and can be quite dangerous to structural integrity and proper performance of the embankment and spillway. Groundhog and muskrats thrive on burrowing in the manmade earth embankments, which become pathways for seepage. In the event that burrows are detected within the dam, then the rodents should be dealt with by removal. II. MAINTENANCE OF SPILLWAYS & CONTROL STRUCTURES A. Inspection of Spillway Conduits Conduits should be inspected thoroughly once a year. Conduits should be visually inspected by actually entering the conduit a sufficient distance between the riser structure and the outlet to check all the joints. Because the outlet works tie into the street storm sewer system, catch basins and pipes. Conduit should be inspected for proper alignment (sagging), elongation and displacement at joints, cracks, leaks, surface water, surface wear, loss of protective coating, corrosion and blocking. Problems with conduits most often occurs at joints and special attention should be given to them during inspection. Joints should be checked for gaps caused by elongation or settlement and loss of joint filler material. Open joints can permit erosion of the embankment material and possibly the piping of soil material through the joints. Catch basin should be checked for signs that water is seeping along the exterior surface of the pipe where it enters the catch basin. A depression in the soil surface over the pipe may be signs that soil is being removed from around the pipe. ♦ What to do if problems are detected with the spillway: Retain the assistance of a civil engineer or geotechnical engineer qualified in the design of embankments to perform an inspection of the dam. If in doubt, lower the water surface elevation of the pond until such time as an inspection can be performed by a qualified professional. B. Trashracks on Pipe Spillways The spillway riser and rip -rap weir for this dam is the only spillway structures. The intake structure has been fitted with a trashrack to prevent debris from entering the spillway structure. Most of the runoff entering the pond comes in through grated inlets, which have essentially provided filtration of the runoff and should limit the size of the debris that enters the basin to floating debris which will most likely pass through the trashrack. The opening between the trashrack and riser is smaller than the opening of the outlet pipe. The intent is that any debris, which passes through the trashrack, will be easily passed by the pipe outlet. Maintenance should include periodically checking the rack for rusted or broken sections and repairing as needed. The trashrack should be checked frequently during and after storm events to ensure that it is properly functioning and to remove accumulated debris. 111�QTAS-JAV Q-LI1 A. Lake Drains Lake drains should always be operable so that the pool level can be drawn down in case of an emergency or for repairs or maintenance. Lake drain valves or gates that have not been operated for a long time present a special problem. Generally, when draining the pond, it should be drained slowly. Open the drain until a good flow of water is present but not a torrent, so that the water level can be drained over a period of 48 hours or more. Rapidly lowering the water level in the pond can cause permanent damage to the embankment and must be avoided. The gate valve controlling the lake drain should be operated from fully closed to fully opened position at least twice a year. THE TOWN OF Dolly Springs NORTH C A R O L I N A Stormwater BMP Operation & Maintenance Log Wet Detention Basin TOWN OF HOLLY SPRINGS ENGINEERING DEPARTMENT Project Information & BMP Identification Project Name: Beazer Vaughan Subdivision TOHS Project Number: 13 -DO -02 Project Location: Ralph Stephens Road PIN Number: 0658133419/0658034571 Property Owner: Beazer Homes - Raleigh BMP Location: South of Street D BMP Element Operation Inspection Maintenance Inspection Date: Maintenance Required? Maintenance Completed? By: ❑ Yes ❑ Yes Type of Inspection: Quarterly or Annual ❑ No ❑ No Last Rainfall Date: Description: Description: Last Rainfall Amount: Maintenance Required? Maintenance Completed? Today's Weather: ❑ Yes ❑ Yes Photo Attached & Name: ❑ ❑ No ❑ Description: BMP Element Status Maintenance Completed Entire BMP Maintenance Required? Maintenance Completed? ❑ Yes ❑ Yes ❑ No ❑ No Description: Description: Drainage Area & Maintenance Required? Maintenance Completed? Perimeter of the BMP ❑ Yes ❑ Yes ❑ No ❑ No Description: Description: Inlet Device: pipe orswale Maintenance Required? Maintenance Completed? ❑ Yes ❑ Yes ❑ No ❑ No Description: Description: Forebay Maintenance Required? Maintenance Completed? ❑ Yes ❑ Yes ❑ No ❑ No Description: Description: Vegetated Shelf Maintenance Required? Maintenance Completed? ❑ Yes ❑ Yes ❑ No ❑ No Description: Description: 16015 Wet Deterntion Basin O &M 4.1.08 Page 1 of 3 THE TOWN OF Holly Springs NORTH CAROLINA Stormwater BMP Operation & Maintenance Log Wet Detention Basin TOWN OF HOLLY SPRINGS ENGINEERING DEPARTMENT Aquatic Environment Maintenance Required? Maintenance Completed? ❑ Yes ❑ Yes ❑ No ❑ No Description: Description: Main Treatment Area Maintenance Required? Maintenance Completed? ❑ Yes ❑ Yes ❑ No ❑ No Description: Description: Embankment Maintenance Required? Maintenance Completed? ❑ Yes ❑ Yes ❑ No ❑ No Description: Description: Outlet Device Maintenance Required? Maintenance Completed? ❑ Yes ❑ Yes ❑ No ❑ No Description: Description: Receiving Water Maintenance Required? Maintenance Completed? ❑ Yes ❑ Yes ❑ No ❑ No Description: Description: General Comments, Sketches & Field Measurements (attach if necessary): Include Date & Initials 16015 Wet Deterntion Basin O &M 4.1.08 Page 2 of 3 THE TOWN OF Stormwater BMP Operation & Maintenance Log Molly Springs Wet Detention Basin NORTH CAROLINA TOWN OF HOLLY SPRINGS ENGINEERING DEPARTMENT Annual Engineer's Certification of Stormwater BMP Operation & Maintenance Note: this section is not required to be filled out for quarterly inspections a Licensed Professional Engineer in the State of North Carolina, Print Name do hereby certify that the Stormwater BMP Wet Pond Type Constructed as a part of Beazer Vaughan Tract , project located at Name of Project the southeast side of Street D. Size /lot/general description has been maintained in substantial accordance with the approved plans and specifications, dated: uate This is certification is based on my field observation during the periodic & annual operation and maintenance inspections and other methods as follows (if applicable): (Seal Date: 16015 Wet Deterntion Basin O &M 4.1.08 Page 3 of 3 SM Wet Pond 3 1►1muluc, BEAZER VAUGHAN SUBDIVISION BMP LOCATION MAP BMP 3 HOLLY SPRINC3S, NC 11711,11 ,' / 1 MAINTENANCE MANUAL. Wildwood Subdivision Holly Springs, North Carolina Owner /Financially Responsible Party: Name: Beazer Homes Address : 4509 Creedmoor Rd Suite 200 Raleigh, NC 27612 Prepared By: Engineering Firm: Hugh J. Gilleece, III & Associates, P.A. Engineering Firm: 875 Walnut St. Ste. 360 Cary, NC 27511 Contact Name: Contact Name Britt Spivey Contact Address Same as Owner Contact Phone # (919) 277 -2406 Contact Fax # 919 277 -2386 Email Address britt.spivey @beazer.com Design Engineer: Design Engineer Donald A. Sever, P.E. Design Engineer Same as Firm Design Engineer Phone # (919) 469 -1101 Design Engineer Fax Design Engineer Email Address Donald. sever @att.net Date Submitted by Design Engineer: Date of DRAFT Approval by Town of Holly Springs: Date of Approval by Town of Holly Springs: 16024 O &M Manual Page 1 of 5 1/5/12 6/2/14 Structural Stormwater Best Management Practice (BMP) Maintenance Acknowledgment Wet Detention Basin #3 I. Monthly or after every runoff producing rainfall, whichever comes first: A. Remove debris from trash rack. B. Check and clear orifice of any obstructions. C. Check pond side slopes; remove trash, repair eroded areas before next rainfall. II. Quarterly A. Inspect the collection system (i.e., catch basin, piping, grassed swales) for proper functioning. Clear accumulated trash from basin grates, and basin bottoms, and check piping for obstructions. B. Check pond inlet pipes for undercutting. Repair if necessary. C. Repair any broken pipes. D. Replace rip rap that is choked with sediment. III. Semi- Annually A. Remove accumulated sediment from bottom of outlet structure. B. Check pond depth at various locations. If depth is reduced to 75% of original design depth, remove sediment to original design depth IV. General A. A natural buffer is encouraged along the banks of the pond where appropriate. Annual mowing can be used to maintain a low buffer. Vegetation along the dam should be mowed on a regular basis to discourage root intrusion. B. Wetland plants are encouraged along pond perimeter, however, invasive species such as cattails must be removed when they cover the entire surface area of pond. C. All components of impoundment system are to be kept in good working order. D. In case the ownership of the Impoundment Transfers, the current owner shall, within thirty (30) days of transfer of ownership, notify the Town of Holly Springs Engineering Department, Stormwater Management Division of such ownership transfer. I, Beazer Homes, hereby acknowledge that I represent the financially responsible party for maintenance of the Structural Stormwater Best Management Practices for this site. I will perform the maintenance as outlined above for this project. Operation and maintenance responsibilities may be transferred to the HOA/OWNER upon completion, contingent upon the Town of Holly Springs approving that all installation, performance measures and documentation are in compliance with the approved stormwater management plan. Signature: Managing Member Date: I, , a Notary Public of the State of , County of , do hereby certify that personally appeared before me this day of, and acknowledge due execution of the foregoing instrument. Witness my hand and official seal, Seal My Commission Expires: 16024 O &M Manual Page 2 of 5 1/5/12 OPERATIONS & MAINTENANCE MANUAL Project Name & Phase: Wildwood Subdivision Information: The wet ponds located in the southeast corner of the project will be constructed and maintained by Beazer Homes, 4509 Creedmoor Rd. Suite 200, Raleigh, NC 27612. Attn: Britt Spivey. Phone (919) 277 -2406 Fax 919 277 -2386 email britt.spiveyLbbeazer.coln . Deed Book Page A stormwater surety or another approved instrument will be provided in the amount 35% of actual construction cost. This operations and maintenance agreement may be assigned only upon the following conditions: 1. (list any applicable conditions) Date Constructed: Location: Near Pumping Station off Road A Receiving Watercourse(s): _ _ Bass Lake Watershed_(Neuse River Basin) Contractor: (List Construction Information below) Impoundment & Dam Outlet Structure & Pipe Modified Plunge Pool Material Supplies: (List below) Riser Structure DIP Pond Drain Gate Valve Outlet Pipe & Anti -Seep Collar 16024 O &M Manual Page 3 of 5 1/5/12 Project Name & Phase: Wildwood Subdivision Type of BMP: Wet Detention Pond Type of BMP: This manual established procedures for maintenance and operation of the (insert type of BMP this form shall be created specifically for each BMP). I. Maintenance See attached Operation & Maintenance Manual II. OPERATION See attached Operation & Maintenance Manual A. Record Keeping The Town of Holly Springs shall be provided with written inspection reports as specified in this manual. These reports shall be provided annually within 30 days of the anniversary of receipt of the "Stormwater BMP /O &M Responsibility Transfer" letter (form #16037). A professional engineer shall certify the reports. The Town of Holly Springs Engineering Department shall be notified as soon as any deficiencies in the detention structure are recorded. The Town shall be notified of the proposed methods to bring the structure into conformance and furthermore, the Town shall approve of any proposed work to be completed on any part of the structure prior to any work being started. After work has been completed the Town shall inspect and approve of the work before it shall be considered complete. After the Town approves the work an as -built drawing shall be completed and provided to the Town. Note: Operation of a BMP should include the following: • Annual & Quarterly Inspection Reports — a collection of a written inspection report should be kept on record, Inspection should be conducted at minimum quarterly and certified by a professional engineer annually. • Observations — all observations should be recorded. Where periodic inspections are performed following significant rainfall events, these inspections should be logged on the log forms found in Appendix D of the Town's Design Manual or created specifically for the project. • Maintenance — written records of maintenance and/or repairs should be recorded on the Operation & Maintenance Log Form found in Appendix D of the Town's Design Manual or created specifically for the project. • Other Operation Procedures — the owner should maintain a complete and up -to -date set of plans (as -built drawings) and all changes made to the dam over time should be recorded on the as- builts. Mylar and digital as- builts shall be provided to the Town each time they are updated. B. Sedimentation & Dredging Sedimentation from establishing areas tributary to the BMP may eventually result in the reduction of the storage volume and eventually will have to be removed. The frequency of this sediment removal can be reduced by ensuring that the site areas around the building be stabilized with a vegetative ground cover such that it restrains erosion. This would include a periodic application of fertilizer and other treatments necessary to promote a stable groundcover and minimize sedimentation to the BMP. The maintenance on this BMP requires that (provide design specific clean out information here). For aesthetic purposes it may be desirable to maintain it prior to this point. The removed material should be hauled offsite to a suitable landfill site or mounded somewhere on site and stabilized with a groundcover sufficient to restrain erosion. 16024 O &M Document Page 4 of 5 9.25.09 III. INSPECTION, OPERATION & MAINTENANCE LOGS (attach a blank copy of the applicable O&M log for each BMP) (attach 8 1/2 x 11 Location Map) (attach 81 /z x 11 copy of Recorded Plat(s)) (attach the Stormwater Management Plan, including form #16012 and As- builts) (attach Engineer Certifications for construction of each BMP) 16024 O &M Document Page 5 of 5 9.25.09 OPERATIONS & MAINTENANCE MANUAL (Beazer Vaughan Subdivision): Wet Detention Pond #3 This manual established procedures for maintenance and operation of the Beazer Vaughan Subdivision wet detention pond # 3. Maintenance of Embankments A. Vegetation The embankment has a ground cover of fescue, which if properly maintained will prevent erosion of the embankment and provide an easy surface for inspection. The grass will be most difficult to obtain in the area subject to water level fluctuation below the top of the riser. Grass should be fertilized every October and April. ♦ Re- Seeding — periodically re- seeding may be required to establish grass on areas where seek did not take or has been destroyed. Before seeding, fertilizer (12- 12 -12) should be applied at a minimum rate of 12 to 15 pounds per 1,000 SF. The seed should be evenly sewn at a rate of three pounds per 1,000 SF. The seed should be covered with soil to the depth of approximately ' / ". Immediately following the planting, the area should be mulched with straw. s Trees & Shrubs — trees, shrubs, and other landscape vegetation should be permitted only as shown on the approved planting plan. o Mowing — grass mowing, brush cutting and removal of weed vegetation will be necessary for the proper maintenance of the embankment. All embankment slopes and vegetation of spillways should be mowed when the grass exceeds 8" in height. Acceptable methods include the use of weed whips or power brush cutters and mowers. B. Erosion Erosion occurs when the water concentrates causing failure of the vegetation or when vegetation dies and sets up the environment for rill erosion and eventually gullies from the stormwater runoff. The dam should be inspected for these areas. Proper care of vegetative areas that develop erosion is required to prevent more serious damage to the embankment. Rills and gullies should be filled with suitable soil compacted and then seeded. Methods described in Section I-A, on vegetation, should be used to properly establish the grass surface. Where eroded areas are detected, the cause of the erosion should be addressed to prevent a continued maintenance problem. Frequently problems result from the concentration of runoff to one point of the embankment crest instead of a uniform distribution of runoff. This can be corrected by reshaping the crest to more evenly distribute the runoff to areas, which are not experiencing erosion problems. The top of the dam should not be allowed to be used for pedestrian or bicycle traffic. ♦ Abutment Areas -- the abutment is the line formed where the embankment fill comes into contact with the existing slope. Runoff from rainfall concentrates in these gutter areas and can reach erosive velocities because of the steep slopes. If a normal stand of grass cannot be maintained on the abutments, additional measures may be needed such as jute matting to provide for the establishment of a good ground cover. e Upstream Embankment Slope — Erosion problems can develop on the upstream face of the dam due to the fluctuation of water level in the pond. This is a result of a combination of wave actions and ground saturation, which occurs from the elevated water levels. The erosion generally occurs as the water level falls and the saturated ground becomes subjected to the wave action. If erosion becomes a problem, it may necessitate the installation of a stone armoring along the zone subject to fluctuating water level. This would consist of 18" of NCDOT Class B stone for erosion control underlain with Mirifi 140 geotextile fabric. It should be centered at the point of the erosion problem and covering an area 2' above and below the approximate center of the eroded area. C. Seepage ♦ Detection — due to the fact that the "permanent" impoundment level is only 5' deep, and the road embankment is immediately downstream and continuous with the dam embankment, seepage should not be expected on the downstream slope of the embankment. However, a cursory inspection of the road embankment should be made for completeness of the inspection. Seepage may vary in appearance from a soft wet area to a flowing spring. It may show up first as only an area where the vegetation is more lush and darker green. Cattails, reeds, mosses and other marsh vegetation often become established in a seepage area. The downstream abutment areas where the embankment fill and natural ground interface are very common locations for seepage. Also the contact between the embankment and the spillway conduit is a very common location which is generally attributed to poor compaction around the conduit. Due to the way in which conduits are put in, this is generally most evident on the underside of the conduit. Slides may result from excessively saturated embankment slopes. The natural foundation area immediately downstream of the dam abutment should also be inspected to ensure that "piping" is not occurring underneath the embankment. "Piping" may appear as a "boil" evident as spring carries soil. The soil usually deposits around the boil area and is evident by the sedimentary deposits accompanying it. Seepage can also occur into the spillway conduit through cracks in the pipe or improperly sealed joints. These can be seen by observing the conduit when the water level is high. The movement of the water itself is not dangerous, but if soil particles are being carried with it, then it can create a shortcut for the piping of soil. thrive on burrowing in the manmade earth embankments, which become pathways for seepage. In the event that burrows are detected within the dam, then the rodents should be dealt with by removal. II. MAINTENANCE OF SPILLWAYS & CONTROL STRUCTURES A. Inspection of Spillway Conduits Conduits should be inspected thoroughly once a year. Conduits should be visually inspected by actually entering the conduit a sufficient distance between the riser structure and the outlet to check all the joints. Because the outlet' works tie into the street storm sewer system, catch basins and pipes. Conduit should be inspected for proper alignment (sagging), elongation and displacement at joints, cracks, leaks, surface water, surface wear, loss of protective coating, corrosion and blocking. Problems with conduits most often occurs at joints and special attention should be given to them during inspection. Joints should be checked for gaps caused by elongation or settlement and loss of joint filler material. Open joints can permit erosion of the embankment material and possibly the piping of soil material through the joints. Catch basin should be checked for signs that water is seeping along the exterior surface of the pipe where it enters the catch basin. A depression in the soil surface over the pipe may be signs that soil is being removed from around the pipe. ♦ What to do if problems are detected with the spillway: Retain the assistance of a civil engineer or geotechnical engineer qualified in the design of embankments to perform an inspection of the dam. If in doubt, lower the water surface elevation of the pond until such time as an inspection can be performed by a qualified professional. B. Trashracks on Pipe Spillways The spillway riser and rip -rap weir for this dam is the only spillway structures. The intake structure has been fitted with a trashrack to prevent debris from entering the spillway structure. Most of the runoff entering the pond comes in through grated inlets, which have essentially provided filtration of the runoff and should limit the size of the debris that enters the basin to floating debris which will most likely pass through the trashrack. The opening between the trashrack and riser is smaller than the opening of the outlet pipe. The intent is that any debris, which passes through the trashrack, will be easily passed by the pipe outlet. Maintenance should include periodically checking the rack for rusted or broken sections and repairing as needed. The trashrack should be checked frequently during and after storm events to ensure that it is properly functioning and to remove accumulated debris. III. OPERATION A. Lake Drains Lake drains should always be operable so that the pool level can be drawn down in case of an emergency or for repairs or maintenance. Lake drain valves or gates that have not been operated for a long time present a special problem. Generally, when draining the pond, it should be drained slowly. Open the drain until a good flow of water is present but not a torrent, so that the water level can be drained over a period of 48 hours or more. Rapidly lowering the water level in the pond can cause permanent damage to the embankment and must be avoided. The gate valve controlling the lake drain should be operated from fully closed to fully opened position at least twice a year. THE TOWN OF Molly Springs NORTH CAROLINA Stormwater BMP Operation & Maintenance Log Wet Detention Basin TOWN OF HOLLY SPRINGS ENGINEERING DEPARTMENT Project Information & BMP Identification Project Name: Beazer Vaughan Subdivision TOHS Project Number: 13 -DO -02 Project Location: Ralph Stephens Road PIN Number: 0658133419/0658034571 Property Owner: Beazer Homes - Raleigh BMP Location: West Side of Street A BMP Element Operation Inspection Maintenance Inspection Date: Maintenance Required? Maintenance Completed? By: ❑ Yes ❑ Yes Type of Inspection: Quarterly or Annual ❑ No ❑ No Last Rainfall Date: Description: Description: Last Rainfall Amount: Maintenance Required? Maintenance Completed? Today's Weather: ❑ Yes ❑ Yes Photo Attached & Name: I ❑ ❑ No ❑ Description: BMP Element Status Maintenance Completed Entire BMP Maintenance Required? Maintenance Completed? ❑ Yes ❑ Yes ❑ No ❑ No Description: Description: Drainage Area & Maintenance Required? Maintenance Completed? Perimeter of the BMP ❑ Yes ❑ Yes ❑ No ❑ No Description: Description: Inlet Device: pipe or swale Maintenance Required? Maintenance Completed? ❑ Yes ❑ Yes ❑ No ❑ No Description: Description: Forebay Maintenance Required? Maintenance Completed? ❑ Yes ❑ Yes F] No F-1 No Description: Description: Vegetated Shelf Maintenance Required? Maintenance Completed? ❑ Yes ❑ Yes ❑ No ❑ No Description: Description: 16015 Wet Deterntion Basin O &M 4.1.08 Page 1 of 3 THE TOWN OF Molly Springs NORTH CAROLINA Stormwater BMP Operation & Maintenance Log Wet Detention Basin TOWN OF HOLLY SPRINGS ENGINEERING DEPARTMENT Aquatic Environment Maintenance Required? Maintenance Completed? ❑ Yes ❑ Yes F-1 No F-1 No Description: Description: Main Treatment Area Maintenance Required? Maintenance Completed? ❑ Yes ❑ Yes ❑ No ❑ No Description: Description: Embankment Maintenance Required? Maintenance Completed? ❑ Yes ❑ Yes ❑ No ❑ No Description: Description: Outlet Device Maintenance Required? Maintenance Completed? ❑ Yes ❑ Yes ❑ No ❑ No Description: Description: Receiving Water Maintenance Required? Maintenance Completed? ❑ Yes ❑ Yes ❑ No ❑ No Description: Description: General Comments, Sketches & Field Measurements (attach if necessary): Include Date & Initials 16015 Wet Deterntion Basin O &M 4.1.08 Page 2 of 3 AKTHE TOWS OF Stormwater BMP Operation & Maintenance Log - HoUy Springs Wet Detention Basin NORTH CAROLINA TOWN OF HOLLY SPRINGS ENGINEERING DEPARTMENT Annual Engineer's Certification of Stormwater BMP Operation & Maintenance Note: this section is not required to be filled out for quarterly inspections 11 , a Licensed Professional Engineer in the State of North Carolina, Print Name do hereby certify that the Stormwater BMP Wet Pond Type Constructed as a part of Beazer Vaughan Tract , project located at Name of Project the west side of Street A. Size /lot/general description has been maintained in substantial accordance with the approved plans and specifications, dated: Date This is certification is based on my field observation during the periodic & annual operation and maintenance inspections and other methods as follows (if applicable): Seal Date: 16015 Wet Deterntion Basin O &M 4.1.08 Page 3 of 3 NM Level Spreader FES 200 L-CVC- BEAZER VAUGHAN SUBDIVISION BMP LOCATION MAP I BMP 4 "r-m 1 Y N[" .RPFiIAIla3 =Z Permit Number: (to be provided by DWQ) Drainage Area Number: Filter Strip, Restored Riparian Buffer and Level Spreader Operation and Maintenance Agreement I will keep a maintenance record on this BMP. This maintenance record will be kept in a log in a known set location. Any deficient BMP elements noted in the inspection will be corrected, repaired or replaced immediately. These deficiencies can affect the integrity of structures, safety of the public, and the removal efficiency of the BMP. Important maintenance procedures: — Immediately after the filter strip is established, any newly planted vegetation will be watered twice weekly if needed until the plants become established (commonly six weeks). — Once a year, the filter strip will be reseeded to maintain a dense growth of vegetation — Stable groundcover will be maintained in the drainage area to reduce the sediment load to the vegetation. — Two to three times a year, grass filter strips will be mowed and the clippings harvested to promote the growth of thick vegetation with optimum pollutant removal efficiency. Turf grass should not be cut shorter than 3 to 5 inches and may be allowed to grow as tall as 12 inches depending on aesthetic requirements (NIPC,1993). Forested filter strips do not require this type of maintenance. — Once a year, the soil will be aerated if necessary. — Once a year, soil pH will be tested and lime will be added if necessary. After the filter strip is established, it will be inspected quarterly and within 24 hours after every storm event greater than 1.0 inch (or 1.5 inches if in a Coastal County). Records of operation and maintenance will be kept in a known set location and will be available upon request. Inspection activities shall be performed as follows. Any problems that are found shall be repaired immediately. BMP element: Potential problem: How I will remediate the problem: The entire filter strip Trash/ debris is present. Remove the trash /debris. ...system The flow splitter device (if applicable) The flow splitter device is clogged. Unclog the conveyance and dispose of any sediment off -site. The flow splitter device is Make any necessary repairs or damaged. replace if damage is too large for repair. Form SWU401 -Level Spreader, Filter Strip, Restored Riparian Buffer O &M -Rev.3 Page 1 of 3 BMP element: Potential problem: How I will remediate the problem: The swale and the level lip The Swale is clogged with sediment. Remove the sediment and dispose of it off -site. The level lip is cracked, Repair or replace lip. settled, undercut, eroded or otherwise damaged. There is erosion around the Regrade the soil to create a berm end of the level spreader that that is higher than the level lip, and shows stormwater has then plant a ground cover and bypassed it. water until it is established. Provide lime and a one -time fertilizer application. Trees or shrubs have begun Remove them. to grow on the Swale or just downslo e of the level lip. The bypass channel Areas of bare soil and /or Regrade the soil if necessary to erosive gullies have formed. remove the gully, and then reestablish proper erosion control. Turf reinforcement is Study the site to see if a larger_ damaged or ripap is rolling bypass channel is needed (enlarge if downhill. necessary). After this, reestablish the erosion control material. The filter strip Grass is too short or too long Maintain grass at a height of (if applicable). approximately three to six inches. Areas of bare soil and /or Regrade the soil if necessary to erosive gullies have formed. remove the gully, and then plant a ground cover and water until it is established. Provide lime and a one -time fertilizer application. Sediment is building up on Remove the sediment and the filter strip. restabilize the soil with vegetation if necessary. Provide lime and a one- time fertilizer application. Plants are desiccated. Provide additional irrigation and fertilizer as needed. Plants are dead, diseased or Determine the source of the dying. problem: soils, hydrology, disease, etc. Remedy the problem and replace plants. Provide a one -time fertilizer application. Nuisance vegetation is Remove vegetation by hand if choking out desirable species. possible. If pesticide is used, do not allow it to get into the receiving water. The receiving water Erosion or other signs of Contact the NC Division of Water damage have occurred at the Quality local Regional Office, or the outlet. 401 Oversight Unit at 919 - 733 -1786. Form SWU401 -Level Spreader, Filter Strip, Restored Riparian Buffer O &M -Rev.3 Page 2 of 3 Permit Number: (to be provided by DWQ) I acknowledge and agree by my signature below that I am responsible for the performance of the 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. Project name: Wildwood Subdivision BMP drainage area number: 200 Print name: Chris Simmering Title: Director Land Development Address:4509 Creedmoor Rd Suite 200 Raleigh NC 27612 Phone:(919) 277 -2406 Signature: Date: 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, a Notary Public for the State of , County of , do hereby certify that personally appeared before me this day of , and acknowledge the due execution of the forgoing filter strip, riparian buffer, and /or level spreader maintenance requirements. Witness my hand and official seal, SEAL My commission expires Form SWU401 -Level Spreader, Filter Strip, Restored Riparian Buffer O &M -Rev.3 Page 3 of 3 THE TOWN OF oKMolly Springs NORTH CAROLINA Stormwater BMP Operation & Maintenance Log Level Spreader TOWN OF HOLLY SPRINGS ENGINEERING DEPARTMENT Project Information & BMP Identification Project Name: Wildwood Subdivision TOHS Project Number: 13 -DO -02 Project Location: Ralph Stephens Road PIN Number: 0658133419/0658034571 Property Owner: Beazer Homes - Raleigh BMP Location: Outlet 200 Located at south side of Wildwood Farm station 23 BMP Element Operation Inspection Maintenance Inspection Date: Maintenance Required? Maintenance Completed? By: ❑ Yes ❑ Yes Type of Inspection: Quarterly or Annual ❑No ❑No Last Rainfall Date: Description: Description: Last Rainfall Amount: Maintenance Required? Maintenance Completed? Today's Weather: ❑ Yes ❑ Yes Photo Attached & Name: ❑ ❑ No ❑ Description: BMP Element Status Maintenance Completed Rip -Rap Maintenance Required? Maintenance Completed? ❑ Yes ❑ Yes ❑No ❑No Description: Description: Plunge Pool Lip Maintenance Required? Maintenance Completed? ❑ Yes ❑ Yes ❑ No ❑ No Description: Description: Filter Strip Maintenance Required? Maintenance Completed? ❑ Yes ❑ Yes ❑No ❑No Description: Description: 16014 Level Spreader O &M 4.1.08 Page 1 of 2 — TOwNOF Stormwater BMP Operation & Maintenance Log Sprrings ings Level Spreader NORTH CAROLINA TOWN OF HOLLY SPRINGS ENGINEERING DEPARTMENT General Comments, Sketches & Field Measurements (attach if necessary): Include Date & Initials Annual Engineer's Certification of Stormwater BMP Operation & Maintenance Note: this section is not required to be filled out for quarterly inspections I, , a Licensed Professional Engineer in the State of North Carolina, Print Name do hereby certify that the Stormwater BMP Constructed as a part of Type project located at Name of Project Size /lot/general description has been maintained in substantial accordance with the approved plans and specifications, dated: Date This is certification is based on my field observation during the periodic & annual operation and maintenance inspections and other methods as follows (if applicable): e Date: 16014 Level Spreader O &M 4.1.08 Page 2 of 2