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Home My WebLink About20200941 Ver 2_12_ACC Pond Drainage Plans_REV_20210120Pond Drainage Plan - Albemarle Corporate Center Pond PE POND PE PROPERTIES: Acreage - 0.60 Depth — 1-5 ft Nearest Upstream Stream - Poplin Branch (NCDWR Best Usage Classification-C) Nearest Downstream Stream - Poplin Branch (NCDWR Best Usage Classification-C) NC Dam Safety Inventory List - No The pond will be drained, and Poplin Branch restored to its natural state. The following criteria will be adhered to ensure the dewatering of the pond will not result in avoidable impacts to the environment and downstream streams and wetlands: Pond PE is downstream of Pond PF, which are connected via a culvert below the earthen dam/roadway that separates the two ponds. Poplin Branch will be blocked from entering the pond complex upstream of Pond PF using sandbags or other impediment and pumped around to discharge into Poplin Branch downstream of Pond PE through a BMP device that will divert the re -directed water, reduce velocity, and avoid erosion, if necessary. The pond will be dewatered via a top -down water withdrawal from a float pump. Clean top water from the pond will be discharged over a BMP device to slow the velocity before it enters Poplin Branch down- stream of Pond PE. When the top clean water is gone, the water will then be pumped into a silt bag, or similar device, that reduces the water turbidity and velocity before being discharged into Poplin Branch. A conceptual plan for the placement of the components and the specific component types will be devel- oped with the contractor and provided to interested stakeholders. If some other method is used to dewater, a fine mesh net or screen will be placed over the dewatering structure inlet (if possible) and outlet to catch any fish or wildlife, so as to prevent them from entering the receiving water. 4. Pictures will also be taken during and after drawdown of: • The pond, stream banks, effluent entry point into the receiving water, the receiving stream up- stream and downstream of the pond discharge point. 5. A Preliminary Stream and Riparian Area Restoration Plan has been developed in conjunction with the Pond Drainage Plan. The permitting agencies will be provided the Draft plan in advance of the pond drainage and afforded the opportunity to visit the site to provide input on the Final Stream and Riparian Area Res- toration Plan once the ponds are drained. Breaching of the earthen dam on the downstream end of Pond PE will not occur until both ponds have been successfully drained. Water flow from Poplin Branch that was diverted around the pond complex prior to drainage will not be restored through the drained pond reach until the appropriate items from the restoration plan have been implemented and the action is approved by regulatory agencies. The Restoration Plan includes the following: Three Oaks Engineering threecahsenip neering.cam • Restoration goals; • Success criteria; • Pre/post longitudinal cross -sectional drawings (latter after ponds are drained); • Channel stabilization structure schemat- ics (may also include some general plan to address unstable areas); • Grading plan, • Planting plan, • Monitoring plan, • Long-term protection methodology for restored reach (e.g., easement, deed re- striction). Three Oaks Engineering Pond Drainage Plan - Albemarle Corporate Center Pond PF POND PF PROPERTIES: Acreage - 0.53 Depth — 1-8 ft Nearest Upstream Stream - Poplin Branch (NCDWR Best Usage Classification-C) Nearest Downstream Stream - Poplin Branch (NCDWR Best Usage Classification-C) NC Dam Safety Inventory List - No The pond will be drained, and Poplin Branch restored to its natural state. The following criteria will be adhered to ensure the dewatering of the pond will not result in avoidable impacts to the environment and downstream streams and wetlands: Pond PF is upstream of Pond PE. Poplin Branch will be blocked from entering the pond using sandbags or other impediment and pumped around to discharge into Poplin Branch downstream of Pond PE through a BMP device that will divert the re -directed water, reduce velocity, and avoid erosion, if necessary. This effort will be the same as for Pond PE and will not be duplicated. The pond will be dewatered via a top -down water withdrawal from a float pump. Clean top water from the pond will be discharged over a BMP device to slow the velocity before it enters Poplin Branch down- stream of Pond PE. When the top clean water is gone, the water will then be pumped into a silt bag, or similar device, that reduces the water turbidity and velocity before being discharged into Poplin Branch. A conceptual plan for the placement of the components and the specific component types will be devel- oped with the contractor and provided to interested stakeholders. If some other method is used to dewater, a fine mesh net or screen will be placed over the dewatering structure inlet (if possible) and outlet to catch any fish or wildlife, so as to prevent them from entering the receiving water. 4. Pictures will also be taken during and after drawdown of: • The pond, stream banks, effluent entry point into the receiving water, the receiving stream up- stream and downstream of the pond discharge point. 5. A Preliminary Stream and Riparian Area Restoration Plan has been developed in conjunction with the Pond Drainage Plan. The permitting agencies will be provided the Draft plan in advance of the pond drainage and afforded the opportunity to visit the site to provide input on the Final Stream and Riparian Area Res- toration Plan once the ponds are drained. Breaching of the earthen dam on the downstream end of Pond PE will not occur until both ponds have been successfully drained. Water flow from Poplin Branch that was diverted around the pond complex prior to drainage will not be restored through the drained pond reach until the appropriate items from the restoration plan have been implemented and the action is approved by regulatory agencies. The Restoration Plan includes the following: Three Oaks Engineering threecahsenip neering.cam • Restoration goals; • Success criteria; • Pre/post longitudinal cross -sectional drawings (latter after ponds are drained); • Channel stabilization structure schemat- ics (may also include some general plan to address unstable areas); • Grading plan, • Planting plan, • Monitoring plan, • Long-term protection methodology for restored reach (e.g., easement, deed re- striction). Three Oaks Engineering Pond PE ®am Pond PE from East side Three Oaks Engineering threecahsenip neering.cam I tr k Ir &,- at Im.. A try #7A m� It 0 Road/dam between ponds PE and PF Three Oaks Engineering threecahsenip neering.cam