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Dawson County Public Works TYPICAL MAINTENANCE ACTIVITIES FOR PONDS Cited from the Georgia Stormwater Management Manual Vol.2 section 3.2-14 / Routine Clean and remove debris from inlet and outlet structures. Make sure exterior and interior slopes of easements are cleared to have accessibility to ponds. Trees are not allowed in dams or in drainage easements. Slope stabilization however is necessary to prevent erosion. Semiannual Inspection Remove debris and trash from basin surface to minimize outlet clogging and improve functionality. If wetland components are included, inspect for invasive vegetation. Annual Inspection Inspect for damage, paying particular attention to the control structure. Check for signs of eutrophic conditions in wet ponds. Note signs of hydrocarbon build-up, and remove appropriately. Monitor for sediment accumulation in the facility and forebay (area that flows into pond). Examine to ensure that inlet and outlet devices are free of debris and are operational. Check control gates, valves or other mechanical devices. As needed Repair undercut or eroded areas. Seed or sod to restore dead or damaged ground cover. Remove litter/debris. Perform structural repairs to inlets and outlet. 5 to 7 Years or after 50% of the total forebay capacity have been lost. Perform wetland plant management and harvesting. Remove accumulated sediment from the forebay. Ten-20 years or after 25% of the permanent pool volume have been lost. Monitor sediment accumulation, and remove sediment when the pond volume has become reduced significantly, or the pond becomes eutrophic. 10-20 years or after 25% of the permanent pool volume has been lost. Additional Maintenance Considerations and Requirements A sediment marker should be located in the forebay to determine when sediment removal is required. Sediment excavated from stormwater ponds that do not receive runoff from designated hotspots are not considered toxic or hazardous material and can be safely disposed of either land application of landfilling. Testing may be required prior to sediment disposal. Periodic mowing of the pond buffer is only required along maintenance right-of-way and the embankment. The remaining buffer can be managed as a meadow (mowing every other year) or forest. Care should be exercised during pond drawdowns to prevent discharges of sediments, anoxic water, or high flows with erosive velocities. The approving jurisdiction should be notified before draining stormwater pond.