7/29/2019 Stormwater Construction Permit

1/1

What environmental issues are involved?During the course of site preparation, the removal of

trees, meadow grasses and agricultural crops causes ero-sion. Natural depressions that temporarily pond water arethen graded to a uniform slope, causing rapid runoff.Clearing and grading results in compaction, which greatlyreduces water absorption capabilities.

The resulting storm water runoff from these constructionactivities can have a significant impact on water quality. Asstorm water flows over the disturbed land of a constructionsite, it picks up pollutants like sediment, debris and chemi-cals and transports them to a nearby storm sewer systemor directly to a river, stream or lake.

Polluted storm water runoff can harm or kill fish and

other wildlife. Sedimentation can destroy aquatic habitat,and high volumes of runoff can cause stream bank ero-sion. Debris can clog waterways and potentially reach theocean where it can kill marine wildlife and impact habitat.

Who needs the permit?Because construction sites can be a significant source of

these pollutants, all construction site operators engaged inclearing, grading and excavating activities that disturbone acre or more of land are required to obtain permitcoverage for their construction storm water discharges.The permit is also required for smaller sites that are part ofa larger, common plan of development.

The storm water construction permit requires operatorsof such construction sites to implement storm water con-trols and develop storm water pollution prevention plans toprevent pollutants from being discharged in storm waterrunoff.

The storm water permits are implemented based on bestmanagement practices (BMPs) such as diversion, deten-tion, erosion control, sediment traps, gravel constructionentrances, covered storage, spill response, stream bufferzones and good housekeeping. These techniques helpcontrol nonpoint source pollution by intercepting surfacerunoff from disturbed areas, filtering and treating it, andthen discharging it at a controlled rate.

Documentation and accountability are also importantaspects of the permits. Permittees are required to conductinspections weekly and the day after any rainfall eventresulting in runoff. They must also maintain on-site copiesof written inspection reports and any associated enforce-ment actions.

In a move to further protect the waters of the Common-wealth, certain construction projects are ineligible for cov-erage under the 2009 general storm water permit. Specifi-cally, permits will not be issued for projects that:

Discharge to an Impaired Water listed in the 2009 305

Integrated Report as impaired for sediment and for whichan approved Total Maximum Daily Load has not been pre-pared. Discharge into a Cold Water Aquatic Habitat, an Exce

tional Water or an Outstanding State Resource Water.Problems related to erosion runoff

Sedimentation Sediment is one of the biggest sources owater pollution in Kentucky and the nation. Sedimentationcan destroy aquatic habitat, and high volumes of runoff cacause stream bank erosion. Polluted storm water runoff ca

harm or kill fish and other wildlife and damage recreationaareas. Debris can clog waterways and potentially reach thocean where it can kill marine wildlife and impact habitat.Inflow of sediment can cloud water, blocking sunlight fromsubmerged plants. Sediment also settles to the bottom ofstreams, clogging the gravel beds used by fish for layingtheir eggs.Chemicals -- Nutrients, such as phosphorus and nitrogenfrom fertilizers enter the water and promote unusually rapialgae growth. As this algae dies, its decomposition reduceor eliminates oxygen needed by fish, shellfish and otheraquatic life for survival.Post-construction runoff-- Roof tops, roads, parking lots

driveways and other impervious surfaces prevent rainfall tsoak into the ground. Consequently, most rainfall is con-verted directly to runoff. The increase in storm water can btoo much for the existing natural drainage system to han-dle. As a result, the natural drainage system is often altereto rapidly collect runoff and quickly convey it away (usingcurb and gutter, enclosed storm sewers and lined chan-nels). The storm water runoff is subsequently discharged tdownstream waters such as streams, reservoirs, lakes orestuaries.

Basic principles of erosion prevention

Preserve existing vegetation as much as possible Mulch or seed bare soil immediately for the best and

cheapest erosion protection

Use silt fences, brush barriers or other approaches topond and filter sediment from runoff

Install silt check dams made of rock, brush or otherproducts to prevent ditch erosion and remove sedimen

Protect inlets and outlets

Settle out soil particles in sediment traps and basins

January 2011

Fact Sheet

Storm Water General Permitfor Construction Activities

Kentucky Division of Water200 Fair Oaks Lane, 4th floorFrankfort, KY 40601502-564-3410Water.ky.gov