The city of Rapid City is a Phase II National Pollutant Discharge Elimination System (NPDES) community and is required to have an MS4 permit. As part of their NPDES permit activities, the City sponsored training sessions for local engineers, home builders, developers, and City staff that focused on erosion control primarily for construction and development activities.
RESPEC staff worked with the City to develop training materials including training presentations and practice problems for creating erosion control plans based on hypothetical construction and development projects. Special attention was given to construction and postconstruction stormwater best management practices (BMPs) including new design techniques for low impact development (LID). Example problems included the use of a rainfall design depth to determine the water-quality control volume for stormwater BMPs and incorporating LID techniques to reduce the amount of impervious area contributing directly to stormwater runoff, therefore, lowering the required water-quality capture volume for individual BMPs. Four individual training sessions were held, and a stormwater drainage tour in downtown Rapid City was held. In addition to the training, RESPEC was contracted to review and edit the City’s Stormwater Quality Manual and three new ordinances that are now adopted by the city for controlling erosion during and postconstruction.