Glossary of terms

Brown and Caldwell Publications: Brown and Caldwell; 1996 (October); Stormwater Retrofit Options for Valley County, Technical Memorandum; 9p + attachments. A preliminary list of best management practices (BMPs) and projects for Valley County as a remedy for stormwater quantity and quality problems. Details challenges and recommendations for specific areas as follows: Urbanized areas: Higher relative runoff is present due to more impervious surfaces, runoff often contains higher concentrations of pollutants (sediments, heavy metals, nutrients, bacteria, etc.) than in natural areas. BMPs recommended include stormwater filters, catch basin inserts, and constructed wetlands in appropriate areas for control of stormwater discharge, improved drainage ditch maintenance, specific practices for erosion control at construction sites, specific guidance for a number of subdivisions, storm drain and culvert inlet modifications, and animal waste control to decrease bacterial discharges into public-use water areas. Agricultural areas: Major runoff concern is erosion (crop and grazing lands), resulting in both and increased sediment load and a corresponding deposition of adsorbed nutrients. BMPs recommended include conservation tillage and buffer/filter strips along stream banks for cropland, use of irrigation ponds as detention mechanisms for peak-flow reductions, seeding and fencing in impacted grazing areas to restore riparian vegetation, check dams and culvert modification to control stream-bank erosion. Residences in the surrounding hills: Major runoff concern is erosion as in agricultural areas. BMPs recommended include improvements to private roads including stabilization and drainage culverts, seeding, terracing, retaining walls or other slope stabilization measures to reestablish vegetation or otherwise improve stability in eroding slopes, and improvement of' existing ponds for use as detention basins to reduce peak-flow. Waterside property: Runoff concerns include both erosion and pollutant loads. These areas often have steep slopes and impervious surfaces, combined with limited space for BMPs. Recommendations include those listed for residences in the surrounding hills (above) as well as vegetation strips along existing surface water bodies and roads, and waste management and erosion control measures in public access locations such as boat ramps and docks. Transportation corridors: Roadways represent a major source of stormwater pollution problems. Recommendations include restriction of vehicle access to the Old State Highway, street sweeping to remove winter "grit" in sensitive areas, proper disposal of cleared snow in areas with appropriate containment, and barriers and weather sensitive limitations for bridge and pier maintenance.