is rainfall that accumulates in natural and/or man-made storage and STORMWATER SYSTEMS during and immediately following a storm event.

Consists of runoff from rain, irrigation and other urban and rural sources.

Water originating from rain or other outside sources that does not enter the sewer.

Runoff water resulting from precipitation. See Categories of Needs: Category VI.

Rainfall that does not percolate into the ground or evaporate.

rain water runoff, snow or ice melt runoff, surface runoff and drainage.

Rainfall or other forms of precipitation. Storm water runoff is the result of storm water washing across impervious surfaces, carrying with it the pollutants found on streets, parking lots, rooftops, etc. These pollutants end up in streams and rivers. Storm water runoff contributes from 60 to 80% of total water pollution.

Rain and snow runoff from the urban landscape, primarily impervious surfaces. Storm water often transports water pollutants such as heat, bacteria, litter, suspended solids, nutrients, metals, and organic chemicals. Sources of these pollutants include warm pavement, pet waste, construction site erosion, road salt and sand, lawn fertilizer, shingles and gutters, gasoline, oil, and antifreeze. The quantity of storm water runoff from impervious surfaces is also a problem, causing stream bank erosion and destruction of habitat for fish and other stream biota.

Rainwater runoff, snow melt runoff, surface water runoff, and discharges that are collected by storm sewers. Also see "National Pollutant Discharge Elimination System (NPDES)."

Rainwater that has reached the surface and has begun soaking into the ground or running off into the storm sewer.

Precipitation that accumulates in natural and/or constructed storage and storm water systems during and immediately following a storm event.