http://www.usgs.gov/water/ http://www.usgs.gov/water/ The storm system drains all the "hardware" in an urban or suburban area — roofs, roads, parking lots, and

http://www.usgs.gov/water/ http://www.usgs.gov/water/ The storm system drains all the "hardware" in an urban or suburban area — roofs, roads, parking lots, and sometimes even constantly mowed grass (which can form subterranean hardpan). Higher runoff rates lead to flow bottlenecks, flooding, and untreated sewage discharge. Still, agricultural land has more catchment.