Many of the stormwater problems in natural areas originate off site in developed landscapes and may require complicated negotiations with adjacent landholders and public regulatory agencies to resolve. Sadly, many stormwater management regulations are applied only to new development and are nonexistent and unenforced in urban areas, where all runoff is simply shunted to the nearest stream via a storm sewer. Where regulations apply, stormwater design often focuses on flooding only and may not provide any detention of the smaller, but very frequent one or two-year storms, which shape the stream channel and, if dramatically increased in volume, lead to severe disturbance, including
bank undercutting, channel
migration, and
sedimentation.
Even seemingly remote forest tracts are not exempt from extreme changes in hydrologic regimen. Major highways routinely cause severe disruptions in natural hydrologic patterns, affecting large areas of rural land. Where logging is undertaken, even in supposedly "protected" national and state forestlands, stream corridors are ravaged and runoff is dramatically increased, at least temporarily, especially by clear cutting. The longer term impacts of the required access roads are more severe, altering drainage surface patterns and, where road cuts are used, create permanent seeps which literally bleed the groundwater away, affecting the water table over a wide area.
Stormwater management is best addressed over the entire watershed. The simplest approach usually is to seek multiple solutions at different points, rather than a single cure-all at the point of discharge. We must look first for solutions which most closely mimic nature's solutions, which will likely maximize opportunities for recharge. Sometimes simply altering the management of landscapes can effect substantial reductions in runoff. Turf areas, when even only gently sloped, shed water nearly as
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