Scalped suburban watersheds erode at roughly fifty times undisturbed rates

Evidence

In our country, with its history of rampaging rivers and gullied hillsides, no one should have to be reminded of the function of natural plant cover in holding soil and water. The story of erosion and of the siltation of streams and rivers, which destroys aquatic life, clogs channels, and causes floods, has been told frequently and well, but generally in terms of bad farming practices. Less well understood is the extent to which the damage is compounded by bulldozing off the vegetation and topsoil, during the development of subdivisions. The District of Columbia’s famous Rock Creek, which winds through its chief park after draining an adjacent part of Maryland, tends to flood twice as badly as it did twenty years ago. You know why when you read a statement by Harold P. Guy of the United States Geological Survey pointing out how the water-holding capacity of the watershed has been reduced, as for example in a subdivision in Kensington, Maryland, from which “nearly all of the trees were removed and the natural waterways were altered.” After this scalping, each inch of runoff from rain falling on the area carried about 250 tons of sediment into Rock Creek, or about fifty times as much as from an equivalent undeveloped watershed. … Further reading tells you that in the Washington area as a whole streams now move about 1,000,000 tons of sediment a year, helping to explain why game fishing has suffered so severely in the lower Potomac and why experts debated the ways and means of keeping the Washington harbor open in the future. — Adam Rome, The Bulldozer in the Countryside, 898

Categorization

• recurring: this claim recurs 2 times within its source
• XREF: connects to: Federal studies proved suburbanization doubled to quadrupled storm runoff by 1970 — Adam Rome, The Bulldozer in the Countryside:…, 803; Bulldozed suburban lawns shed rainwater almost like concrete. — Adam Rome, The Bulldozer in the Countryside:…, 810; Housing construction sites erode at hundreds of times farmland rates — Adam Rome, The Bulldozer in the Countryside:…, 820 (+4 more)

Broader Connections

• Suburban sprawl created flood damage faster than engineered protections could counter #expands (0.80) — Adam Rome, The Bulldozer in the Countryside, 698
• Apparent farm solvency conceals ongoing topsoil loss to erosion #expands (0.78) — Aldo Leopold, A Sand County Almanac, 425
• A fine-grained patch mosaic can retain watershed nutrients better than large managed patches #complicates (0.70) — S. T. A. Pickett and P. S. White, eds., The Ecology of Natural Disturbance and…, 1991