Storm sewers reduce local flooding by worsening downstream flooding.

Evidence

Even when the storm sewers in a subdivision worked properly, the survey investigations demonstrated, the artificial drainage system could cause problems downstream. The outlet for storm drains was generally the nearest large stream, so the sewer system forced the stream to carry a tremendous burden after a hard rain. Instead of soaking into the ground or evaporating or flowing into a network of drainage channels, the storm water in the sewered area rushed to the stream in a few minutes or hours. Thus, the sewer system solved a problem in one area by creating a problem in another place: The increased stream flow made houses in downstream communities more vulnerable to flooding. — Adam Rome, The Bulldozer in the Countryside, 807

Categorization

• XREF: connects to: Builders’ site design decisions, not roof and pavement area alone, drive suburban flooding. — Adam Rome, The Bulldozer in the Countryside:…, 805; Contradictory engineered water management signals the loss of flood equilibrium — Aldo Leopold, A Sand County Almanac: With Other…, 424; Hillside grading upstream imposes downstream water, flood, and navigation costs — Adam Rome, The Bulldozer in the Countryside:…, 668 (+3 more)

Broader Connections

• Flood barriers that protect one area flood its neighbors instead #corroborates (0.95) — Albert Bandura, Moral Disengagement, 2777
• Engineers framed preserved wetlands as natural flood-control infrastructure #expands (0.75) — Adam Rome, The Bulldozer in the Countryside, 510