Stormwater manuals

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Our stormwater manuals provide stormwater permit implementation and management guidance. To determine which manual you need, contact your municipality or permit administrator.

Order a hard copy or CD

Between versions: What changed and why?

Other manuals for management and design

Manual equivalency

In some cases, municipal stormwater permittees have the option of either adopting portions of the appropriate Stormwater Manual or portions of a regional manual determined to be equivalent to the Ecology manual.

Other resources