Construction & Post-Construction Stormwater Ordinance

City of Wenatchee, Public Works Department

Jessica Shaw, Environmental Manager

Eastern WA Phase II Municipal Stormwater Permit

Issued by Department of Ecology to cities and counties with specific urban densities in 2007.

Passes along federal stormwater regulations and additional state requirements.

Sets forth a timeline for cities/counties to adopt stormwater regulations and implement a stormwater program

Stormwater Program Elements

1. Public Education & Outreach2. Public Involvement & Participation3. Illicit Discharge Detection & Elimination4. Construction Site Stormwater Runoff

Control5. Post-Construction Stormwater

Management for New Development & Redevelopment

6. Pollution Prevention & Good Housekeeping for Municipal Operations

Construction & Post-Construction Regulatory Requirements

Adopt an ordinance addressing construction site runoff and post-construction management of stormwater facilities no later than February 16, 2010.

The ordinance must become effective no later than February 16, 2011.

The Eastern WA Phase II Municipal Stormwater Permit also specifies minimum requirements for the ordinance.

Minimum Ordinance RequirementsConstruction & Post-Construction

The ordinance shall at a minimum apply to construction sites disturbing greater than or equal to one acre, and to construction projects less than one acre that are part of a common plan of development or sale.◦ Example: ¼ acre lot, that is part of a 2 acre

subdivision. All lots within the initial development are regulated.

Minimum Ordinance RequirementsConstruction & Post-Construction

Provide enforcement procedures & actions

Insure access to inspect construction and post-construction stormwater BMPs located on private properties that discharge to the stormwater system

Adopt the Stormwater Management Manual for Eastern Washington (or other DOE approved manual)

Minimum Ordinance RequirementsConstruction

Construction site operators must: Prepare a Construction Stormwater

Pollution Prevention PlanImplement appropriate erosion &

sediment control Best Management Practices (BMPs)

Control waste (concrete washout, litter, chemicals, discarded building supplies)

Minimum Ordinance RequirementsPost Construction

Project proponents and property owners must:

Insure the BMP selection, design, installation, operation, and maintenance meet minimum technical requirements.

Implement appropriate runoff treatment, flow control & source control BMPs

Provide adequate ongoing long-term operation & maintenance of BMPs