Erosion & Sediment Control Plan (ESC Plan)

What is an erosion and sediment control plan?

Controlling erosion and preventing sediment and other pollutants from leaving the project site during construction can be achieved by implementing the best management practices(BMPs) identified in the SRSM. The ESC plan shall outline specific construction BMPs for a project site to avoid adverse stormwater impacts from construction activities on water resources, roads, drainage facilities, surrounding properties and other improvements.

When is an ESC plan required?

Land-disturbing activities are activities that result in a change in existing soil cover (vegetative or non-vegetative) or site topography. Land-disturbing activities include, but are not limited to, demolition, construction, clearing and grubbing, grading and logging. The following land-disturbing activities require and ESC plan:

  • five thousand square feet or greater in area; or
  • in a special site per SMC 17D.090.080

An ESC plan, when required, must be submitted with either the road and drainage plans or the permit application, prior to any land-disturbing activity.

What projects are exempt from an ESC plan?

An ESC plan is typically not required for the following activities:

  • Commercial agriculture as regulated under RCW Chapter 84.34.020;
  • Forest practices regulated under WAC Title 222, except for Class IV General Forest Practices that are conversions from timberland to other uses;
  • Actions by a public utility or any other government agency to remove or alleviate an emergency condition, restore utility service, or reopen a public thoroughfare to traffic;
  • Land divisions, interior improvements to an existing structure, and other activities requiring permits or approvals for which there is no physical disturbance to the surface of the land; and,
  • Minor land-disturbing activities that do not require a permit.

Although an ESC plan may not be required for the situations noted above, that does not relieve the proponent from the responsibility of controlling erosion and sediment during construction nor the liability of damage claims associated with adverse impacts on off-site properties.