Low Impact Development (LID) guidance

Low Impact Development (LID) is a stormwater and land-use management strategy that tries to mimic natural hydrologic conditions by emphasizing the following techniques:

• Conservation
• Use of on-site natural features
• Site planning
• Distributed stormwater best management practices (BMPs) integrated into a project design

LID best management practices emphasize pre-disturbance hydrologic processes of infiltration, filtration, storage, evaporation, and transpiration. Common LID practices include: bio-retention, rain gardens, permeable pavements, minimal excavation foundations, vegetated roofs, and rainwater harvesting.

Want to be certified in LID?

We received two years of funding from the Legislature to develop and provide several topic-based Low Impact Development training courses for a variety of professional audiences. We partnered with Washington State University to develop a joint Washington State LID Certificate Program.

The program offers two certificate tracks:

• Low Impact Development operations and maintenance
• Low Impact Development design

Planning and code update information

• LID Code Update and Integration Toolkit
• LID Briefings for Elected Officials - Eastern Washington Presentation
• LID Briefings for Elected Officials - Western Washington Presentation
• Association of Washington Cities (AWC) LID web page
• EPA LID "Barrier Busters" Fact Sheets

Maintenance and inspection resources

• Western Washington LID Operations & Maintenance (O&M) Guidance Document
• Presentation on the LID O&M Guidance Document
• Example Bioretention Inspection Form
• Example Permeable Pavement Inspection Form

Related links

• Association of Washington Cities (AWC) LID
• Building Industry Association of Washington (BIAW) LID
• Washington Association of Landscape Professionals (WALP)
• Washington State Nursery & Landscape Association (WSNLA)

Contact information

Douglas C. Howie, P.E.
Senior Stormwater Engineer
douglas.howie@ecy.wa.gov
360-870-0983