Hide Alert

Welcome to our new website. Learn more about what's new.

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 trainings for a variety of professional audiences. We partnered with Washington State University to develop a joint Washington State LID Certificate Program.

Over the spring and summer of 2017, the certificate program will be transitioning from an exclusively in-person training to a hybrid online and in-person system.

The program offers two certificate tracks:

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

Planning and code update information

Maintenance and inspection resources