Stormwater - LID Code Integration


Integrating Stormwater Best Management Practices into Thurston County Code


New Stormwater Standards Underway

Thurston County is among many counties and cities required to make “Low-Impact Development,” or LID, the preferred and commonly used approach to site development. LID is a stormwater management strategy that is designed to minimize impervious surfaces, maximize native vegetation retention, and filter stormwater on site as much as possible. 

Regulatory Framework for Updating Codes

In mid-2014, TRPC began helping Thurston County review its codes, plans and standards and consider ways to encourage LID practices, per the Phase II Western Washington Municipal Stormwater Permit requirement to make LID the “preferred and commonly used approach to site development.”

The project team, led by a workgroup of County staff engineers and other technical experts, is meeting monthly and following the approach detailed in the Puget Sound Partnership’s 2012 publication, Integrating LID into Local Codes: A Guidebook for Local Governments. 

The project team gathered input from several other workgroups and broader public outreach efforts through 2015 and drafted code and plan revisions for policymaker consideration in 2016. 

Stormwater Cycle

The primary stormwater management objective of LID is to approximate pre-development (native) forest conditions (or prairie condition if historic records indicate that as the native setting) over the full range of rainfall intensities and durations.

Pollution Challenges

When it rains in the Pacific Northwest, much of the stormwater flows via pavement and pipes into our waterways, picking up petroleum and other pollutants along the way.

Current conventional land use and development patterns, building construction techniques, and stormwater treatment facilities are insufficient to protect the long-term ecological functions of our natural resources and water bodies.

Hydrologists, biologists, architects, and stormwater management professionals are continually improving their understanding of stormwater science and management practices. Practices are routinely revised and adapted to minimize the impacts of the built environment on the natural environment. Laws and regulations are revised accordingly to reinforce the use of best management practices that are believed to offer solutions to complicated problems.




Stormwater pollution is the leading cause of impairment to  our creeks, rivers, lakes, groundwater, and the Puget Sound.

Contact Us

  1. For more information about this planning process, contact:

    Mike Burnham, Associate Planner

    Thurston County
    Allison Osterberg, Associate Planner
    360-754-3355, x7011