Stormwater rules on way

New rules to reduce stormwater runoff from construction sites and development projects are about to be unveiled in Olympia, Lacey, Tumwater and Thurston County.

The four jurisdictions are among 85 smaller counties and cities in Western Washington required under the federal Clean Water Act to improve their stormwater controls by August.

For Thurston County, Lacey and Tumwater, it is the first major overhaul of stormwater and erosion control requirements on projects larger than 1 acre in 15 years. Olympia upgraded its stormwater manual in 2005.

On the environmental front, the changes should increase the amount of stormwater treated and infiltrated into the site, and reduce the amount and velocity of stormwater discharged to area rivers, streams, lakes and Puget Sound, leading to an improvement in water quality and stream health.

Stormwater runoff has been identified as the leading cause of pollution for Puget Sound in urban areas, according to the state Department of Ecology.

On the development front, the new rules are likely to add to the cost of development and reduce the amount of buildable land in urban Thurston County, said Will Stakelin, director of government affairs for the Olympia Master Builders.

“We want to effectively manage stormwater, but expanded regulations can reduce our ability to develop land,” he said.

Thurston County and Olympia will roll out their draft stormwater manuals for formal public review next week, while Lacey and Tumwater are shooting for June.


The new rules are an opportunity for the cities and the county to start requiring and promoting low-impact development – a set of techniques to control stormwater, including rain gardens, use of pervious surfaces that can soak up rainwater, collection and reuse of rainwater from rooftops, and increased protection of vegetative cover and native soils on development sites.

“It’s a no-brainer, it’s reasonable and it can be done,” said Bruce Wishart of the conservation group People for Puget Sound. “These cities should be moving to LID now, not later.”

In a February ruling, the state Pollution Control Hearings Board directed Ecology, which manages and regulates the stormwater permits for the federal government, to start moving the smaller cities and counties toward greater use of LID practices where it is feasible as an anti-pollution approach to development. The larger jurisdictions in the Puget Sound region, including Seattle and Tacoma, already have been directed to embrace LID practices.


While the real push to require smaller cities and counties to use LID practices will occur when the rules are revised again in 2012, some here in South Sound are moving in that direction sooner, rather than later.

“One of the first priorities in our new stormwater manual is to use LID techniques to the maximum extent that’s practical,” county stormwater engineer Pat Allen said.

“Our primary goal is to infiltrate as much stormwater on site as possible,” said Doug Christensen, Lacey water resources engineer. “We’re not requiring developers to use an LID approach, but we are directing them to at least consider it.”

A low-impact development approach to stormwater is gaining momentum, much like green building techniques started slowly but grew in popularity over the past several years, noted Bruce Wulkan, stormwater program manager for the Puget Sound Partnership.

Here are some of the other changes in stormwater management likely from the new regulations:

 • The city of Olympia will require increased treatment of stormwater before it is infiltrated into the ground in its wellhead protection areas to keep pollution from entering drinking water supplies, Olympia water resources engineer Craig Tosomeen said.

 • The Olympia manual will limit stormwater pond retaining walls, encourage more stormwater pond landscaping, and reduce stormwater pond slopes to keep them from looking so sterile, Tosomeen said.

 • Thurston County will require different stormwater designs ranging from straightforward to complex, depending on the environmental sensitivity of the site.

“It means more people will probably have to hire civil engineers to design their stormwater controls,” Allen said.

John Dodge: 360-754-5444



Thurston County and Olympia will conduct open houses beginning next week to discuss proposed rules to manage stormwater runoff from development projects.

The updated drainage and erosion-control practices are required to meet statewide standards set by the Department of Ecology.

The goal is to reduce pollution and erosion caused by stormwater entering rivers, streams, Puget Sound and groundwater.

The Thurston County meetings, all from 6:30 to 8:30 p.m.:

Thursday in Building 1, Room 280 in the Thurston County Courthouse, 2000 Lakeridge Drive S.W., Olympia.

June 2 at the Thurston County Fairgrounds Heritage Hall, 3054 Carpenter Road S.W., near Lacey.

June 4 at Parkside Elementary School, 301 Central Ave. E., Tenino.

The Olympia meeting is set for 4 to 6 p.m. Tuesday at the Smith building, 837 Seventh Ave. S.E., Olympia.

For more information on the revised rules, go to www.olympiawa.gov/cityutilities or www.co.thurston.wa.us/stormwater.