The Science of LID: Washington Stormwater Center Dedication

SvR’s Peg Staeheli, Kathy Gwilym, and Nate Cormier attended the dedication of the Washington Stormwater Center, formerly the Washington State University-Puyallup LID Research Center, on March 20, 2011. SvR worked with leading soil, plant, and hydrology researchers to design and engineer this pioneering research facility. The Center’s “designed experiments” include:

  • a parking lot with test cells to evaluate flow control and water quality performance of porous asphalt and pervious concrete
  • a grid of rain gardens comparing the water quality and flow control performance of various plant palettes and maintenance regimes
  • a gallery of soil mesocosms comparing the performance of various soil mixtures

Taken together, these LID stormwater features will allow in-depth and long-term research into the effectiveness of green stormwater infrastructure, providing relevant, high-quality data that will help improve policy and design. The event included speeches by Congressman Norm Dicks, WSU President Elson Floyd, and EPA Regional Director Dennis McLerran, among others. The event also celebrated the announcement of the Center as the Pacific Northwest location for the EPA’s Green Infrastructure Partnership, a program to disseminate leading research and technical information nationwide.

You can learn more about the Center at:



Bellevue's Natural Drainage Maintenance Guidelines Posted

by Kathy Gwilym City of Bellevue recently posted their new Standard Details and Storm and Surface Water Maintenance Standards manual.  In the Storm and Surface Water Maintenance Standards manual, maintenance guidelines for natural drainage practices such as rain gardens/bioretention systems, green roofs, permeable pavements, etc have been incorporated.  SvR’s development of maintenance guidelines for natural drainage practices (NDP) for Bellevue’s Utilities Department was funded through a grant from King County Conservation District.  A copy of the maintenance guidelines for Bellevue’s NDP/Green Stormwater Infrastructure/LID elements along with sample maintenance inspection checklists can be found on our resources page and on City of Bellevue’s website, here and here.

High Point Landscape Maintenance Guidelines Updated

After designing the natural drainage systems and other landscape enhancements along the street corridors in Seattle’s High Point community, the Seattle Housing Authority asked us to provide a year-round maintenance manual to assist the landscape and open space management team with keeping the green infrastructure systems working optimally. As we've noted before, often times concerns about maintenance can be a barrier for developers who want to implement green infrastructure solutions like additional plants, amended soils and porous pavements, so these types of maintenance manuals can critically important to getting assurance that the landscape can be cared for over time.

Read More