Action 9: Reduce Impervious Surfaces and Increase Green Stormwater Infrastructure Solutions
   

As populations grow in cities and towns, the amount of impervious surface tends to increase, as does the presence of contaminants from industry, transportation and other human impacts on the landscape. This is a critical issue, especially as contaminants in urban streams contribute significantly to the health of salmon, especially coho. Contaminants from car tire particles lead to “pre-spawn mortality” for coho, meaning they are killed before being able to spawn (Pearsall et al 2021). Managing stormwater runoff through green stormwater infrastructure is an important part of the solution, and provides benefits for people, salmon and other wildlife.
 
Outcome 19: Expand green stormwater infrastructure programs, including the development of at least $50M worth of prioritized projects and an expansion of workforce training opportunities, by 2025.
Outcome 20: Mobilize 50,000 hours of Urban Forestry Revitalization workforce training and Corps crews work time by 2024 and sustain at least 14,000 hours of crew work time and training annually.
Outcome 21: Reduce impervious surface levels in key urban sub-basins to below 30% by 2031.
 

0-3 Year Actions

 

Action 9.1 Urban Forestry Revitalization Corps 

Establish an Urban Forestry Revitalization Corps program to implement projects that increase green stormwater infrastructure solutions and increase urban forest canopy cover. This may involve utilizing the Puget SoundCorps program, and may expand to meet additional needs outlined in this plan or to connect to Civilian Climate Corps efforts.

Action 9.2 Water Quality Screening Study

Conduct Water Quality Screening Study to identify interventions with highest return on investment in WRIA 7 key urban areas. Assess the most significant contamination sources such as specific roads or bridges.

Action 9.3 Tree Interception Effectiveness Study

Participate in an Effectiveness Study of Tree Interception and Management of Water with Washington State University and The Evergreen State College.others to determine priority geographic area.

Action 9.4 Nonpoint Source Pollution

Work with Tulalip Tribes on Visualizing Ecosystem Land Management Assessments (VELMA) tool to evaluate natural and engineered opportunities to address nonpoint sources of pollution.

 

4-10 Year Actions

Action 9.5 Green Stormwater Infrastructure

Use water quality and related research to complete a prioritized water quality and green stormwater infrastructure project list for targeted urban area(s). Develop at least $50M worth of prioritized projects, and develop funding and implementation strategy, by 2025.

Action 9.6 GREEN STORMWATER INFRASTRUCTURE PARTNERSHIPS 

Develop comprehensive green stormwater infrastructure public-private partnership(s) in the Snohomish Watershed. Work with local government, private sector, nonprofit and environmental justice partners to develop vision and roles. Utilize Urban Forestry Revitalization crews where appropriate. Track urban greening and depaving outcomes to contribute to reducing urban impervious surface levels below 30% by 2031.

Action 9.7 GREENING INCENTIVES 

Establish mechanisms to incentivize private greening activities by partnering with regulatory agencies and larger municipalities within the WRIA. Potential models for consideration include: Washington DC’s Stormwater Retention Credit Trading Program; City of Philadelphia’s Green City, Clean Waters Initiative. May involve establishing a stormwater credit trading program.

Action 9.8 GREEN Campuses 

Work in partnership with private sector entities to green corporate campuses. Attention should be paid to improving human health and environmental justice in this work. Utilize Urban Forestry Revitalization crews where appropriate. 

Action 9.9 DNR Facilities 

Retrofit priority DNR facilities in WRIA 7 with low-impact development and green stormwater infrastructure by 2031.