Pierce County Planning & Public Works (PPW) has been awarded a $500,000 grant to help advance eelgrass monitoring along Pierce County shorelines. Eelgrass (Zostera marina) is a primary indicator of ecosystem health for the Puget Sound’s marine nearshore habitat because it sustains diverse food webs, creates complex habitat for fish and wildlife, and is highly sensitive to human impacts.
Starting this summer, PPW and the Washington State Department of Natural Resources (DNR) will collect data on marine vegetation by using underwater videography at approximately 180 Pierce County sites. The results will be analyzed to identify the distribution of eelgrass beds in the county’s nearshore environment.
Mapping this vulnerable resource will contribute to an upcoming update of Pierce County’s Shoreline Master Program, which is scheduled to be completed in 2029. This project also fulfills an action outlined in the county’s Sustainability 2030 Plan, which seeks to reduce Pierce County’s greenhouse gas emissions.
This Environmental Protection Agency (EPA) funding comes from a Puget Sound National Estuary Program Habitat Strategic Initiative Lead (HSIL) grant to advance strategies that improve the health of shorelines and estuaries in the Puget Sound. The data will be used to advance the efforts of the Washington State DNR Nearshore Habitat Eelgrass Monitoring Program, assist local tribes and organizations working to support salmon and shellfish recovery, and protect vulnerable habitat critical to marine diversity in the South Puget Sound.
What is Eelgrass?
Eelgrass (Zostera marina) is a flowering plant typically found in muddy or sandy shallow tidal areas of the Puget Sound. It grows in underwater meadows that provide habitat for a range of organisms and perform many functions for the South Puget Sound. Eelgrass is sensitive to human impacts, so its health can reflect the state of ecosystems in nearshore habitat in marine areas. Along with its ability to sequester carbon, eelgrass meadows provide habitat for young forage fish that nourish our native salmon populations.
Shoreline Master Program
The Washington State Shoreline Management Act (SMA) requires that Pierce County, along with other jurisdictions, maintain a Shoreline Master Program for the purpose of guiding activity along the state’s shoreline areas. Pierce County’s Shoreline Master Program (SMP) is a set of local regulations that guide the use of state shorelines that are within county boundaries. These shorelines are valuable in multiple ways: ecologically, culturally, economically, and socially. Both the shoreline and nearshore environments provide recreational opportunities and rich habitat for fish and wildlife.
Sustainability 2030 Plan
The Sustainability 2030 Plan aligns with the State of Washington’s climate commitments and seeks to reduce climate change-causing greenhouse gas (GHG) emissions 45% by 2030 based on a 2015 baseline. The Sustainability 2030 Plan provides a road map of measurable and science-based actions for reducing communitywide emissions and Pierce County’s internal operational emissions.
Using herbicides on lawns can indirectly kill eelgrass (Zostera marina) and other aquatic vegetation. When herbicides run off into waterways, they can disrupt aquatic ecosystems by harming eelgrass, which is vital for marine habitats. Eelgrass provides oxygen, stabilizes sediment, and serves as a nursery for many marine species.
Common lawn herbicides like glyphosate and 2,4-D can be particularly harmful. Even if they don’t target eelgrass directly, they can reduce water quality, leading to algal blooms that block sunlight and deplete oxygen, effectively killing eelgrass. To protect eelgrass, it’s best to use eco-friendly lawn care practices, like minimizing chemical use, planting native vegetation, and ensuring proper drainage to prevent runoff.