Submitted by San Juan County.
The False Bay watershed on San Juan Island, with its wetland habitats, agricultural uses and impact on water quality, has been a high priority watershed for the County for several years. The False Bay corridor, including Zylstra Lake, continues to be an important part of the County’s restoration efforts with the Department of Environmental Stewardship and Conservation Land Bank collaborating on revegetation work that benefits water quality, wildlife and agriculture. None of the restoration work includes dam removal.
Current Restoration Efforts
Restoring the False Bay watershed has been identified in numerous iterations of the County’s Capital Improvement Program. This year, the County received Salmon Recovery and Washington state Department of Ecology grant funding to restore the area below the dams and determine ways to reduce the “heat sink” in the lower, smaller lake. Shallow lakes like that are susceptible to warming, which can result in harmful algae blooms – something that occurred in the lake in 2021.
Current restoration work includes replacing invasive species with native vegetation, fencing livestock away from the creek, and shading areas of the lakes and streams to reduce water temperature. Through these efforts, the County hopes to preserve Zylstra Lake’s ability to serve as vibrant wildlife habitat, maintain a healthy water quality and support agricultural land with irrigation needs.
“We’re working to restore the watershed for public health and safety, water quality and agricultural use benefits,” says Environmental Stewardship Director Kendra Smith. “If you have a toxic algae bloom, it impacts the entire food chain including those who use the water for irrigation. The water from the lakes flows down to the False Bay Preserve where people and pets also have contact with the water, and we want them to be safe.”
This revegetation work has been ongoing along the stream corridor for more than five years and will continue until canopy cover is well established along the stream and edges of the lake and wetlands of the lower lake.
Dam Removal
San Juan County and the Conservation Land Bank do not have plans to remove the dams at Zylstra Lake. During a meeting of the Clean Water Advisory Committee in 2022, County staff provided an update on ongoing wetland restoration work in the False Bay watershed. This update included a discussion about the dams at Zylstra Lake and their impact on salmon habitat. The Land Bank Commission did not engage further with the conversation of removing the dams and does not have plans to pursue this idea. The upper lake of the Zylstra Lake Preserve provides great ecological, agricultural and recreational value, and the dam supporting it was recently repaired and strengthened. Any future dam work will require further analysis and approval by the Land Bank Commission, as well as public engagement.
What’s Next?
The Land Bank is currently working on its long-term management plan for the Zylstra Lake Preserve. This work will include extensive opportunities for public participation.
Do you have additional questions about the Land Bank and its preserves? Join a countywide public meeting on Thursday, Oct. 24, from 6-7:30 p.m. The meeting will begin with a brief organizational update from staff followed by an open Q&A.
Register here to join the meeting: https://us06web.zoom.us/meeting/register/tZUqf-ippjgqG9DMQc5DC8x04cx2-8RkYFqu#/registration.
