Commission hears Lake Sammamish management-plan update emphasizing restoration and constraints on new development

State Parks staff told the Parks and Recreation Commission that Lake Sammamish State Park remains a regionally significant natural area that receives about 2 million visits a year and that new development proposals must be weighed against wetlands, mitigation costs and the park's role in regional stormwater and biodiversity resilience.

Planning manager Michael Hankinson and staff gave commissioners an overview of the park’s natural systems, ongoing restoration and the 2007 Commission vision that the park be "Washington's signature park for protecting and celebrating urban natural areas." Staff said the park covers about 524 acres, roughly 30% of which is developed; it includes more than 6,800 feet of shoreline, three creeks (Issaquah, Laffing Jacobs and Tibbetts), more than 400 acres of wetlands or wetland buffer, nine boat-launch ramps and about 2,200 parking stalls.

Hankinson summarized restoration and community investments since 2007: staff reported roughly 62 acres restored since 2007, about 65,000 native trees and shrubs planted with the help of approximately 20,000 volunteers, 85,800 volunteer hours valued at about $1.7 million in-kind, and more than $5.5 million in grants and financial support from partners, cities, King County, state and federal sources. Staff said partners such as Mountains to Sound Greenway Trust and Trout Unlimited have led stewardship and restoration projects, including work to realign Laffing Jacobs Creek to aid salmon recovery.

The commission was told that several proposed developments evaluated in a 2018 update—most notably a large multi-sport complex—are sited in wetlands or buffers and would carry very high mitigation costs. Staff cited a high-level estimate that mitigation alone for a multi-sport athletic field complex would approach $50 million (not including capital construction costs). Because of wetlands extent and associated mitigation expense, staff recommended shifting from a full master-plan update toward an updated management plan (a narrower, more action-oriented document) with clearer criteria for vetting future proposals.

Staff emphasized the park’s role in urban stormwater management and biodiversity: Lake Sammamish State Park acts as a receiving area for watershed stormwater and conveys floodwaters to the lake; mapping from The Nature Conservancy indicates the park as a relatively resilient land patch that supports regional biodiversity and provides critical habitat links to Cougar Mountain. Staff also noted kokanee salmon numbers have fallen sharply since 2007, with returning spawners dipping below 150 fish eight different years, and said park-led habitat work could play a role in recovery efforts.

City and partner coordination was highlighted: staff said the City of Issaquah would likely pursue smaller-scale organized-sports proposals if it brings formal proposals and that the commission’s 2007 policy directs that no additional state park lands be dedicated for athletic fields for scheduled athletic use, while allowing existing facilities and partnerships to continue under current leases (the soccer club lease runs through 2029). Staff said the commission will expect proposers to carry mitigation and analysis costs and that any field lighting, artificial turf or permanent seating would require commission approval.

Moving forward, staff said they will produce an updated management plan with clearer criteria and a path for evaluating proposals, including universal-access and equity goals, greater tribal engagement on kokanee recovery and options for reducing parking footprints to lessen ecological impact. Staff said they will convene partner work groups and present a more detailed management-plan schedule later in the year.