TagInterlocal Agreement(74)

The cities of Burien, Des Moines, Normandy Park, and SeaTac have entered into a formal interlocal agreement to coordinate their review of, and potential legal challenges to, the Port of Seattle's Sustainable Airport Master Plan, which could bring significant growth and environmental impacts to their communities over the next 20 years. Under the agreement, the four cities will jointly hire environmental consultants and legal counsel, share costs proportionally based on population, and issue unified comment letters during the NEPA and SEPA review processes. The City of SeaTac is designated as the lead administrator for contracts and finances, while all four cities must unanimously agree before filing any joint legal appeal.

This interlocal agreement between the City of SeaTac and the City of Burien outlines roles, responsibilities, and cost-sharing for the Miller Creek Stream Realignment and Daylighting Project, which will improve fish passage and replace an aging culvert under Des Moines Memorial Drive. Burien will design and construct the project, while SeaTac agrees to reimburse Burien up to $985,000 for work performed within SeaTac's right of way. SeaTac retains inspection and approval rights over all construction elements within its jurisdiction.

The City of Des Moines and neighboring cities have entered into an Interlocal Agreement (ILA) to coordinate their review of and response to the SeaTac Airport Master Plan (SAMP) environmental review process, covering both federal (NEPA) and state (SEPA) requirements. Originally signed in 2018 and updated in 2024, the agreement establishes how participating cities share costs, manage contracts, and jointly hire environmental and legal consultants—including attorneys who can support a legal challenge to the SAMP's environmental conclusions. The latest version, managed by the City of SeaTac and expected to run through December 31, 2028, excludes Normandy Park but otherwise continues the multi-city partnership focused on protecting community interests during the airport planning process.

The cities of Burien, Des Moines, and SeaTac are joining forces under a formal Interlocal Agreement to coordinate their review of and legal response to the Port of Seattle's Sea-Tac Airport Sustainable Airport Master Plan (SAMP), which could bring significant noise and environmental impacts to surrounding communities. The agreement, considered by Des Moines City Council on November 13, 2025, allows the three cities to jointly hire environmental consultants and legal counsel to analyze and formally challenge the airport expansion's environmental review under both federal (NEPA) and state (SEPA) law. A Draft Environmental Impact Statement from the Port is expected in early 2026, with the overall process estimated to conclude by December 31, 2028.

The SeaTac City Council is considering an ordinance to hire outside legal counsel and update a cost-sharing agreement with the cities of Burien, Normandy Park, and Des Moines to challenge or engage with the FAA's environmental review of Seattle-Tacoma International Airport expansion plans. The four cities would jointly retain two law firms—Leech Tishman for federal NEPA matters and Ogden Murphy Wallace for state SEPA matters—at an estimated cost of $350,000, with SeaTac covering roughly 26% and recovering the rest from its partner cities. The effort is driven by the FAA's September 2025 issuance of a Final Environmental Assessment and Finding of No Significant Impact, which must be challenged by November 25, 2025.