TagInterlocal Agreement(74)

Four cities near Sea-Tac Airport — Burien, Des Moines, Normandy Park, and SeaTac — have joined together under a formal interlocal agreement to coordinate their review of the Port of Seattle's Sustainable Airport Master Plan (SAMP), which could bring significant noise and environmental impacts to surrounding communities over the next 20 years. The agreement establishes a shared process for hiring consultants, submitting joint public comments, and responding to environmental documents produced under federal (NEPA) and state (SEPA) law. The collaboration is set to run through December 31, 2027, with the City of Des Moines managing consultant contracts and the City of Burien overseeing fiscal matters.

The cities of Burien, Des Moines, Normandy Park, and SeaTac are renewing a cooperative agreement to jointly review and respond to the Port of Seattle's Sea-Tac Airport Sustainable Airport Master Plan (SAMP), which outlines future airport growth that could significantly impact neighboring communities. The new Interlocal Agreement (ILA), approved by Des Moines City Council in December 2024, extends collaboration through December 31, 2027, allowing the cities to share consultants and coordinate formal comments on the airport's environmental review process under NEPA and SEPA. Des Moines has committed up to $74,170 toward consultant services, with each city's share determined by relative population.

The Normandy Park City Council's December 10, 2024 agenda includes renewal of a lapsed Interlocal Agreement (ILA) among four cities — Normandy Park, Des Moines, Burien, and SeaTac — formed to coordinate review of the Port of Seattle's Sustainable Airport Master Plan (SAMP) and its environmental impacts. The renewed agreement removes a fixed expiration date, instead allowing the partnership to continue until the SAMP environmental review process is fully complete. Normandy Park contributes 5.6% of shared costs and has participated in the collaborative effort since the ILA's original adoption in March 2018.

This interlocal agreement between the Washington State Department of Transportation (WSDOT) and the City of SeaTac outlines a cooperative arrangement for road improvements on S. 204th Street between 32nd and 34th Avenues South, as part of the SR 509 Completion Project near Sea-Tac International Airport. WSDOT agreed to assign the construction work in that corridor to the City of SeaTac and reimburse the city up to $1,641,318 upon substantial completion. After construction, the City of SeaTac is responsible for maintaining all improvements, including sidewalks, lighting, and stormwater facilities.

The Des Moines Creek Basin Restoration Projects Interlocal Agreement (GCA-3921) is a cooperative agreement between the City of Des Moines, City of SeaTac, Port of Seattle, Washington State Department of Transportation, and King County to fund and manage several creek restoration projects. The projects aim to control stream flows, improve water quality and fish habitat, and address drainage and flooding problems in the Des Moines Creek Basin. The agreement also serves as part of the stormwater management strategy for the SR 509 highway extension, with costs and responsibilities shared among the participating agencies.

This interlocal agreement establishes a cooperative framework between King County, the City of Des Moines, the City of SeaTac, WSDOT, and the Port of Seattle to implement the Des Moines Creek Basin Plan. The parties agreed to jointly fund and manage the preparation of a Final Design Report, Financing Plan, and environmental permits for capital projects addressing stormwater runoff, flooding, fish habitat, and water quality in the Des Moines Creek Basin. WSDOT's participation was motivated in part by the need to reduce the impacts of surface water runoff from State Routes 509 and 99 and Interstate 5 on the surrounding natural resource system.

This Land Use Technical Report, prepared by Landrum & Brown for the Port of Seattle in January 2024, examines how near-term construction projects outlined in the Seattle-Tacoma International Airport Sustainable Airport Master Plan align with existing and planned land use regulations in surrounding communities. The report reviews local plans from cities including SeaTac, Des Moines, Burien, and Tukwila, as well as a 2018 Interlocal Agreement between the Port and the City of SeaTac, to assess potential land use impacts of the proposed airport expansion alternatives. It concludes by evaluating the consistency of the proposed action and a hybrid terminal option with applicable local and regional planning policies.

This April 2023 presentation by Erin Nelson outlines options for the Des Moines Creek Basin Committee as it prepares to renew its Interlocal Agreement (ILA), a cooperative arrangement among local jurisdictions managing the creek basin near Des Moines, Washington. The meeting agenda covers a review of past studies and committee accomplishments, a discussion of what has worked and what needs improvement, and a decision on workable paths forward. While focused on stormwater and creek basin management rather than airport noise policy directly, the Des Moines Creek basin is located adjacent to Sea-Tac Airport and its management is relevant to the broader environmental context of the surrounding area.