skip general nav links ACHP home About ACHP


National Historic

Working with
Section 106

Federal, State, & Tribal Programs

Training & Education


 skip specific nav links
Home arrow Historic Preservation Programs & Officers arrow Federal arrow FHWA

Case Study - Washington State

Despite controversy, Programmatic Agreement signed for State Route 520 widening and bridge replacement project, Interstate 5 to Medina

Description of the Project:

The Washington Department of Transportation (WSDOT) and Federal Highway Administration (FHWA) propose to replace the aging Evergreen Point Bridge and expand State Route (SR) 520 to include six new traffic lanes over a 12.8 mile corridor from Interstate 5 in Seattle to SR 202 in Redmond. The purpose of the overall project is to enhance safety by replacing the deteriorating floating bridge that carries traffic over Lake Washington and to improve traffic flow through the heavily congested The high section of the bridge from the west (zoom)corridor. Although the project will have many benefits, such as landscaped lids that will reconnect historic neighborhoods that were bisected by original construction of SR 520, the proposed project will have an overall adverse effect on historic properties.

Due to the complexity of the project, its location in a residential urban corridor, and its long construction period, the project will have direct, indirect and cumulative effects on a variety of historic properties. The new bridge over Portage Bay will be higher and wider than the current structure, and will alter the view from historic residential and non-residential properties adjacent to the bay.  Construction of the new bridges and highway widening will occur over a period of seven years, beginning in 2012, and will likely result in increased noise, dust, and traffic, visual effects, and disruptions in access to areas near construction sites. To resolve these effects, WSDOT developed, in consultation with affected parties, a Programmatic Agreement (PA) that includes measures to minimize or mitigate effects on historic properties; and requires WSDOT to develop a Community Construction Mitigation Plan that contains specific measures designed to protect historic buildings and address quality of life issues. Many local residents are represented by consulting parties. The PA was executed on June 7, 2011.

Who Participated in Consultation?

The project is located within lands and waters formerly occupied by Lakes Duwamish Indians, whose descendents are enrolled into several federally recognized Indian tribes, including the Muckleshoot Indian Tribe, Suquamish Tribe, Snoqualmie Tribe, the Tulalip Tribes and the Yakama Nation, as well as the non-federally recognized Duwamish Tribal Services. Foster Island is part of the historic Washington Park Arboretum, and a property of cultural and religious significance to Indian tribes. FHWA and WSDOT worked closely with the tribes to identify the project’s effects on traditional practices and archaeological remains associated with Foster Island, and to find measures to resolve effects.

In addition to the ACHP, State Historic Preservation Officer (SHPO), WSDOT, and FHWA, consulting parties included: the City of Seattle, Concerned Citizens of Montlake - SR520, Friends of Seattle's Olmsted Parks, the Historic Bridge Foundation, Historic Seattle Preservation Foundation, King County Historic Preservation, Montlake Community Club, NOAA, North Capitol Hill Neighborhood Association, Portage Bay/Roanoke Community Council, Saint Demetrios Greek Orthodox Church, Seattle Yacht Club, University to Washington, Washington Park Arboretum Foundation, Washington Trust for Historic Preservation, the Madison Park Community Council, and the Indian tribes identified above.

Why was ACHP Involvement Needed for this Case?

A total of 345 historic properties have been identified in the project Area of Potential Effects (APE). These include the Evergreen Point Bridge, the longest floating bridge in the world, two historic districts, the contributing elements to the districts, an Olmstead Brothers designed park and parkway, several individual properties eligible for or listed in the NRHP, and Foster Island.  FHWA and WSDOT initiated Section 106 consultation with the SHPO on the I-5 to Medina project in 2009. The ACHP elected to participate in consultation in July 2010. ACHP’s decision to participate was based on the large number of historic properties affected, the project’s complexity, and substantial public interest in the effects of the project on historic properties.

Analysis of Consultation and Agreement:

Evergreen Point Bridge on SR 520 WestIn addition to the Evergreen Point Floating Bridge, which will be demolished and replaced, the project will affect the Montlake Historic District, the Roanoke Park Historic District, individually eligible residential properties, the Seattle Yacht Club, the Montlake Bascule Bridge, Lake Washington Boulevard, the Washington Park Arboretum, and other properties of historic significance. Because of the impact this highway project would have on adjacent communities; WSDOT designed the preferred alternative to include two landscaped lids over SR 520 that will reconnect historic neighborhoods bisected by SR520, and will reconstruct interchanges to improve functionality. Additionally, WSDOT is committed to a Context-Sensitive Solutions approach to replacement of the Portage Bay Bridge and the new Bascule Bridge on Montlake Boulevard, where the existing historic Bascule Bridge will rehabilitated for continued use.   

Consultation has been difficult due to the size and complexity of the proposed project and the nature of the effects to historic properties.  The APE included some 345 historic properties and was addressed in early consultation among stakeholders, however, not to everyone’s satisfaction. Residents remain concerned about the quality of life in waterfront neighborhoods, including noise, pollution, vibrations, and changes to existing views of Portage Bay and Lake Washington. Particularly difficult to address in the Section 106 process is the range of potential effects due to noise, vibrations, and potential changes in air quality; both during construction and during operation of the new bridges and widened interstate highway.  Residents and property owners in the Montlake Historic District are particularly concerned that the use of proposed haul routes and the installation of new bridge piers will create vibrations that could permanently damage adjacent historic  homes.

To address these concerns, WSDOT and FHWA have developed a PA that requires specific mitigation to address many of the consulting parties’ issues, and takes an adaptive approach to resolving construction impacts, or potential construction impacts with community input as construction proceeds from 2012 to 2018. The PA includes a great deal of specific mitigation for the effects of the project on historic properties, and ongoing consultation among the consulting parties, who have been invited to concur in the PA.  Read the full Programmatic Agreement Here. (Read the PA appendices here.) Highlights include requirements that FHWA and WSDOT:

  • Develop and implement a comprehensive treatment plan for the Foster Island TCP in consultation with affected tribes, the Corps of Engineers, SHPO and the ACHP;
  • Conduct archaeological data recovery where subsurface archaeological properties cannot be avoided;
  • Reconstruct the SR 520 / Montlake Boulevard interchange following the City of Seattle Olmsted Park Furniture Standards and the Secretary of the Interior’s standards for rehabilitation;
  • Prepare a NRHP Multiple Property Documentation form for Seattle’s Olmsted-designed parks and boulevards and an associated nomination form for Lake Washington Boulevard;
  • Create a landscape design plan for the Montlake and Roanoke lids that are compatible with the historic character of the Montlake and Roanoke Park Historic District and includes interpretive exhibits and markers;
  • Complete a Community Construction Management Plan in consultation with the consulting parties and local communities to ensure that construction impacts such as noise, lighting and glare, and vibrations are minimized and monitored throughout construction;
  • Document the Evergreen Point Bridge to HAER Level II standards, place the documentation in appropriate repositories, and include a summary on WSDOT’s interpretive website.

Through the course of consultation, the ACHP was called on to assist with resolving disputes among consulting parties regarding the sufficiency of WSDOT’s and FHWA’s efforts in following the steps of the Section 106 review process. WSDOT also engaged a qualified consultant to work as a liaison to consulting parties in the development of the PA. However, the ACHP’s role as the authority on the requirements of Section 106 was important to informing the parties of their legal roles and responsibilities and keeping the Section 106 consultation moving forward on this large and very complex project.

Why This is a Good Agreement:

FHWA and WSDOT have done an excellent job of consulting, working with a large, complex project and a deeply concerned and unwieldy group of consulting parties. While the massive project understandably remains a concern to many residents in adjacent historic districts, FHWA has made every effort to address their concerns, and put together a mitigation package that should serve well to minimize and mitigate the effects of the project on historic properties.Bicyclist on the old Montlake Bridge The agreement went through several iterations, but the final, signed PA is well organized and thorough and reflects a commitment to minimizing damage to historic properties and the disruption to the adjacent communities.  In addition to the many specific mitigation measures agreed to, of particular note is the commitment to develop a Community Construction Management Plan that provides consulting parties and other members of the affected communities to have an active ongoing role in monitoring and managing construction impacts to the historic neighborhoods.  Although it is difficult to distinguish adverse effects to historic properties from generalized community impacts, the CCMP allows coverage for all nature of effects, including those that may impact historic properties.  

For more information please contact Carol Legard, FHWA Liaison, at

Updated June 13, 2011

Return to Top