TO: Mayor and City Council
THROUGH: Krishna Namburi, Interim City Manager
FROM: Brian D. Martin, Public Works Director
SUBJECT:
title
Section 4(f) De Minimis Concurrence - Center Street Bridge Seismic Retrofit Project
Ward(s): All Wards
Councilor(s): All Councilors
Neighborhood(s): All Neighborhoods
Result Area(s): Safe, Reliable and Efficient Infrastructure; Welcoming and Livable Community.
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SUMMARY:
summary
The Oregon Department of Transportation (ODOT) is advancing Phase 1 of the Center Street Bridge Seismic Retrofit Project. As part of the federal environmental review process under Section 4(f) of the U.S. Department of Transportation Act of 1966, ODOT has requested the City's concurrence with a de minimis impact finding for Wallace Marine Park and Riverfront Park. The Interim City Manager will sign the necessary concurrence letters confirming that the planned construction activities will not result in adverse impacts to the parks' protected recreational features.
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ISSUE:
Information only.
RECOMMENDATION:
recommendation
Information only.
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FACTS AND FINDINGS:
No action is required by City Council. This item is for informational purposes to notify Council that the Interim City Manager, as the official with jurisdiction over the affected parklands, will concur with ODOT’s de minimis impact findings for Riverfront Park and Wallace Marine Park. This concurrence is required to satisfy requirements under Section 4(f) of the U.S. Department of Transportation Act of 1966 and allow the project to proceed with streamlined federal approval.
Coordination and Evolution of Park Impact Scope
The scope of impacts to Riverfront Park and Wallace Marine Park has been substantially reduced and refined over the past 18 months through ongoing collaboration between City staff and ODOT. Earlier in the project planning phase, the proposed construction footprint would have resulted in the removal of significantly more trees in both parks and included temporary occupancy of nearly the entire northern Riverfront Park parking lot.
To protect public park resources and minimize disruption, City staff initiated a peer review of the project design by an independent bridge engineer, which provided additional feedback on construction access and staging alternatives. That review, combined with ongoing technical coordination and negotiation with ODOT’s project team, led to several key refinements:
• Tree preservation: The number of trees identified for removal has been reduced significantly at both parks, and tree protection zones will be enforced during construction.
• Parking impacts: The footprint of the work zone in Riverfront Park’s northern parking lot was scaled back, preserving a large portion of public parking and reducing the amount of parking subject to long-term closures.
• Access commitments: Staff secured ODOT’s commitment to maintain continuous pedestrian, bicycle, and vehicular access to Riverfront Park and the park trail to the Union Street Railroad Bridge throughout the construction period.
• User impact mitigation: City staff negotiated accommodations for park users, including provision of temporary offsite parking during construction and event-specific measures for four major annual community events. These measures include suspension of loud construction activity during event days, shuttle service, and park ambassadors to support attendees and event organizers.
These negotiated adjustments reflect a coordinated effort by ODOT and the City to uphold the City’s long-term park stewardship responsibilities while allowing for the critical infrastructure upgrades needed to improve regional seismic resilience. Regardless of a de minimis determination, staff believe that the proposed mitigation measures are the best available without impeding ODOT’s ability to complete the project. The additional time and study required without a de minimis finding would likely only delay project implementation without appreciably changing the mitigation for construction impacts.
De Minimis Determination
Phase 1 of the Center Street Bridge Seismic Retrofit Project involves major retrofits to the river spans and east-side ramps. To complete the work, ODOT must temporarily use areas within Riverfront Park and Wallace Marine Park for staging, crane access, and material delivery. Under Section 4(f), ODOT has determined that project impacts to the parks meet the threshold for a de minimis finding-meaning the impacts are minor and will not adversely affect the parks’ recreational use or character.
The determination is based on three required elements:
1. No adverse effect on protected features or functions;
2. Public review opportunity (satisfied through outreach between February and April 2025); and
3. Written concurrence from the City as the jurisdictional authority over the parks.
BACKGROUND:
None.
Allen Dannen, PE
City Engineer
Attachments:
1. None.