Why is it needed? Project Phases The New Bridge The Detour Bridge Sustainability Diversity Program Field Work and Construction Updates Contractor Information
Past Events and Activities Past Committee Meetings School-Based Outreach Program
Library Newsroom Photo Gallery EIS Documents Links Frequently Asked Questions
Overview Before the Bridge Bridge Fever! The Great Bridge Scandal Gustav Lindenthal Construction and Dedication Need for Replacement River View Cemetery

Frequently Asked Questions

This page contains answers to questions we often hear about the Sellwood Bridge Project. If you have a question that you don't see addressed here, ask us and we'll get back to you. We may even update this page with your question.

Construction of the New Sellwood Bridge

Is the bridge still open?

Yes, the Shoofly (or detour bridge) is now carrying motorists, bicyclists and pedestrians across the river until the new Sellwood Bridge opens in the fall of 2015. Learn more about the detour bridge.

When will the bridge be finished?

The new bridge is expected to open in 2015 and the entire project should be completed in early 2016.

Why is there work during rush hour?

Construction crews are working to finish the new bridge as quickly and inexpensively as possible. If work was stopped during rush hour, it could cost millions of dollars more and could add months to the project schedule. Construction hours are usually from 7 am to 4 pm, so morning traffic is typically impacted more than afternoon traffic. There are limits to what the contractor can do during both morning and afternoon rush hours and the contractor’s traffic manager is constantly making adjustments in order to improve traffic flow.

When will drivers be able to turn south directly from the bridge to southbound Highway 43?

Drivers will be able to turn south from the bridge directly when the new bridge and interchange open to traffic in the fall of 2015.

What will the new bridge look like?

The new Sellwood Bridge will be a steel deck arch structure, with three arches supporting the deck of the main river spans. Learn more about the new bridge.

How long will the new bridge be?

The total length of the bridge, including three river spans and approaches on each side of the river, will be 1,977 feet.

How will I cross the river during construction?

The Sellwood Bridge, via the Shoofly detour, will remain open to motor vehicle and bicycle/pedestrian use except for occasional, short-term closures which will be announced well in advance.

What is the vehicle weight limit on the detour bridge?

The weight limit for vehicles using the Sellwood Bridge remains 10 tons (20,000 pounds).  This weight limit will remain in effect until the new bridge opens in 2015.

When will the bridge be closed during construction?

The project's goal is to have no more than 30 days (total) of bridge closures during the entire period of construction. During the project OR 43 (SW Macadam Avenue) will remain open, except for brief closures.

When was the detour bridge moved into place?

The original truss span was moved on January 19, 2013. The bridge was closed to all forms of traffic from January 17 to January 23 (one day quicker than anticipated). Learn more about the bridge move.

What will happen to the construction staging areas on the east and west sides of the river after the bridge is built?

Vegetated bioswales to treat stormwater runoff will be installed on the former Staff Jennings property (west side) and on the Mela property (east side). The County will work with the public and local agencies to identify future use for any remaining parcels. Parking for Powers Marine Park will be moved west across Highway 43 (west side). The Willamette Shoreline trolley track will be restored after construction is completed (west side).

How do I get regular updates about construction?

You can sign up for our interested parties list to receive infrequent information about major closures and project milestones, and/or you can sign up for weekly field work updates that provide more detailed information about what is going on at the project site.

What will happen to the old bridge?

The concrete bridge approaches and river piers will be demolished and their material recycled. After the detour bridge is removed in 2015, the green steel truss spans of the old bridge will likely be recycled into new steel. As a historic structure, the old truss spans could be moved and reused as a bridge. The new owner would need to pay to move the spans and remove old lead paint.

Who designed the new bridge?

T.Y. Lin International designed the new bridge.  The global engineering firm is also the engineer-of-record for TriMet’s Portland to Milwaukie light rail bridge across the Willamette.  CH2M HILL designed the roadway elements of the Sellwood project.

Who will construct the new bridge?

Slayden-Sundt Joint Venture is the general contractor responsible for constructing the new bridge.  The venture is a joint effort of Slayden Construction Group, from Stayton, OR, and Sundt Construction, from Tempe, AZ.  Slayden is also the contractor for the Willamette River I-5 bridge in Eugene, OR.  The joint venture hires subcontractors who perform specialty tasks for the project, ranging from excavation to electrical work.


What is the funding plan for a new bridge?

The current cost estimate for the Sellwood Bridge Replacement is $307.5 million (in 2014 dollars, the projected middle year for construction). This is $38.5 million more than the $269 million estimate at the 60% design phase and $22.5 million less than the $330 million estimate at the end of the planning phase. The cost includes the new bridge, an interchange where the bridge connects with Highway 43, right-of-way, design, and mitigating impacts to protected resources. The funding plan includes the following sources:

  • $141.7 million - Multnomah County VRF ($19 per year vehicle registration fee)
  • $22.7 million – Multnomah County VRF (collected)
  • $74.7 million - City of Portland (new revenues from the Oregon Jobs and Transportation Act)
  • $35 million - State of Oregon (Jobs and Transportation Act) for Highway 43 interchange
  • $17.7 million - Federal TIGER grant
  • $15.7 million - Previously secured federal funds

Why has the project cost increased?

It is normal for cost estimates to change on large construction projects as the design progresses, and costs are confirmed. Early cost estimates can increase as a contractor gets actual bids and more information is learned about the construction site. Some reasons for the increased cost include:

  • Unstable rock along the Highway 43 hillside will require retaining walls instead of an open face rock cut;
  • Higher costs to stabilize the landslide at the bridge’s west end;
  • Higher market prices for steel, fuel and other materials; and
  • More contaminated soil under Highway 43 and the railroad that is more expensive to remove and dispose of
  • More complex design due to site conditions and other constraints
  • Real bid pricing (not estimates) based on more detailed design

The cost increase can be covered without raising the county’s vehicle registration fee because bond interest rates are near historic lows. Low rates allow the county to bond more money using the same revenue. 

What about the Multnomah County vehicle registration fee? How much is it?

In 2009, Multnomah County's Board of Commissioners adopted a $19 per year county vehicle registration fee to help fund a new Sellwood Bridge. As required by state law, revenue from this fee can only be used to replace the Sellwood Bridge.

Existing Sellwood Bridge

How safe was the original bridge?

The problems with the Sellwood Bridge were well known: foundation problems, general deterioration, and a narrow, lightweight design that poorly serves all traffic modes. Multnomah County maintained a rigorous safety program that included visual inspections every three months to ensure that the bridge continued to be safe to use. The weight limits imposed in 2004 helped preserve the structure. In 2008 the County injected glue in cracked sections of concrete to seal them against corrosive water and air. The County also monitored slope movement on the west side that could endanger the bridge. If Multnomah County ever determined the bridge was not safe to use, the bridge would have be closed.

How safe is the detour bridge?

The temporary detour structure is as strong as, if not stronger, than the original Sellwood Bridge (including seismically). The weakest part of the old bridge (the west approach) is not part of the detour bridge.

What are the Sellwood Bridge's main deficiencies?

The bridge has numerous deficiencies, including:

  • Poor structural condition, with a limited service life
  • Vehicle weight restrictions, which have forced an average of 1,400 trucks and buses each day to find a different river crossing route
  • Geologic instability on the west end that has damaged the bridge (not applicable to the new detour bridge)
  • Narrow travel lanes with no shoulders or median
  • Short stopping distances and lines of sight for motorists
  • One narrow sidewalk insufficient for bicyclists and pedestrians
  • Poor connections to established trails at each end of the bridge
  • Tight ramps at west end that cannot easily accommodate large vehicles
  • High risk of structural failure in an earthquake
  • A National Bridge Inventory sufficiency rating of 2 out of a possible score of 100 (see next question)

What makes this particular river crossing so important?

The Sellwood Bridge is very important to the Portland metro region because of its location. The bridge provides the only crossing for a 12-mile stretch of the Willamette River between Oregon City and Portland, and it connects several state highways, including Oregon 99E, 43, and 224. It is the busiest two-lane bridge in Oregon, with an average daily traffic count of 30,000 vehicles. It is also located in a heavily populated area that is experiencing high density development. 

Who uses the Sellwood Bridge?

Due to the lack of other river crossings in the southern metro region, and its close proximity to the Multnomah/Clackamas County line, the Sellwood Bridge serves a diverse group of users. The bridge is a primary east-west connection for residents and businesses in west Portland/Washington County and those in Sellwood, Milwaukie, and Clackamas counties. Many bridge users are commuters who live in Clackamas County. In fact, eighty-three percent of Sellwood Bridge trips begin or end outside the Portland city limits. Prior to the reduction of weight limits in 2004, the bridge was an important secondary freight route, especially for local deliveries. Weight limits prevent many delivery trucks from using the bridge, forcing out-of-direction travel that adds to congestion on other routes and increases costs to businesses and consumers.