LOCATION
Portland, Oregon

CLIENT
Oregon Dept. of Transportation
Multnomah County Transportation

PARTICIPANTS
Abhe & Svoboda, Inc.
David Evans & Associates

SCOPE OF WORK
Abrasive Blasting
Painting
Lead Abatement & Containments
Scaffolding & Rigging
Structural Steel Repair
Bridge Deck Replacement
Electrical Systems Renovation

VALUE
$17.43 million

SCHEDULE
March 1998 - April 1999

ADDITIONAL INFORMATION
Multnomah County
Hawthorne Bridge Project Website

Portland, Oregon is home to several historical and unique bridges. Built in 1910, the Hawthorne Bridge is the oldest bridge in Portland and it is also the oldest vertical-lift bridge in the United States. Two 165ft tall towers on either side of the lift span house 450-ton counterweights, which are used to raise/lower the lift span. The tall towers also make the Hawthorne Bridge a recognizable feature of Portland’s landscape.

In 1998, Abhe & Svoboda, Inc. was awarded a contract to undertake a major renovation of the bridge, which included coatings work, sidewalk widening, concrete pier widening and post-tensioning, and structural repairs and upgrades, and mechanical rehabilitation of the lift span.

The bridge is a six span overhead truss bridge. The fifth span is a vertical lift span, capable of a vertical movement of 110 feet, which provides a lateral waterway clearance of 230 feet. Two 165foot tall towers on each side of the span house the counter weights used to lift the span.

Abhe & Svoboda, Inc. removed all of the lead-based paint from the above and below deck steel structure as well as the concrete counterweights. Abrasive blasting with recyclable steel grit was used to clean the steel surfaces. SSPC Class 1A containment systems were used during lead abatement and painting procedures, including a specially-designed movable containment system. A Waser High Tech Coatings moisture-cure polyurethane paint system was applied to all steel surfaces.

Abhe & Svoboda, Inc. also performed significant structural repairs and upgrades. The existing bridge deck was removed from all six spans and replaced with a new galvanized steel grate bridge deck. Steel braces supporting the counterweight towers and the counterweight lift cables were replaced.

The sidewalks were widened 10ft allowing more pedestrians and bicycle commuters to use the bridge. The steel channels and floor beams that were added during these operations allow the Hawthorne to accommodate light rail commuters in the future.

The Hawthorne Bridge painting project was finished ahead of schedule.