Reinforcement of the George Washington Memorial Bridge (also known as the Aurora Bridge) has begun. For those who live, and work, beneath the structure, this hardly comes as news.
Begun on Wednesday, June 1st, the 18-month project has already shut down portions of Troll Avenue, the street directly beneath the Fremont portion of the bridge structure. The $5.7 million project, funded by gas tax monies, is the third, and final, phase in a plan to strengthen the structure to better withstand a major earthquake, according to a press release issued by the Washington Department of Transportation (WSDOT.)
Actual work has been contracted with Massana Construction, the same company that successfully completed installation of a safety fence along the deck structure of the bridge earlier this year.
A significant piece of the seismic reinforcement involves wrapping 14 columns that support the bridge in concrete covers and specialized ‘jackets’ designed to prevent the columns from failing in a major earthquake. Mindful of the status of the bridge as a national historic structure, and a city landmark, WSDOT engineers worked with seismic specialists using a special fiber reinforced polymer for wrapping the north end columns, along Troll Avenue – often called ‘The Hall of Giants.’ These columns, as designed by engineer Ralph Ober, were created in a unique cruciform shape, and maintaining that shape after the wrapping has taken extra consideration.
Most construction will take place beneath the bridge deck, which means that bridge closures will be limited to a handful of nights, according to the WSDOT press release. Two-lane closures will take place at night, with single-lane closures during the day. Streets under the bridge will also be periodically closed, as the construction crew requires access to the structure. Street parking will be removed for periods of time.
This project will require some noisy work, including removing of old rivets – a noise neighbors will recall from work on the safety fence. Most of this noise will be limited to daytime hours. However, WSDOT representatives predict three nights during project will require the crew use jackhammer. WSDOT has promised advance notice to local residents of these dates.
Construction should be complete by fall of 2012. More information can be obtained through the WSDOT website.