BRIDGE SEISMIC RETROFIT PROGRAM IN WASHINGTON STATE

Earthquakes pose a serious risk to life and infrastructure in Washington State, particularly the Puget Sound region. Recognizing the earthquake risk to State owned bridges, the Washington State Department of Transportation (WSDOT) developed a bridge seismic retrofit program to address bridges that do not meet current seismic response design standards. The program is divided into three phases: Phase 1 addresses simply supported bridges and bridges with in-span hinges; Phase 2 addresses Major bridges and bridges with single column supports; Phase 3 addresses bridges with multiple columns. Nearly $100 million has been spent to date to seismically retrofit bridges in high-risk zones that include: 191 bridges completely retrofitted; 15 bridges in progress; 716 bridges remaining.