The Washington State Department of Transportation (WSDOT) will mark a major milestone AT 3 p.m. today by signing a contract with Seattle Tunnel Partners to design and build the SR 99 bored tunnel.

In addition to Seattle Tunnel Partners’ proposal price of just under $1.09 billion, the contract includes funds allocated for inflation during the project and for bonding and insurance requirements.

In December, WSDOT opened bids and identified the best apparent value for design and construction of the bored tunnel to replace the SR 99 Alaskan Way Viaduct. Based on a combination of bid price and technical score, Seattle Tunnel Partners was named the apparent best-value bidder.

Signing ceremony takes place at 3 p.m. at the Port of Seattle Atrium. 2711 Alaskan Way.

For more information on the Alaskan Way Viaduct and Seawall Replacement program, visit www.alaskanwayviaduct.org.