News from King County Department of Transportation
Release date:  Feb. 14, 2006

King County announces preferred replacement option for South Park Bridge

The King County Department of Transportation announced today that the state Department of Transportation and Federal Highway Administration (FHWA) have approved a replacement alternative for the South Park Bridge spanning the Duwamish River. Following completion of a draft Environmental Impact Statement (EIS) and extensive public involvement last fall, the division recommended that the current bridge be replaced with a new drawbridge.

The condition of the 75-year-old span between Seattle and Tukwila on 14th/16th Avenue South has severely deteriorated in recent years, and was made worse during the 2001 Nisqually Earthquake. The FHWA rates the bridge a six out of a possible 100 points, one of the lowest ratings of any bridge in the State of Washington.

The county considered five alternatives during its environmental review, including rehabilitating the existing structure, constructing a fixed-span or movable-span bridge and removing the bridge entirely. Based on the outcome of the review and input by several agencies, residents and a citizen advisory group, a movable-span bascule bridge was determined to be the best replacement option. This alternative also presents the fewest community impacts.

“Following intensive review, King County believes a movable replacement bridge is the best option for both the south King County transportation network and the South Park community,” Department of Transportation Director Harold Taniguchi said. “But the future of this project is far from certain. The county continues to work with federal, state and regional transportation partners in an effort to put together a funding package for the bridge. While the project has been identified as a potential candidate for funding by the Regional Transportation Investment District, the bridge has yet to be formally added to the list of proposed projects.”

The cost of constructing a new bascule drawbridge is currently estimated at $90 million. If funding cannot be secured, the rapidly deteriorating bridge will need to be dismantled and removed by the end of the decade due to safety concerns. In addition to severing the community’s main transportation route, removal of the bridge will force more than 20 thousand vehicles a day on to nearby commuter and freight routes such as the 1st Avenue South Bridge, West Seattle Bridge, State Route 99 and Interstate 5.

The bridge also provides access to the residential communities of White Center, West Seattle, Georgetown and Boulevard Park. The bridge serves one of the largest industrial and shipyard complexes in the state and is used to haul freight to King County International Airport, Port of Seattle facilities, the Duwamish waterfront, rail facilities and the industrial areas of Kent and Auburn.

Now that the county has received state and federal approval of the replacement, the county will develop a final EIS and begin preliminary design. If funding can be obtained, the new bridge will be under construction as early as 2009.