District 1 City Councilmember Lisa Herbold shared this via her constituent email on Friday Aug. 13

The West Seattle Bridge Community Task Force met on August 12.

Bridge Updates

First of all, SDOT confirmed the project remains on schedule for completion in mid-2022, and provided an update about how future schedule and cost estimates will be determined.

As I’ve explained in past blog posts, SDOT is using the General Contractor/Construction Manager (GCCM), which varies from standard contacting methods. Normally, a project is designed, and then put out to bid. The GCCM approach saves time by involving the construction contractor in design at 60% and 90% design, to identify potential challenges, and avoid change orders that can delay projects.

SDOT has provided the construction contractor, Kraemer, with a 60% completed design.  This will enable them to develop a first estimated cost/schedule estimate later this month. After 90% design is reached next month, a second estimate will be due in October. At that point, the Maximum Allowable Construction Cost (MACC) negotiations will begin, and construction will begin in November. The schedule below notes this, along with funding agreements with other funders, such as the federal government, in September:

Some work has been taking place on the bridge, such as asbestos work. Being inside the box girder, the work isn’t visible from outside.

What Went Wrong?

Graphics below are in response to public questions about what went wrong with the bridge. The original bridge was designed to the standards of that time, which did not include adequate post-tensioning of steel cables. This led to the cracking of concrete.

There are three spans to the bridge: the center span, and the two approaches. Cracking took place in all three spans. The center span across the Duwamish has been stabilized, which sharply limited crack growth. The two tail spans have not yet been stabilized; the repair will add post tensioning to the two tail spans:

Another question from community members is why a lane of traffic can’t be opened in the meantime.

SDOT indicates traffic would cause more cracking and harm the condition of the bridge, with the tail spans needing additional work to strengthen. The repair will add post tensioning to the entire bridge. In addition, there are holes in the deck used to access the box girders.

Reconnect West Seattle Update

Through August 1, over 1,500 applications for use of the lower bridge have been received, with the following access granted:

Traffic travel times on detour routes such as West Marginal Way are up significantly from last year; bus ridership and water taxi ridership are increasing slowly:

The West Marginal Way/Highland Park Way intersection improvements, designed to improve intersection throughput and concurrent turning movements, are on track to be completed by the end of September.

South Park Drainage and Roadway Partnership Project Update

SDOT also presented the South Park Drainage and Roadway Partnership Project.  This is a joint project between SDOT and Seattle Public Utilities to construct street improvements and drainage systems to address flooding that regularly occurs in some parts of South Park. The project includes a new pump station. I last wrote about the pump station here when construction began last Fall.

The project will take place in the South Park Industrial Area between 2nd Ave S and 8th Ave S, and S Holden St and S Monroe St.

For the map below, the blue lines are where street AND drainage improvements will take place, and the one yellow block is where only drainage improvements are planned:

The project will begin in September, and take 12-16 months. Project elements are noted below:

Work will begin first on South Monroe and South Chicago Streets, which are currently gravel roads.

Construction details are below: