The central waterfront is home to many critical utilities, not only to serve the piers but to reach a broad local and regional network. Large stormwater and combined sewer overflow systems, high voltage electrical systems, steam and high capacity natural gas lines, water and sewer mains, as well as several telecommunications networks all create a complex network of utilities under the street and below the piers. 

Nearly 75 years of additions and changes have resulted in crisscrossed utility services, and the passage of time means that some of these utilities were not always well documented. 

 

Many of the existing utilities were unavoidably in the path of construction and needed to be temporarily relocated to keep the lights on the water running. At several locations along the construction zone, the project built temporary utility bridges to allow utility connections to span the large excavation pit. 

 

Once the temporary utility lines cross the work zone, they run under the piers to provide service during construction.

 

When construction is complete, temporary utilities will be transferred to permanent services. New utility services will be installed under the new roadway and connect to the piers through pre-formed holes in the seawall's face. 

 

New utility lines are placed into wood forms, which are then covered in concrete and buried under the roadway.

  

The new seawall was also designed to better manage stormwater on the new Alaskan Way surface street. Near University Street, a huge, 48-inch stormwater outfall has been installed.

Click here for 6: Jet grout installation.

For more information about the Seawall Project, visit our website.