Information for residents and businesses in Pioneer Square

Recently, our team detected approximately one inch of ground settlement near the pit Seattle Tunnel Partners is building to access and repair the SR 99 tunneling machine. Settlement was also detected on the Alaskan Way Viaduct and some of the buildings that we are monitoring; the amount of settlement lessens in the surrounding area. Our experts are still analyzing data and conducting daily inspections of the viaduct, but the initial settlement we reported publically on Dec. 5 has since stabilized. 
 
We have identified approximately 30 buildings that warrant further investigation. We are working with property owners and managers to complete interior visual inspections of these buildings. These inspections are being completed by a historic architect and include a survey of the building to look for impacts to significant architectural elements or other indications of damage.
 

Frequently Asked Questions

 

We’ve received a number of questions from residents and businesses in Pioneer Square regarding recently measured ground settlement in the neighborhood. Below are answers to some of the most common questions. We’ll continue to update this list as we gather additional information. 

If you live, work or own property in Pioneer Square and have questions or concerns, please call 1-888-AWV-LINE or email viaduct@wsdot.wa.gov.

What kind of settlement has WSDOT seen near the access pit and in Pioneer Square?

We installed a state-of-the-art settlement monitoring system as part of the SR 99 Tunnel Project. Recently, Seattle Tunnel Partners surveyors detected over an inch of ground settlement near the pit crews are building to access and repair the SR 99 tunneling machine. We have also seen similar settlement on the Alaskan Way Viaduct; the amount of settlement lessens in the surrounding area.

Have buildings been damaged in Pioneer Square? 

We have identified approximately 30 buildings that warrant further investigation. We are working with property owners and managers to complete interior visual inspections of these buildings. These inspections are being completed by a historic architect and include a survey of the building to look for impacts to significant architectural elements or other indications of damage. A number of these surveys have already been completed and the project team continues to schedule surveys as needed. So far, our team has seen a small amount of cosmetic cracking in masonry and drywall but no indications of structural damage.

How would settlement affect my building?

You may notice new cracks or changes to existing cracks in your building. You may also notice doors or windows that are sticking or do not open properly.  If the building settles more than the ground outside, utility services also could be disrupted. If you notice such changes in your building, please keep a list or take photos, and follow the contact information below. 

What should I do if I see new damage in my building?

If you are a resident or tenant, please contact your property manager or building owner. Building owners should contact the Alaskan Way Viaduct Replacement Program (1-888-AWV-LINE or viaduct@wsdot.wa.gov) to report any settlement-related concerns. If you have photos, please share them with our staff. 

How do I file a claim if I have building damage?

If you feel your building has been damaged as a result of ground settlement, you can file a claim with WSDOT. Please contact 1-888-AWV-LINE or viaduct@wsdot.wa.gov for instructions on filing a claim and to speak with project staff. 

What is WSDOT doing to protect buildings that may be affected by settlement? 

We implemented a comprehensive program to monitor ground movement during SR 99 tunnel construction. Crews are currently analyzing data from this system and conducting extensive surveys near the work zone. If damage occurs to buildings or infrastructure as a result of tunnel construction, we will be responsible for costs associated with repairs. 

Based on a thorough analysis of data, it appears that additional settlement is not occurring, though we will continue to closely monitor the situation. 

Can WSDOT expand the monitoring program to include more buildings?

Our monitoring system was designed to measure ground movement during tunneling. As part of that system, monitors were installed both in the ground and on structures. The most significant settlement has occurred in areas that include both ground and building monitors. However, some recent settlement has occurred in areas that are not actively monitored. As a result, we do not have specific settlement data for some of these buildings.   

Structural engineers and surveyors are inspecting buildings and infrastructure in all areas where settlement was detected. Decisions about the scope of the monitoring program will be made after that analysis is completed.

Does WSDOT have a plan if settlement continues?

Protecting people and infrastructure is our top priority. Protocols are in place to address a range of potential issues that could arise as a result of ground settlement. WSDOT and STP are prepared to shut off the dewatering system if it becomes necessary.