North Shore Road Bridge Retaining Wall Improvements

During a July 2021 inspection, the City discovered cracks and movement in the retaining wall on the east side of the northern approach to the North Shore Road Bridge, which supports the approaching roadway. To maintain public safety, since July, the bridge has remained closed to all vehicular traffic.

Since that time, the City has been developing a scope of work under a Construction Manager/General Contractor project delivery approach. We have recently contracted with DOWL for design services and Emery and Sons for construction services.

Next Steps

This fall, the design team will begin performing detailed testing and analysis of the retaining wall and surrounding area to determine the extent of the defects. Once this is complete, the project team and City will explore alternatives and select a preferred alternative. Depending on the preferred option, construction is anticipated to begin in early 2022 and be complete in spring 2022.

To maintain safety, the bridge and roadway are expected to remain closed to vehicular traffic until the structural analysis and any recommended repairs are completed. At this preliminary stage, we are hoping to reopen the bridge in spring 2022, however this is subject to change.

FAQs

[Updated 10.12.21] 

Why is the North Shore Road Bridge closed?

During a July 2021 inspection, the City discovered cracks and movement in the nearby retaining wall, which supports the approaching roadway. To maintain public safety, the North Shore Road Bridge is closed to all vehicular traffic as the City conducts structural analysis of the retaining wall and approaching roadway. There are concerns with the retaining wall and roadway, not the bridge itself.

What did you base your decision for closure on?

The decision to close the retaining wall (and adjacent bridge) was based on visual assessments from geotechnical and structural engineers, and our own field investigations that indicated cracking and movement between the wall and the roadway.

The survey data shows that the NE corner approach of the retaining wall appears to have moved about an inch in the past two years, and is bowing outward. 

What about the condition of the bridge?

The bridge itself does not appear to be of concern based on the latest bridge inspections performed by ODOT.

How long will the bridge and road be closed for?

To maintain safety, the bridge and roadway are expected to remain closed until spring 2022. This allows for structural investigations and repairs to be completed.

What is the timeline for the structural analysis and potential repair work?

In late September, the City contracted with a design firm and a construction team to perform detailed testing and analysis of the retaining wall and surrounding area to determine the extent of the issue and develop recommendations. Below is an outline of the estimated schedule and scope of work:

  • Site visits, testing, vegetation removal, and investigations: October – November 2021
  • Report and geotechnical recommendations: November – December 2021
  • Final design and procurement: Late 2021
  • Potential repairs or construction: Early 2022
  • Bridge and roadway reopen: Spring 2022

Any repairs will be in coordination with the Department of State Lands, Lake Corporation, and any private utilities in the area. Please note, schedules are preliminary and subject to change.

What are the work hours for the structural analysis and possible repairs?

Approved work hours are 7 a.m. – 6 p.m. Monday to Friday.

Is the bridge and roadway open to people walking, rolling and biking?

Yes, a safe temporary access route has been established over the bridge for people walking, rolling, and biking. Please watch for signage and follow the channelization devices.

Why is the bridge open for people walking, rolling and biking if it is not safe for vehicles?

The North Shore Road Bridge is closed to vehicles due to the high volume of traffic and traffic weight that uses the bridge and approaching roadway. The bridge is a high traffic route during commute hours, as well as frequently used by delivery and construction trucks. This creates unnecessary stress and weight to the roadway and retaining wall.

The Bridge and roadway is open for people walking, rolling and biking since these activities do not add significant weight to the structure. After further expert analysis and continuous monitoring, future long-term closures might be needed.

I live in the local area, can’t I travel over the bridge and through the road closure signs?

No, the road closed signs are there for a reason – to keep you safe and vehicles out of the closure area. Please do not attempt to move the barricades or travel past the signs, even if you live in the local area. 

Are boats still allowed to access under the bridge, if so, why?

At this time, Lakecorp is still allowing boating access under the bridge. The structural concerns appear to be with the retaining wall and approaching roadway, not the bridge itself. However, this is subject to change. The City is coordinating closely with Lake Corp and any changes will be posted here.  

How often is the bridge inspected?

As a part of managing our roadways and bridges, the City has routine analysis done on our transportation system. ODOT inspects our bridges typically every other year. The North Shore Road Bridge specifically has been routinely monitored and surveyed since 2014.

Will my trash or mail service be interrupted?

The City has notified Republic Services and USPS about the closure. If you have additional work at your home (landscaping, construction, etc.), please let them know to use an alternate route.

What about emergency vehicle access?

The bridge closure will not impact emergency vehicle access. There will be no interruption to emergency response – Police and Fire will be able to access the area from the north or the south.

Project Updates: 

Project Update October 12, 2021

Starting the week of October 18, a test pit will be excavated within the closed area, so crews can conduct more thorough geotechnical investigations. In addition, crews will begin removing extensive invasive vegetation on the retaining wall on the west side of the northern approach. (Please see attached image showing the approximate limits of the vegetation removal).

What to expect over the coming months (prior to major construction):

  • Surveyors and crews may be visiting the site intermittently to conduct investigations.
  • Work hours are 7 a.m. – 6 p.m.
  • Pedestrian access is expected to remain open during most times. There may be short periods where traffic is held to accommodate crews and equipment.
  • A small floating dock/barge will be located next to the wall. At times, excavators and dump trucks will access the site and the test pit location. Please expect an increase in noise and truck traffic.
Project Details
ID: 
WO 324
Year: 
2021
Status: 
Active
Project Contact: 

David Kudna

Project Manager

503-635-0261

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