Bridge Maintenance Projects

Bridge scour projects either remove excess soil from stream channels or replace soil around foundations that has been washed away during high water events.

Want to know more about bridge scour? Watch a video about how we keep our bridges safe.

Projects scheduled for 2018

The following projects are scheduled for 2018. The schedule may change due to weather and other conditions.

Amisigger Road Bridge over Deep Creek – In Progress

  • What: Install 42 pieces of large wood along the southern bank upstream of the bridge to protect the bridge supports from further erosion.
  • Why: A routine bridge inspection in 2009 revealed that a bridge support on the south side of Deep Creek had been eroded and a scour hole was created, which destabilized the base of the support. At that time, Clackamas County received an emergency authorization to provide immediate protection and stabilization of the affected support. We plan to further stabilize the bridge support and embankment and provide habitat enhancements to Deep Creek.
  • When: This project is expected to take 4 to 6 weeks to be complete by Aug. 31, 2018; work hours: 7 a.m. to 5 p.m., Monday through Saturday.
  • Traffic impact: No road closure is planned, but there will be traffic delays of up to 20 minutes at a time.

Baker’s Ferry Road over Foster Creek (near Foster Creek Lane)

  • What: Install large wood pieces and boulders upstream of the culvert to deflect water flow away from retaining walls and the culvert foundation. Install several rows of boulders spanning the width of Foster Creek to provide grade control, slow migration of streambed material and maintain fish-passage.
  • Why: In 2001 Clackamas County replaced the undersized culvert with an open-bottom “fish-friendly” culvert to allow the streambed to act naturally. As expected, streambed material migrated downstream as a result of the return of natural water flow. Foster Creek continues to transport streambed material downstream, which threatens to further erode the retaining walls and base of the new culvert. Adding wood and boulders will slow down and deflect flow away from the retaining walls and culvert foundation.
  • When: This project is expected to take 4 to 6 weeks to complete between July 15 and Aug. 31, 2018; work hours: 7 a.m. to 5 p.m., Monday through Saturday.
  • Traffic impact: No road closure is planned, but there will be traffic delays of up to 20 minutes at a time.

Buckner Creek Road/Newkirchner Road Bridge over Buckner Creek – Project Complete

  • What: Replace two decayed bridge pilings, and excavate, grade and add boulders along the banks of Buckner Creek upstream and downstream of the bridge.
  • Why: Through a routine inspection, we discovered two decayed pilings, a large amount of erosion on the northern bank upstream of the bridge and aggradation (increase in land elevation because of sediment) along the southern bank downstream of the bridge.
  • When: This project is complete.
  • Traffic impact: The road will be closed to all traffic. Please follow the detour route.

Kuehn Road Bridge over Kellogg Creek – In Progress

  • What: Replace two decayed bridge pilings, and excavate and add boulders along the southern bank of the creek upstream of the bridge. Boulders and native vegetation will primarily be used for the bank repair.
  • Why: Through a routine inspection, we discovered two decayed pilings and a potential for scour-related damage upstream of the bridge on the southern stream bank where a shifted concrete “blanket” is allowing erosion to occur.
  • When: This project is expected to take up to 3 weeks to complete; Aug. 1-24, 2018; work hours: 7 a.m. to 5 p.m., Monday through Saturday.
  • Traffic impact: No road closure is planned, but there will be traffic delays of up to 20 minutes at a time. The bridge will have a temporary 5-ton weight limit while the pilings are being replaced, which is expected to last up to 2 days.

Wilsonville Road Bridge over Corral Creek - In Progress

  • What: Excavate and add boulders along the north bank of the creek upstream of the bridge. Add boulders along the upstream concrete retaining wall. Regrade the creek bottom under the bridge.
  • Why: Through a routine inspection, we discovered some minor erosion on a portion of the bridge foundation and on an upstream concrete retaining wall, some areas of bank destabilization, and aggradation (increase in land elevation because of sediment) in the channel under the bridge.
  • When: This project is expected to take up to 2 weeks to complete; Aug. 14-28, 2018; work hours: 7 a.m. to 5 p.m., Monday through Saturday.
  • Traffic impact: No road closure is planned, but there will be traffic delays of up to 20 minutes at a time.

Still Creek Road Bridge over Still Creek

  • What: Remove excess concrete from the streambed.
  • Why: Excess concrete prevents inspection of the bridge footings and has narrowed the width of the stream channel
  • When: This project is expected to take two weeks to complete sometime between Aug. 6 and Aug. 24, 2018; work hours: 7 a.m. to 5 p.m., Monday through Saturday. If weather or other conditions delay other bridge scour projects planned for earlier this summer, this project may be postponed until 2019.
  • Traffic impact: No road closure is planned, but there will be traffic delays of up to 20 minutes at a time.
  • Additional work potential: After the excess concrete is removed, the bridge footings will be inspected for erosion. It is possible that additional work will be needed in 2019.

Projects completed in 2017

Monte Cristo Road BridgeMonte Cristo Road Bridge over Garrett Creek
Replaced decayed bridge piling, and excavated, graded and added support to the southern bank of the creek upstream of the bridge using boulders and native vegetation.

 

 

 

Wilhoit Road Bridge (near Bird Road) over Rock Creek
Excavated accumulated material on the upstream west bank of Rock Creek, installed boulders and native vegetation along a portion of the upstream east bank, and installed 2 "stream barbs" to minimize future erosion. (Stream barbs are structures that project out from a streambank to redirect water flow away from an eroding stream bank.

 

 

Casa Del Rey Pedestrian Bridge over Mt. Scott Creek
Installed boulders and native vegetation, and stabilized the support structure on the north end of the bridge. This bridge is owned by the City of Milwaukie and maintained by the North Clackamas Parks and Recreation District (NCPRD). NCPRD asked the County Department of Transportation and Development to manage this project on their behalf.