View entire map This TPA project will replace the old, narrow bridge over Chiwaukum Creek, just above Tumwater Canyon (MP 89.88-89.91), ten miles west of Leavenworth in Chelan County.
View entire photo The new bridge will carry more weight and be much wider.

View entire photo A closer view, looking north at the south side of the bridge.
Project Facts
- The current bridge was built in 1936, has a span of 202 feet, and has two 12-foot lanes with no shoulders.
- The current project proposal includes a new structure that will have two 12-foot lanes and two 8-foot shoulders.
- This project will may take two construction seasons to complete and may involve changes in the highway alignment to accommodate construction staging.
Fall 2008
The project is currently in the design phase, with a scheduled construction start in late spring 2011. Depending on the final design option chosen, this project may take two seasons to complete.
Survey data, geotechnical information, and environmental resource data continues to be gathered to design different alternatives to minimize identified environmental impacts.
This Catastrophic Reduction Structure Preservation project replaces an old bridge on US 2 just above Tumwater Canyon, ten miles west of Leavenworth in Chelan County.
Why is WSDOT
replacing the Chiwaukum Creek Bridge?
The current steel girder structure is functionally and structurally obsolete, which means it doesn't meet today's design standards for traffic loads (weight) and roadway width. Originally built in 1936, the bridge has undergone various retrofits to improve the deteriorated concrete bridge rails and also to try to reduce undermining of the footings from Chiwaukum Creek due to scour. (Washing out the soil under the footings). The age and design of the bridge requires regular maintenance and doesn't allow for widening so replacement is the only option.
The End Result
The current proposal for a new structure includes two 12-foot lanes with 8-foot shoulders. A great improvement over the current bridge which has two 12-foot lanes and no shoulders. The new structure will also be reconfigured to span Chiwaukum Creek with less impacts to the stream, reducing the need to clear debris (logs jams, etc.) from the bridge footings after high flow events and eliminating the undermining of the foundations due to creek scour.
Project Benefits
Traffic Safety - Provides a wider bridge with shoulders to pull onto.
Truck Safety - Oversize loads will also be better accommodated with a wider bridge deck.
Pedestrian and Bike Safety - Two 8-foot shoulders provide bicycles and pedestrians a much safer crossing.
Environmental - Reconfiguring the creek crossing and the new bridge's design will reduce backwatering and debris accumulation. Replacing the old steel girder bridge with a concrete girder structure, eliminates the need to paint it on a regular basis. Fish enhancements to the creek bed are also included in the design.
What is the project timeline?
The project is currently in the initial design phase, with a scheduled construction start in late Spring 2011. Depending on the final design option chose, this project may take two seasons to complete.
This project is planned to be constructed in conjunction with the US 2 - Wenatchee River Bridge Replacement, which is located 3/4 of a mile to the east at the head of Tumwater Canyon.
Public Involvement
In August of 2006, an Interdisciplinary Scoping Team (IDT) workshop was held with project stakeholders to identify the environmental constraints on the project and propose solutions to minimize those impacts.
Your thoughts and opinions are important to us. If you have questions or comments about this project, please let us know by using the contact information below.
Environmental Protection
WSDOT is committed to protecting the environment and is making every effort to assess and minimize any negative impacts from this project. All applicable environmental laws and guidelines are being followed.
Please visit the WSDOT Environmental
Services Web site for more information.
Increasing safety is one of our priorities
As one of the primary highway accesses to North Central Washington from the Puget Sound area, improving safety for those coming to this tourist dependent region is critical. At the same time, safety during construction is critical and a work zone and traffic safety plan is being developed to protect motorists and the construction workers while the work is underway.
Will this project impact tribal resources?
Coordination with the Tribes is ongoing and will continue to be a critical aspect of this project.
WSDOT seeks to address the concerns of the tribal nations using the process outlined in Section 106 of The National Historic Preservation Act and the WSDOT Tribal Consultation Policy adopted in 2003 by the Transportation Commission as part of the WSDOT Centennial Accord Plan.
Financial Information
This project is funded through the following source:
How can I get more information?
Contact:
Bob Romine, Project Engineer
WSDOT North Central Region
P.O. Box 98
Wenatchee, WA 98807
Phone: (509) 667-2880 or toll free (888) 461-8816
Email: rominer@wsdot.wa.gov
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