State Route 4 Old River Bridge Maintenance

Project Description

This project proposes to perform mechanical and electrical repairs on the Old River Bridge #29-0045 over Old River east of Discovery Bay at the San Joaquin and Contra Costa County Line. 


Project Benefits


The purpose of this project is to provide preventive maintenance in order to delay or minimize the bridge's future rehabilitation needs and to make the moveable bridge in good operating condition comply with Title 33, Code of Federal Regulations (CFR) 117.183.


There is a need to upgrade the existing mechanical and electrical components and implement structural repairs to this 100-year-old bridge to increase the reliability and serviceability of this swing span bridge.


Construction Impacts

Expect one 55-hour weekend closure of State Route 4 during construction in the month of October 2022. The project is expected to complete construction in Spring of 2023.  


Funding Source

The project is programmed in the 2016 State Highway Operation and Protection Program (SHOPP) under the Bridge Preservation Program in fiscal year 2019/20.


Project Cost/Programmed

Programed Project Cost Capital $ Support $
Project Approval & Environmental Document $0 $748,000
Plans, Specifications, & Estimates $0 $1,614,000
Right of Way $220,000 $65,000
Construction $7,909,000 $1,549,000


Projected Cost as of (June 23, 2022) Planned $ Expended $
Project Approval & Environmental Document $748,000 $661,000
Plans, Specifications, & Estimates $1,614,000 $1,517,0000
Right of Way $285,000 $63,000
Construction $9,458,000 $408,000


Current Schedule

Project Study Report (M010) Summer 2015 (A)
Project Approval & Environmental Document (M200) Summer 2018 (A)
Right of Way Certification (M410) Spring 2020 (A)
Ready to List (M460) Summer (2020)
Approved Construction Contract (M500) Spring 2021 (A)
Project Completion (M600) Spring 2023

*Milestone Achieved (A)


Project Status

Currently the project is in construction and expected to be completed in Spring of 2023.


Project Contact

Caltrans District 10 - Public Information Office
Phone: (209) 948-7977


Title VI Information

The California Department of Transportation (Caltrans) assures that no person shall, on the basis of race, color, or national origin, be excluded from participation in, be denied the benefits of, or be otherwise subjected to discrimination under any program or activity receiving Federal financial assistance, as required by Title VI of the Civil Rights Act of 1964, as amended, the Civil Rights Restoration Act of 1987, and Federal Executive Order 12898 (Federal Actions to Address Environmental Justice in Minority Populations and Low-Income Populations).

Caltrans will make every effort to ensure nondiscrimination in all of its programs and activities, whether they are federally funded or not, and that services and benefits are fairly distributed to all people, regardless of race, color, or national origin. In addition, Caltrans will facilitate meaningful participation in the transportation planning process in a nondiscriminatory manner.