Contra Costa County Requests Public Input on Vasco Corridor Safety Improvement Study Report

Martinez, CA – Contra Costa County Public Works (Public Works) has completed a corridor safety and improvements study on the portion of Vasco Road located between Marsh Creek Road / California State Route 4 and the southern Contra Costa County / Alameda County line to identify and address safety, traffic, roadway infrastructure, and environmental concerns.

The study delineates priority safety improvement projects and recommendations for future grant funding and implementation. During the study development, Public Works sought input from Vasco Road users and community members through an online survey featuring the Vasco Road Mapping Data Collection Tool and held three (3) community outreach workshops with District 3 Supervisor Diane Burgis to coincide with key milestones.

The outreach efforts resulted in the Vasco Road Corridor Safety Improvement Study Final Report. Public Works invites the public to review this report and provide feedback to [email protected] by Tuesday, September 15, 2026.

To learn more about the study, visit www.contracosta.ca.gov/Vasco-Road-Corridor-Safety-Improvements.

On a related note, the State Route 4 Bypass Authority and its consultant have completed the design for the Vasco Road Safety Improvements Phase 2 Project. The work to be done generally consists of constructing approximately one mile of concrete median barrier on Vasco Road with widening of approximately 6,900 linear feet of roadway; widening of one single span bridge (length 113 feet); constructing drainage, stormwater and erosion control facilities; constructing wildlife crossing systems, directional fencing, and Kit Fox and Tiger Salamander jumpouts, constructing retaining walls including mechanically stabilized earth walls and soil nail walls. The State Route 4 Bypass Authority advertised the project the week of August 3 and will open bids in mid-September.

The project should be awarded in October 2026, and construction is anticipated to begin in mid-February 2027.

To learn more, visit www.contracosta.ca.gov/Vasco-Road-Safety-Improvements-Project

About Contra Costa County Public Works Department:

The Contra Costa County Public Works Department (CCCPWD) is responsible for the maintenance and operation of over 650 miles of roads, 79 miles of streams and channels, and over 150 County buildings. CCCPWD services include parks and recreation, sandbag distribution, flood control, road and facilities maintenance, and storm water management. CCCPWD operates two airports, Buchanan Field Airport in Concord, and Byron Airport in Byron. For more information about CCCPWD, please visit us at: www.cccpublicworks.org

Vasco Road Crashes Heat Map

Editors Notes:

Marsh Creek Road / State Route 4 and Vasco Road Intersection: The heatmap at this location shows 1 fatal crash at the intersection and 1 severe injury crash on the intersection approach. There are less collisions here overall than the other two intersections.
Walnut Boulevard and Vasco Road: The heatmap at this location shows 3 fatal crashes and 1 or more severe injury crashes at the intersection and on the northern approach to the intersection. The intersection has a high concentration of both injury and property damage only crashes.
Camino Diablo and Vasco Road: The heatmap at this location shows more than 8 severe injury crashes and 4 fatal injury crashes on the approaches to the intersection. The intersection has a high concentration of both injury and property damage only crashes.
Vasco Road Corridor South of Camino Diablo: Vasco Road segment between Frisk Creek Bridge and the Alameda County line with Contra Costa County shows three severe injury crashes but a lower density overall of crashes compared to intersection locations.

OTS Crash Rate Comparison by County

The California OTS provides City and County level traffic data statistics to allow comparison between Cities of similar size and Counties as a whole. Contra Costa County in 2023 ranked 57th out of 58 Counties in the number of fatalities and injuries. This means that 56 other counties had more serious crashes based on total observed crash counts and the population of the County. Table 4.2 below provides a snapshot of 2023 rankings for Contra Costa County

Vasco Crash History

An analysis of collision trends along Vasco Road was completed using five years of collision data from SWITRS for the period from January 1, 2019 through December 31, 2023. SWITRS/CCRS is a database that collects and processes data gathered from a collision scene. A five-year analysis is consistent with HSIP and other similar federal and state guidelines and includes the most recent complete dataset available. During this period a total of 211 crashes were reported along Vasco Road from Marsh Creek Road to the southern Alameda County Line. There are no recorded bicycle or pedestrian collisions along the Study corridor within the five-year analysis period.

Crash by Year and Severity
Collisions are classified by the severity documented in police reports from the parties involved. Severity categories include collisions involving fatality, severe injury, visible (but not severe) injury, complaint of pain injury, and property damage only (collision resulted in only damage to the vehicle or other property). While the focus and goal of the corridor safety study is on reducing to zero the number of serious injury and fatal collisions also known as killed or severely injured (KSI), other factors including property damage only collision data are included in the data analyzed to provide a comprehensive picture of all potential safety hazards along the corridor. For the five-year analysis period, the number of crashes by severity are listed by collision year in Table 4.3 and graphically in Figure 4.2 provides a comparison of fatal and injury collisions for the Vasco Road Study corridor as compared to Contra Costa County and the state as a whole between 2019 and 2023. Table 4.5 aggregates the comparison for five-year collision data into a single number. The data shows that twenty-five percent (25%) of Vasco Road crashes are fatal and injury crashes as compared to Contra Cosa County at fifteen percent (15%). This is still less than California, which has approximately thirty-nine percent (39%) of crashes causing at least visible injury.