This week the California Department of Transportation (Caltrans) set on-ramp meters on eastbound and westbound State Route 4 to solid green during commute times. The change is intended to alert drivers to upcoming changes to the on-ramp metering system scheduled for later this month.
Ramp metering uses traffic signals to manage on-ramp flow onto freeways. It is intended to improve the safety of vehicle merging and the flow of traffic on the highway.
In the first stage of ramp meter activation in Contra Costa County, ramp meters were activated on westbound State Route 4 from Sand Creek Road in Brentwood to Alhambra Avenue in Martinez. Beginning Tuesday, October 10, on-ramp meters were set to solid green during commute times to alert drivers to the new driving condition. On Tuesday, October 17, ramp meters will begin cycling through red and green during commute hours, from 5 a.m. to 10 a.m.
Drivers entering Route 4 where ramp meters are activated should stop at red and wait until the metering light turns green to the freeway. Caltrans will continue to monitor traffic conditions.
In the next stage, Caltrans will activate ramp meters on eastbound Route 4 from Alhambra Avenue in Martinez to Lone Tree Way (East) in Brentwood. Beginning Tuesday, October 10, on-ramp meters were set to solid green during commute times to alert drivers to the new driving condition. Starting Tuesday, October 31, ramp meters will cycle through red and green during commute hours, from 2 p.m. to 8 p.m.
Many of the on-ramps in Contra Costa County have a carpool lane marked with a diamond. The carpool lane restriction for on-ramp is 24-hours per day, 7 days a week. Caltrans Ramp Metering Information Line is (510) 286-4531 or follow on Twitter at https://mobile.twitter.com/CaltransD4. Click on the link below for the full statement from Caltrans on this metering signal change.
Caltrans Advisory On Ramp Signal Changes