US-101 adaptive ramp metering implementation in marin and sonoma counties this project upgrades the existing local responsive ramp metering to adapti

The Federal Highway Administration awarded the California Department of Transportation (Caltrans) $281,450.91 under the Congestion Mitigation and Air Quality Improvement Program (CMAQ, CFDA 20.268) on January 27, 2026, to upgrade existing local responsive ramp metering to adaptive ramp metering (ARM) along the US-101 corridor in Marin and Sonoma Counties, improving traffic flow and safety.

The project runs through December 31, 2029, and is performed in California. The CMAQ program funds transportation projects and programs in nonattainment and maintenance areas to reduce congestion and improve air quality for ozone, carbon monoxide, and particulate matter. Funds are available for obligation for three years after the end of the fiscal year in which they are authorized.

Project description

US-101 adaptive ramp metering implementation in marin and sonoma counties this project upgrades the existing local responsive ramp metering to adaptive ramp metering (arm) along the US-101 corridor in marin and sonoma counties to improve traffic flow and safety. (TC).