San Ramon City Council
Ramp Metering Memorandum of Understanding
Presentation
August 11, 2026
Item No. 9.1.
I-680 – The Problem
Source: San Francisco Chronicle, April 20, 2026, from Caltrans Data Source: Google Maps, retrieved April 20, 2026
Why Ramp Metering?
• Regulates the flow of traffic entering the freeway
• Smooths out traffic flows
• Discourages off-ramp to on-ramp cut through traffic
• Reduces crashes caused by traffic merging onto freeway • Reliable and efficient travel on freeways will reduce need to cut through city streets
• Improve system efficiency without widening freeway - consistent with new SB 743 policy of reducing Vehicles Miles Traveled (VMT) I-680 Ramp Metering Projects
• Caltrans Adaptive Ramp Metering
(ARM)
- SB I-680 & NB I-680 from Burnett Avenue to
I-780 & other ITS elements
- Funded by State Highway Operations and
Protection Program (SHOPP)
➢ Cost and scope sharing for
efficient delivery
➢ Performance Evaluation
• CCTA – Innovate 680 Coordinated
Adaptive Ramp Metering (CARM)
- Partner with Caltrans for Demonstration
- Initial Phase NB I-680 from Alcosta Blvd to
Burnett Avenue
- Funded by local, state and federal funds
CCTA Innovate 680 Projects
Express Lane Completion
Part-time Transit Lanes
Automated Driving Systems
Advanced Technologies
• Coordinated Adaptive
Ramp Metering (CARM)
• Coordinated Adaptive Traffic
Signals (CATS)
Shared Mobility Hubs
Mobility-as-a-Service
Innovate 680 Advanced Technologies - CARM
• Achieves several Innovate 680 system management strategies:
• Primary network/corridor optimization tool in Managed Freeways • Avoids costly capacity expansion
• High operational benefits at lower costs
• Consistent with current state policy for reducing induced VMT https://youtu.be/dvLWB01BM8I?si=uTZD1tR8dMWUaQCs
Complete
Express
Lanes
TDM Using
Innovative
Tools
Prepare
Corridor for
the Future
Operational
Innovative
Connections
First
Last
-
-mile
and ✓
Strategies
Cool Corridor
“Hot Spots”
✓
Shoulder
Bus on
✓
Caltrans I-680 ARM Project
• MTC and Caltrans have implemented ARM on around 300 freeway onramps (I-80, I-880, and SM/SCL-101) and SFOBB in Bay Area • MTC and Caltrans are expanding the ARM coverage for major corridors, including I-680, SCL-237, SR-4, SCL-85, MRN-101, and SOL-80 - Does NOT activate based on Time of Day
- Proactively changes ramp metering rates upon potential traffic bottleneck forming - Turns on and off automatically for handling crashes
- Optimizes ramp metering rates based on mainline traffic conditions on the freeway https://mtc.ca.gov/operations/programsprojects/freeways/adaptive-rampmetering Caltrans ARM: US-101 and I-880
Caltrans ARM: US-101 Performance Evaluation
Whipple Ave (Redwood) to Harney Way (Brisbane)
Caltrans ARM: I-880 Performance Evaluation
I-280/I-880 Interchange (San Jose) to West Grand Ave (Oakland) Innovate 680 CARM Project
• CCTA - Caltrans partnership to implement CARM along a 20-mile portion of NB I-680
• 3-year demonstration of CARM at 16 on-ramps
• Next generation of ramp metering
- Expands the adaptive capabilities of ARM with more real-time vehicle detection and system monitoring along the corridor
- Coordinates across all ramp meters to control the traffic entering the freeway to optimize flows and reduce congestion
- Ability to coordinate with adaptive traffic signals systems • I-680 will be the second use of CARM in CA after I-15 in Riverside County (Going live in End of May)
I-15 CARM Project Website:
https://smartfreeway.org/virtual-room/index.html
12 Real Time Detection – On Ramps and Mainline
Innovate 680 CARM – STREAMS® Platform
STREAMS Freeway Operations Dashboard for RCTC I-15 Smart Freeways Crow Canyon Road/Northbound
NO SCALE
Bollinger Canyon Road/Northbound
NO SCALE
I-680 Ramp Metering MOU - Purpose
• Collaborative Approach on Ramp Metering Implementation • MOU requested by CCTA and local agencies
• Multiple reviews and 1:1 Meetings with local agency technical staff • Foundation of ramp metering implementation, policy and roles/responsibilities • Framework for Selection of Key Performance Indicators and Communication • Stakeholder Coordination/Governance Structure
I-680 Ramp Metering Governance Structure
I-680 Ramp Metering O&M Procedures (RMOMP)
• After MOU → RMOMP Development
- A “Users Manual”
- CCTA, Caltrans & local agency staff with multiple review cycles - Outlines ramp metering operations, including incident management, maintenance responsibilities
- Ramp metering performance and reporting requirements
- Protocols for stakeholder communications
- RMOMP to be completed by early 2028, to be updated as needed - Informs Caltrans/CCTA O&M COOP Agreement
I-680 Ramp Metering Implementation Schedule
• Caltrans ARM
- Construction: November 2025 to Late 2028
• Innovate 680 CARM
- Currently in Final Design
- Construction anticipated: Early 2027 to Late 2028
• Both ramp metering systems are expected to be fully operational by early 2029 - Some signals may initially rest on green until the entire corridor is ready for metering Caltrans ARM
CCTA Innovate 680 CARM
2026 2027 2028 2029 2030 2031
CONSTRUCTION
CONSTRUCTION
OPERATION
DESIGN OPERATION
Questions/Comments