Award-Winning Intelligent Transportation Solution For San Francisco-Oakland Bay Bridge in California
As one of the few options for commuters crossing the San Francisco Bay in California, 260,000+ vehicles per day funnel from 20-lanes into 5 lanes to traverse the 8 mile San Francisco-Oakland Bay Bridge (SFOBB).
We accepted the challenge to increase safety and decrease congestion by upgrading the bridge’s mainline metering system with an automated, one-of-a-kind intelligent transportation solution.
This new mainline system integrates advanced traffic controllers, vehicle detection sensors, cctv cameras and variable message signs, assessing traffic flow conditions in the highly congested approach to the bridge. The upgraded metering lights system uses a fuzzy logic algorithm that evaluates weighted parameters to assess real-time congestion levels, and reacts within minutes of a change in traffic conditions. The algorithm seamlessly considers several factors in determining when to activate the metering system and recommends when and how to adjust metering rates, including:
- General-purpose lane and HOV/transit demand
- Lane utilization imbalances
- Downstream congestion
- Cash vs Toll Lanes (FasTrak)
New field and central system equipment and traffic monitoring stations that are strategically incorporated in the SFOBB Toll Plaza improve the system’s response to both upstream and downstream real-time traffic conditions. And updated advanced transportation management system and controller software, hardware, and Intelligent Transportation System (ITS) devices improve traffic operations.
The automated metering system includes several layers of redundancies to maintain system performance in the event of emergencies or system failure. These redundancies protect communication infrastructure, servers, and networking devices, in addition to multiple operational facilities on both sides of the bridge.
The upgraded metering lights system incorporates multiple feedback loops, such as a performance measure dashboard that reports on real-time and historic performance measures. The fuzzy logic algorithm can be finetuned as new detectors are integrated into the system, and it can also be migrated to other regional toll bridges requiring mainline metering.
Solutions For The Future
We’re proud of this partnership between the Bay Area Toll Authority and Caltrans District 4 Bay Area that exemplifies a commitment to providing an efficient transportation system that enhances California’s economy and livability.
We’re also proud that this solution – which is one of only two of its type in the world –increases safety, decreasing congestion, and improves air quality. Thank you to the International Road Foundation for honoring this solution with a 2022 Global Road Achievement Award for Traffic Management and Intelligent Transportation Systems!