Daly City – Starting October 21, 2008, drivers entering northbound I-280 from the Sneath Lane, San Bruno Ave, Westborough Blvd, Hickey Blvd, and Serramonte Blvd on-ramps will see the metering signal lights turned on. Metering lights at the on-ramps will be set for green and red cycles during afternoon peak commute hours when traffic is heaviest on this segment on the freeway in the northbound direction. Hours of operations will be Monday through Friday between 3:00 PM and 8:00 PM. One vehicle per green cycle will be permitted to enter into the freeway. As a result, “platoon” of vehicles entering the freeway will be broken up, thereby reducing the conflict of merging and weaving at and near the entrance areas. It will allow traffic to flow better. However, drivers will have to wait for their turn before getting on the freeway. As a result, overall travel time along the freeway will be reduced.

Turning on the metering lights are being done in stages in San Mateo County. Starting in January 2007, metering lights were turned on along the northbound and southbound directions on US 101 between Hillsdale Blvd and University Ave, during both morning and afternoon commute hours. Significant travel time saving was recorded for that segment of the freeway.

Traffic congestion is severe along I-280 between San Bruno and Daly City in the northbound direction during afternoon commute hours. The City/County Association of Governments (C/CAG) of San Mateo County, representing all twenty cities plus the County, along with its partner agencies, concluded that metering lights will be an effective tool to manage traffic congestion. The partner agencies include Caltrans, local cities, the County, San Mateo County Transportation Authority (SMCTA), and the Metropolitan Transportation Commission (MTC).

Although traffic congestion is also severe in the southbound direction during morning commute hours, metering equipment are not available in the southbound direction yet. C/CAG, MTC, and Caltrans are working on funding a project to install equipment in the southbound direction.

Sue Lempert, a Commissioner representing the cities of San Mateo County at the Metropolitan Transportation Commission (MTC) said "Ramp metering will help congestion relief by increasing throughput capacity of the freeway in a very cost efficient manner. C/CAG found a very smart way to implement ramp metering by putting in ‘end-of-queue’ detectors to avoid vehicles from backing up onto local streets." The end-of-queue detectors Lempert referred to are installed at the entrances to each of the on-ramps to detect when the queue is longer than the length of the on-ramp itself, meaning backs up onto local streets. The end-of-queue detectors will trigger the metering system to adjust the green/red cycle time to a faster rate until the presence of a queue on local streets is off the detector.

C/CAG has investigated the ramp metering issue for several years now. A Ramp Metering Technical Committee, with representatives from involved cities, Caltrans, and C/CAG, has been set up to review and approve all technical issues regarding ramp metering. In addition, “before” and “after” traffic condition monitoring will be set up to monitor local street traffic to preserve the local street traffic operation.

To provide advance notice to drivers, the metering lights will remain all-green during the metering hours one week before the starting dates. For information on ramp metering, the public may call the Caltrans hotline at (510) 286-4531.

Daly City 280 Ramp Meter FAQ