Riders on crowded BART trains serving San Mateo County stations will see some relief beginning today. SamTrans, the agency responsible for funding the operation of the extension to San Francisco International Airport and Millbrae, is adding extra trains to the morning and evening commute, as well as extra cars to two of the most popular morning trains.

During the morning peak, eight Richmond trains will serve the Colma station. In the afternoon, nine of the Richmond trains will serve Colma. This is in addition to the Dublin/Pleasanton line, which currently serves all stations on the extension.

This change will give riders less crowded trains and more frequent service. The number of trains serving the Colma station will double during the commute, from the current service of one every 15 minutes to two.

In addition, extra cars will be added to two popular early morning trains. The trains leaving the Millbrae Intermodal Station at 6:31 a.m. and 6:46 a.m. will be increased from four to eight cars.

Staff will continue to monitor the extension on a daily basis and make adjustments as needed. SamTrans initiated the changes to alleviate crowding on some trains.

In 2004, ridership on the extension, which includes the Colma, South San Francisco, San Bruno, Millbrae and SFO stations, was 140,765 during the week following the Labor Day holiday. This year, ridership during the same week was 148,221, an increase of 5.3 percent over the previous year.

The San Mateo County Transit District is a partner with BART on the San Mateo County service is responsible for the operating costs on the extension. While ridership on the extension is growing, it has yet to meet initial projections, resulting in a significant and unanticipated ongoing budget deficit.