The Mare Island Causeway Bridge is located on the Napa River in the center of the Causeway, which crosses the Mare Island Strait at mile 2.8, Vallejo. The Bridge is 165 feet long and 48.5 feet wide. It provides crossing for vehicular, pedestrian and rail traffic. Minimum Clearance (Span down) 12.4 feet (based on High High Mean Water) Maximum Clearance (fully raised) 99.7 Feet (based upon High High Mean Water, 87.3 feet maximum lift height plus 12.4 feet distance to water) Hours of Operation The Mare Island Causeway Bridge is staffed with an on duty Bridge Operator who will open the bridge on signal between the hours of 9:00 A. M. and 7:00 P. M., seven days/week, including Holidays. The bridge is unmanned during the hours of 7:00 P. M and 9:00 A. M. but can be opened by calling (707) 648-4313. Two (2) hours advanced notice is required during this after hours time period. Communications During hours of operation you can request a Bridge opening in the following manner: By Sound Signal--Sound signals can be made by whistle, horn, megaphone, hailer or other device capable of producing the described signals loud enough to be heard by the Bridge Operator. To request an opening, provide one prolonged blast followed by one short blast. If we are able to open, we will respond in like manner. If we cannot open immediately, we will sound five short blasts in rapid succession. By Visual Signal--raise and lower a white flag vertically or a white, amber or green light vertically. By Radio--call us on Marine Radio Channel 13 (156.650 MHz). By Telephone--call the Bridge Control Room at 707-562-3556. We are regulated by: Eleventh Coast Guard District Bridge Section   Mare Island Causeway Bridge Building 50-6 Coast Guard Island Alameda, California 94501-5100 (510) 437-3514