MARE ISLAND, CA– A magnitude 6.0 earthquake struck 4 miles northwest of American Canyon (Napa County) at 3:20 a.m., according to the U.S. Geological Survey.—UPDATES The HWY 37 exit to Westbound Sonoma Blvd has been damaged and is closed as of 4:15 AM due to reported buckling of the roadway–Reports of some minor damage to HWY 37 Bridge over the Napa River, but it remains open. Reports of broken water sprinklers inside the US Forestry HQ Building on the south end of the island was reported at 5:30 AM. The facade of the historic 1145 Nimitz building was severely damaged and the roadway is closed to traffic. A City of Vallejo official reported that one of the 2 waiter lines serving Mare Island has been broken an is currently shut off. Water services still remain operational thanks to a second southern line.