1971 – The giant garter snake was listed as a state endangered species under the California Endangered Species Act.
October 20, 1993 – The San Francisco garter snake was listed as a federally threatened species under the U.S. Endangered Species Act.
1999 – A draft recovery plan was published for the giant garter snake.
December 16, 2008 – The Center filed notice of intent to sue the U.S. Bureau of Reclamation for approval of water transfers that would eliminate giant garter snake habitat in Yolo County, California.