Between 1914 and 1960 there were twelve damaging floods of the valley floor or about one flood every four years. Since 1960 damaging floods have occurred less frequently for several reasons, including better creek maintenance, construction of a concrete channel in Kentfield and Ross, and the fact that 14 out of the 38 years were relatively dry with rainfall between 42% and 75% of the average. Even so, the largest and third largest floods of record occurred during this time, in January 1982 and March 1983. The flood of January 3-5, 1982 was the largest on record and caused considerable damage in San Anselmo, Ross, Kentfield, and Larkspur. Flood water 4 to 5 feet deep flowed down Poplar and Kent avenues with enough force to move cars. On February 2, 1998, just as water began to come out of the channel at the Lagunitas Road bridge and at Granton Park, the rain eased up and the water level dropped. A flood on December 31, 2005 reached levels only slightly below those of the 1982 flood, and has spurred town and county officials to initiate an ambitious program to reduce future flooding. Many creekside homeowners have raised their houses to reduce damage from future flooding.
For more information:
History of Flood Management (110 KB)