By Elizabeth Zach, RCAC staff writer
Because of excessive groundwater extraction, subsidence—the sinking or settling of the ground’s surface—is dragging rural Yolo and Colusa counties in California downward.
In one notable case, the town of Arbuckle in Colusa County, sank more than two feet in nine years between 2008 and 2017, according to the Los AngelesTimes.
Hydrologists attribute the sinkage to drawing down the Sacramento Valley’s groundwater during California’s drought between 2012 and 2016.
Subsidence can damage roads, levees, pipelines and aquifers. Roads may crack and canals may buckle and warp. In these cases, water operators must decrease the flow of water to sunken aqueducts so that it doesn’t overflow the banks.