Groundwater levels are measured in the YCFCWCD 150 well network each spring and fall. The graph above show the average groundwater level of all the wells. This fall’s 2018 levels dropped, as expected each fall. In the spring, they will recover again. Hence the saw-tooth pattern seen in the hydrograph. In the short term, the amount of drop or recovery depends on the winter rains. If there is more rain, there is less drop and more recovery. If it is dry, groundwater levels drop more and recover less. In the long term, increased pumping from wells can overcome recharge rates and levels could fall year after year, a situation called overdraft. The activities of the YSGA hope to avoid overdraft.
Average fall 2017 groundwater level in Yolo County is 43 feet depth to water. Groundwater levels normally drop after the long summer with no rain. Recovery after the recent drought continues. Groundwater levels are in good shape in most areas of the County.
Each spring and fall, the YCFCWCD measures the groundwater in approximately 150 wells. The sawtooth shape of the line in the graph above is due to the spring/fall fluctuation each year, high in spring, low in fall. This year, spring measurements occurred around the first week of April.
This spring 2016’s measurements show the groundwater is slightly higher than last spring. Even though groundwater is improving, it is still low due to the drought.
Each spring and fall, the YCFCWCD measures the groundwater in approximately 150 wells. The sawtooth shape of the line in the graph above is due to the spring/fall fluctuation each year, high in spring, low in fall.
This fall 2015’s measurements show the groundwater is slightly higher than last fall. Water levels are higher this year because of the availability of surface water from the Cache Creek system. This year about 25% of a full amount was available, while last year in 2014, zero water was available from Cache Creek. So there was less groundwater pumping this past summer, which is reflected in the higher groundwater levels this fall. Even though groundwater is in better shape today than in 2014, it is still low due to the drought.
State Well NumberingA nice article on how the Dept of Water Resources assigns a unique ID to wells, it’s like a vehicle license plate. However, only a fraction of existing wells get a SWN. Many wells do not have a SWN.
The District’s Water Resources Technician, Aaron Gurecki, has been out all week measuring groundwater levels. We will quality check the data and results will be available next week.
There are 150 wells in the network, about 100 have been monitored since the 1950’s. We have a good history of our aquifer’s response to drought.
Max Stevenson
Asst. General Manager – Resources
Yolo County Flood Control & Water Conservation District
530-662-0265 office
530-681-6004 cell
www.ycfcwcd.org
The forum for groundwater information and Sustainable Groundwater Management Act (SGMA) planning and implementation.
