GSP Annual Report
5-021.69 WYANDOTTE CREEK
2021 (OCT. 2020 - SEP. 2021)
Single Annual Report
GSP Annual Report Information Comments
03/30/2022 4:25 PM
2021 (OCT. 2020 - SEP. 2021)
Single Annual Report
A Groundwater Extraction
Total Groundwater Extractions (AF)
46,333
Water Use Sectors
633
0
44,600
0
0
0
1,100
Rural Residential
B Groundwater Extraction Methods
Meters
633
Direct
5-10 %
Metered Municipal Wells
Metered connections maintained by California Water Service and Thermalito Water and Sewer District
Electrical Records
0
Land Use
44,600
Estimate
20-30 %
Land use estimates were used with locally derived crop coefficients and irrigation efficiencies. Groundwater pumping estimated after precipitation and surface water deliveries were accounted for.
Typical accuracy for crop coefficient and reference ET methodology.
Groundwater Model
0
Other
1,100
Estimate
10-20 %
Rural residential groundwater extraction is estimated based on the California Water Service Company 2020 Urban Water Management Plan 2020 usage of an average per capita water use of 184 gallons per capita per day. Population data from the 2020 census was coupled with parcel data to identify total population not serviced by municipal supplies.
Uncertainties arise from population estimates and gpcd estimates
C Surface Water Supply
Total Surface Water Supply (AF)
33,202
Methods Used to Determine
Methods include measured diversions by water suppliers and estimated diversions based on historic State Water Resource Control Board eWRIMS (Electronic Water Rights Information Management System) data for total diversions. Surface water delivery estimates are based on historic deliveries in the area that have occurred in dry and critical years.
Water Source Types
0
29
0
33,173
0
0
0
0
D Total Water Use
Total Water Use (AF)
79,535
Methods Used to Determine
Methods used are a combination of estimates based on land use and population/per capita water use, metered municipal/industrial water use, measured diversions, and estimates based on historic water rights data for dry and critical years.
Water Source Types
46,333
33,202
0
0
0
Water Use Sectors
11,811
0
66,624
0
0
0
1,100
Rural Residential (private domestic wells)
E Change in Storage
Method used to calculate change in storage
Estimated change in storage was based on groundwater level change from spring 2020 to spring 2021 at each RMS well, a representative storage coefficient of 0.1, with Thiessen polygons defining a representative area for each RMS well. The representative storage coefficient was established by roughly calibrating estimated change in storage based on changes in observed water levels (i.e. calculated using water level data, representative area, and storage coefficient parameter) with estimated change in storage outputs from the Butte Basin Groundwater Model as reported in the GSP to aggregate characteristics across all zones of the principal aquifer system. A total of 20 pairs of concurrent annual storage changes from both of these methods (i.e., 1. groundwater level change method used in this report, and 2. modeled storage changes from the GSP) from 1999 through 2018 were used for calibration.
