Borrego Springs Watermaster Releases Report on Revision of Sustainable Yield
Last updated 8/14/2024 at 1:53pm
The Watermaster’s Technical Advisory Committee (TAC) has completed recalibration of the Borrego Valley Hydrologic Model (BVHM) as part of Task 4 to Redetermine the Sustainable Yield (Recalibrated BVHM). This information will be the topic of discussion during the Ad-Hoc TAC meeting on Wednesday, August 14. The initial Sustainable Yield of the Valley was developed by USGS and extended by Dudek thru WY2016 to be 5,749 Acre Feet per Year (AF/YR). The TAC published at borregospringswatermaster.com, Hydrographs comparing actual water levels of 83 wells to simulated levels resulting from both the initial and revised hydrologic models and a series of figures that display the results of model calibration. The reports also provide a Preliminary Estimate of the revised sustainable yield which was revised up to 8,403 AF/YR, up 38% from the prior 5,749 AF/YR. The New sustainable Yield estimate only takes into account the Borrego Springs Subbasin, where the old model included Ocotillo Wells Subbasins as well. In addition, the New model uses a more recent period for calculating average return flows (WY1980 to 2022) where the old model used WY1945-2016.