Page 17 - Beaumont Basin Watermaster

Beaumont Basin Watermaster
2013 Reevaluation of the Beaumont Basin Safe Yield 3-Apr-15

2.5 Surface and Groundwater Monitoring Facilities

Stream flow data used for this study were obtained from a USGS stream gage on Little San
Gorgonio Creek and manual gaging of San Timoteo Creek (see Figure 10). Little San Gorgonio
Creek surface water flows were measured by the USGS from 1948 to 1985. Surface water flow
within San Timoteo Creek has been measured by YVWD on a weekly basis from 2002 to 2012.

Surface water flow in San Timoteo Creek is sustained from treated wastewater discharges to
Cooper’s Creek by the City of Beaumont and groundwater discharge to the creek channel. The
primary wastewater discharge point is in Cooper’s Creek adjacent to the wastewater treatment
plant (WWTP) (see Figure 10). The second discharge point is in a small drainage north of the
WWTP. The current WWTP was constructed in 1994 which replaced the original plant built in
1929. Monthly wastewater discharge data were available from the City of Beaumont for 2011
and 2012.

Groundwater level measurements are monitored in both pumping and non-pumping wells located
throughout the Study Area (see Figure 9). Wells with static groundwater levels used for this
study are summarized in Appendix B. Hydrographs from selected monitoring wells were used as
a basis for calibrating the groundwater flow model (see Section 5.9).

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