Page 29 - Beaumont Basin Watermaster

Section 3
Water Quality Conditions

finding. Subsurface recharge across the Banning Fault was investigated as part of the Safe
Yield of the Basin determination study, completed in early 2015.

Deliveries of imported water by the SGPWA to the Little San Gorgonio Creek Spreading
Ponds began in August 2003; the agency has since recharged a total of 10,508 ac-ft
averaging 808 ac-ft/yr. Deliveries in CY 2013, at 881 ac-ft, were less than half of the amount
spread in CY 2011 and CY 2012. Deliveries in CY 2014 through CY 2018 were basically non-
existent as less than 44 ac-ft were spread in those five years combined. Under Resolution 17-
01, adopted on June 7, 2017, the SGPWA entered into a storage agreement with the
Beaumont Basin Watermaster to spread up to 10,000 ac-ft of imported water in the Beaumont
Basin subject to certain conditions. As part of their application, the SGPWA is in the process
of completing the construction of their own spreading facilities in the southwest corner of
Brookside Avenue and Beaumont Avenue as described earlier in this section.

3.3.2 Recycled Water Recharge

Prior to March 2010, Beaumont’s recycled water from Wastewater Treatment Plant No. 1 was
discharged at Discharge Point No. 1 (DP-001) in Cooper’s Canyon where it infiltrates into the
San Timoteo Management Zone and outside the Beaumont Basin. Starting in March 2010,
Beaumont began deliveries of recycled water to Discharge Point No. 7 (DP-007), located
along an unnamed tributary of Marshall Creek, as shown in Figure 3-3. It is believed that a
portion of the recycled water discharged at this location reaches and recharges the Beaumont
Basin. It should be noted that the City of Beaumont decided to ceased deliveries to DP-007 in
the Fall of 2015.

In CY 2018, the City of Beaumont discharged an estimated 3,799 ac-ft of recycled water at
DP-001 in Cooper’s Canyon. Recycled water discharges were approximately four percent
higher than in CY 2017. Monthly discharges at DP-001 varied slightly from a low 3.28 mgd in
February to a high of 3.51 mgd in August; the average for the year was 3.39 mgd. Monthly
recycled water discharges by the City of Beaumont since 2007 are summarized in Table 3-5.

3.3.3 New Yield Stormwater Recharge
Before accounting for any new yield resulting from the recharge of local surface water, not
initially considered as part of the Basin Safe Yield, Watermaster needs to develop a
methodology to quantify and credit the New Yield to the party that creates the new recharge.
According to Part VI Paragraph 5.V of the Judgment, Watermaster shall make an independent
scientific assessment of the estimated new yield created by each proposed project. It is our
understanding that the City of Beaumont has been recharging local waters at various locations
in the Basin and would like to receive credit for the New Yield developed. For Beaumont to
receive credit however, Watermaster will need to develop the methodology to compute and
credit the New Yield dating back to the Judgment inception in February 2003 or since delivery
of flows began, whichever is latest.

Beaumont Basin Watermaster 2018 Annual Report – DRAFT - February 2019 3-7