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been updated. The following table compares the demand values included in the 2015 UWMP to
those currently estimated:

Annexing Development 2015 UWMP Estimate Current Estimate
Potentially Using BVRRB Supplies (AFY) (AFY)
Legacy 2,500 2,500
Tesoro 500 389
Tapia 575 489
Total 3,575 3,378

As discussed above, the 2015 UWMP demand estimates incorporated demands for the
proposed Legacy, Tesoro and Tapia annexations. The conclusion reached in the 2015 UWMP
was that assuming the water supply portfolio in the UWMP, the water supplies exceeded
demands (including potential demands for annexing areas) at buildout. These results are
summarized in the table below:

Average/ Single 4-Year 3-Year
Supply Source
Normal Dry-Year Drought Drought
Existing Groundwater 31,545 40,215 36,175 35,875
Existing Recycled 450 450 450 450
Existing Imported 70,707 22,087 45,177 33,167
Bank/Exchanges 7,950 7,950 7,950
Future Groundwater 10,230 20,335 21,875 21,325
Future Recycled 9,604 9,604 9,604 9,604
Future Bank/Exchanges 22,000 22,000 22,000
Total Supply 122,536 122,641 143,231 130,371
Demand w/Active Conservation 93,900 103,300 103,300 103,300
Surplus 28,636 19,342 39,931 27,071

As supplies substantially exceed demands for the scenarios in the 2015 UWMP, staff concludes
that sufficient BVRRB supplies will exist for the proposed Tapia Ranch Project.

Additionally, in November 2017, staff updated its Water Supply Reliability Plan. This report is
available using the following link: http://yourscvwater.com/wp-content/uploads/2018/06/2017-
Water-Supply-Reliability-Plan-Update_FINAL_110117.pdf. That report analyzes the existing
water supply portfolio along with three alternative scenarios for the study period of 2017 through
buildout in 2050 as described below:
 Base Scenario: Based on 2015 UWMP demand, supply, and storage program
assumptions. This includes planned increases in recycled water, conversion of
alluvium groundwater use from agricultural to municipal use, and dry-year increases
in Saugus groundwater pumping.

 Scenario A: Similar to the Base Scenario, but includes SWP supplies anticipated to
be available with proposed California WaterFix facilities.

 Scenario B: Moderate supply reductions relative to the Base Scenario with a
reduction in SWP supply reliability and reducing Saugus extraction to 20,000 AFY
during years where SWP supplies are significantly less than average, not exercising

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