CC - Agendas - City Council - WORKSHOP - 10/28/2008

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Home construction has dropped considerably, and is expected to remain below projections for at least a few years (many experts say it will take at least five years to return to "normal"). However, all of the computations used above are based on the "normal" yearly water allocations. Times have changed. We need to consider whether our previously -planned schedule for Big Chino water needs to be changed. SAFE YIELD We should not ignore our responsibility to reach Safe Yield by 2025. Prescott's Reasonable Growth Initiative, passed in 2005, requires all effluent from developments in large annexation areas go to Safe Yield. We should also apply all water saved through conservation to Safe Yield. We have 17 years to implement other components of a Safe Yield plan. As mentioned above, of the alternate water available now and applied for, 1296 acre-feet is needed to serve all vacant non -watered lots in the city limits at existing densities. The bulk of the rest could go to annexed areas covered by provisions in the initiative. Approximately 2000 to 2500 acre-feet will be available to serve annexed areas (including the already annexed Fann area). Assuming new construction will devote less water to exterior use (as is the trend), Prescott can estimate an effluent amount around 65% of the developments' water use. So using the available and applied -for alternate water supplies, Prescott could expect to contribute approximately 1300 to 1600 acre-feet per year to permanent recharge to help our AMA reach Safe Yield. In addition, if the city establishes a policy that all water conservation savings will be allocated to Safe Yield, then the amount of water we pump in the AMA can be reduced considerably. An achievable goal by 2025 of a 22% per capita water reduction (as in Prescott consultant Herb Dishlip's Safe Yield scenario) would be a major step towards Safe Yield. In September, Prescott Water Management Analyst, Connie Tucker, reported that in just the last four years Prescott has already achieved a 7% reduction in groundwater use per residential unit. In 2025 we may have 70,000 people (33,000 homes) dependant on both AMA groundwater and recharged water. If those homes and associated non-residential use have a reduced demand 22% below the .35 acre-feet per home that ADWR allows, the reduction in pumped water will be 2541 acre-feet per year. Just the above two measures could contribute a total of over 3800 acre-feet towards Safe Yield. Prescott's share of our AMA's 11,000 acre-foot overdraft is