14 ATTACHMENT 1 EXHIBIT C - Laserfiche WebLink

Water Shortage Contingency Plan 4.5.1 Interrupted Supply from Zone 7 THE CITY OF PLEASANTON. If imported water deliveries are interrupted, Zone 7 plans to meet its current water demands with existing facilities using groundwater and Zone 7's share of water stored in Lake Del Valle. The City and other retailers with groundwater pumping capacity may be asked to increase their groundwater pumping, if possible. In this case, Zone 7 would declare a water shortage emergency in coordination with the City and its other retailers, who would then put into effect their WSCPs and associated voluntary and mandatory water consumption reductions. Zone 7 has emergency generators (both portable and dedicated) at strategic locations in preparation for any regional power outage. These generators would allow both the Del Valle Water Treatment Plant and the Patterson Pass Water Treatment Plant to continue operating even under a power outage. Assuming no interruptions in surface water supply, Zone 7 would be able to provide service to all treated water contractors. If warranted by demand, Zone 7 would also operate groundwater wells, which have either a dedicated generator in place or have the necessary hook-ups to receive power from a portable generator. If the power failure were to occur during the high -demand summer season, Zone 7 may be unable to meet hourly peak demands throughout the transmission system. Zone 7 would work closely with the City and other retailers to manage demands to minimize impacts. 4.5.1.1 Unavailable SWP Water There could be an emergency situation where no water was available from the SWP. This could occur if the South Bay Aqueduct (SBA) was inoperable due to maintenance or damage from an earthquake. Water supplies from the SWP could also be limited or unavailable during a future drought. If no water were available from the SWP, Zone 7 would need to meet customer demand with groundwater and available local water stored in Lake Del Valle. The worst disruption to SWP deliveries would likely result from a moderate to a large earthquake, causing multiple Delta island levee failures and cessation of exports from the Delta of up to a year. Under this scenario and under current conditions, Zone 7 estimates that it would be able to make full deliveries to the retailers during non -summer months using a combination of groundwater and water stored in Lake Del Valle. During the peak demand of the summer months, however, Zone 7 will need to reduce deliveries to the retailers, including the City. Zone 7's analysis shows that Zone 7 has sufficient groundwater supply and pumping ability to serve the indoor water use needs of the service area over a one -year period; the availability of water supply for outdoor water use during the summer months will depend on the amount of water available in Lake Del Valle. Depending on timing and degree of recovery, the City might enact any of the stages of water shortage conditions discussed in Section 3.0. 4.5.1.2 Unavailable Zone 7 Water The City receives Zone 7 supplies at seven different turnout locations. If Zone 7 supplies are unavailable at one or more turnouts, Zone 7 supplies may still be available at the remaining turnouts. If the City's wells are not sufficient to meet demands, the City may also be able to obtain emergency supplies from its emergency interties with DSRSD. Depending on the availability of water from these sources, the City may need to enact various water shortage stages discussed in Section 3.0 to deal with a supply shortfall. 4.5.2 Area -Wide Electrical Power Failure During a prolonged electrical power outage, the City would continue to receive water from Zone 7. Zone 7 has emergency generators (both portable and dedicated) at strategic locations in preparation for a regional power outage. These generators would allow both the Del Valle Water Treatment Plant and the 12 City of Pleasanton N-e80-60-20-04-wP-R-e80-2020uwMP Last Revised: 05-05-21