City of Morgan Hill Water System Master Plan 2017

7.3 LOW PRESSURES ANALYSIS

The hydraulic model was also used to determine if the existing domestic water distribution system meets the City’s System Performance and Design Criteria for maximum day and peak hour pressures, as discussed in a previous chapter. During maximum day demands the minimum pressure requirement is 40 psi, while during the peak hour demand, the minimum pressure requirement is 35 psi. The hydraulic analysis indicated the City’s existing system performed reasonably well during under maximum day ( Figure 7.3 ) and peak hour ( Figure 7.4 ) operating conditions. The hydraulic model was also used to identify areas in the City’s existing domestic water distribution system that experience high pressure under maximum day demand conditions. The areas of high pressure are shown graphically on Figure 7.5 . Areas of high pressure may be more susceptible to pipeline breaks and ruptures. The City’s maximum desired pressure criterion is 100 psi. The areas experiencing high pressures are briefly described as follows:  Woodland Pressure Zone: Development near Rocky Ridge Road and Rolling Hills Road, east of the Woodland Reservoir experience maximum pressures between 150 and 225 psi. These developments are served by the Woodland storage reservoir, which has a base elevation of approximately 1,080 feet and serves developments with elevations as low as 630 feet.  Llagas Pressure Zone: Development along Llagas Road, east of Enderson Court, experience maximum pressures between 150 and 200 psi. These developments are served by the Glen Ayre Reservoir. These developments are served by the Llagas storage reservoir, which has a base elevation of 700 feet and serves developments with elevations as low as 360 feet.  Holiday Lake Pressure Zone: Development along Thomas Grade east of Dunne Avenue experience maximum pressures between 150 and 225 psi. These developments are served by the Holiday Lake Reservoirs, which have a base elevation of 960 feet and serve developments with elevations as low as 500 feet. 7.4 HIGH PRESSURE ANALYSIS

7.5 WATER SUPPLY REQUIREMENTS

The City’s existing domestic water system supply capacity is identified in this section. Additionally, this section identifies the additional supply capacity required to meet the supply requirement, and consistent with the City’s System Performance and Design Criteria.

7.5.1

Existing Supply Requirements

Existing supply requirements were identified for the City and are summarized on Table 7.1 . The City’s existing water supply requirement was based on the existing land use and recommended

June 2017

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City of Morgan Hill Water System Master Plan