City of Morgan Hill Water System Master Plan 2017

Table 3.3 Planning and Design Criteria Summary Water System Master Plan City of Morgan Hill

PRELIMINARY

Design Parameter

Criteria

Supply

Supply to Meet Maximum Day Demands with Firm Capacity

Firm Capacity excludes largest well for possible maintenance and emergency

Largest well is currently Diana #2 at approximately 1,500 gpm

Assume Future Well Capacities at 800 gpm each.

Storage

Total Required Storage = Operational + Fire + Emergency

Operational Storage

25% of Maximum Day Demand

Emergency Storage

25% of Maximum Day Demand

Fire Storage

Residential = 0.18 MG (1,500 gpm for 2 hours)

Commercial = 0.30 MG (2,500 gpm for 2 hours)

Industrial = 0.63 MG (3,500 gpm for 3 hours)

Pump Stations

Meet Maximum Day Demand with largest unit out of service

Hydropneumatic systems to meet Maximum Day Demand plus fire flow

Pressure Reducing Valves

PRVs should be designed to meet the greater of:

Peak Hour Demand, or Maximum Day Demand + Fire Flow

Service Pressures

Maximum Pressure

100 psi

Minimum Pressure (during Maximum Day)

40 psi

Minimum Pressure (during Peak Hour)

35 psi

Minimum Pressure for New Development 1 (during Peak Hour)

40 psi

Minimum Residual Pressure (during Fires)

20 psi

Demand Peaking Factors

Maximum Month Demand

1.75 x Average Day Demand

Maximum Day Demand

2.00 x Average Day Demand

Peak Hour Demand

3.00 x Average Day Demand

Fire Flows

Residential

1,500 gpm for 2 hours

Commercial

2,500 gpm for 2 hours

Industrial

3,500 gpm for 3 hours

Urban Water Use Targets 2015 Urban Water Management Plan

Existing Coefficient

199 gpdc

2015 Interim Target

179 gpdc

2020 Target (20% Conservation)

159 gpdc

1/14/2016

Note:

1. Source: California Department of Public Health Title 22, Chapter 16, Article 8 "Distribution System Operation"