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<br />TABLE 8 -6
<br />PROJECTED PEAK DAY DEMAND
<br />Year
<br />Estimated
<br />Population
<br />on the
<br />system
<br />Projected
<br />Per Capita
<br />Consumption
<br />(gpcd)
<br />Peak Day
<br />Demand
<br />2004
<br />13,161
<br />366
<br />4,815,000
<br />2005
<br />13,196
<br />336
<br />4,433,000
<br />2006
<br />14,043
<br />362
<br />5,082,000
<br />2007
<br />14,493
<br />423
<br />6,124,000
<br />2010
<br />17,550
<br />350
<br />6,142,500
<br />2020
<br />26,135
<br />275
<br />7,187,125
<br />2030
<br />34,208
<br />250
<br />8,552,000
<br />FIRE FLOW CONSIDERATIONS
<br />The Insurance Services Office (ISO) publishes a report that quantifies the magnitude and duration of fire
<br />suppression water requirements for individual structures, and summarizes these in a "Needed Fire Flow
<br />Batch Report ". These estimated water requirements are primarily for major commercial, industrial, and
<br />public buildings, and consider several factors including the size of the structure, exposure to adjacent
<br />structures, construction materials, occupancy types, stored materials, and other similar factors.
<br />Identification of these locations allows a more representative evaluation of the fire capacity of the
<br />distribution system because it is based on actual fire flow needs within the City.
<br />In the absence of ISO information, typical fire suppression needs are often set at 1,000 gpm for low
<br />density residential, 1,500 gpm for a medium density and estate residential, 2,000 gpm for high density
<br />residential (i.e., townhomes, quadhomes, apartment buildings, etc.), and between 2,500 -3,500 gpm for
<br />commercial, industrial, and institutional areas. Buildings which are provided with internal sprinkler
<br />systems usually have greatly reduced water flow requirements, depending on the structure rating. Most
<br />systems require only 500 -750 gpm for the sprinkler system and another 400 gpm for a hose stream.
<br />STORAGE REQUIREMENTS
<br />Water storage is provided in a municipal water system for three main reasons. The first is to provide for
<br />smooth pump operations, minimizing the frequent starting and stopping of large electric motors. The
<br />second reason is to provide reserve storage for emergency events, such as power outages, mechanical
<br />failure, and other events where the supply is unable to meet the instantaneous demand, or is lost
<br />altogether. The final reason is to provide sufficient equalization storage to supply the peak hour needs in
<br />excess of pumping capacity during a peak day event.
<br />Minimum storage requirements have been established by the "Ten States Standardsi1, which state that,
<br />"in the event of a power failure or equipment malfunction, storage volume must be greater than or equal
<br />to the average daily consumption, and should include a reasonable fire - fighting reserve." This
<br />requirement may be reduced when the source water and treatment facilities have sufficient standby
<br />power capacity to maintain production during electrical power interruption.
<br />The Insurance Services Organization (ISO) publishes their own storage adequacy guidelines, which
<br />recommend that the storage and distribution system be capable of supplying at least the third highest
<br />Recommended Standards for Water Works, 1997, Great Lakes, Upper Mississippi Board of State Public Health and Environment.
<br />8 -10
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