Sterling 1996 WC Plan

• Project Type: Water Conservation Plan
• Project Name: City of Sterling Water Conservation Plan
• Title: Water Conservation Plan
• Date: 6/21/1996
• County: Logan
• Water Conservation - Doc Type: Complete Plan

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STERLING WATER CONSERVATION PLAN

MAY 28, 1996

assuming per capita water use stays at the average level of 289 gped. The City's
current capacity is 10.7 mgd. Therefore, the City would still have an average excess
production capacity of 5.3 mgd to handle the projected growth and addition of the
prison.

However, the City is currently planning to add a new well (Well No. 30) in 1996 with an
estimated production capacity of 1,000 gpm. The addition of this new well would
increase the production capacity to 12.2 mgd or 226 percent of the projected average
total daily water demand.

Projected Peak Day Demand

As shown in Table 8, Sterling's maximum day ratio is 2.5. The maximum day ratio (2.5)
multiplied by the projected average daily annual use (5.3 mgd) gives the projected
peak or maximum day use of 13.3 mgd. The projected peak day use would be 26
percent greater than the City's capacity (10.7 mgd). Therefore, the City would need 2.6
mgd of storage to meet the projected peak day use. At this time, the City has 10 million
gallons of storage in four storage tanks.

The addition of well no. 30 would increase the production capacity to 12.2 mgd or 92
percent of the projected peak day demand. Therefore, the City would need 1.1 million
gallons of storage to meet the projected peak day use. As mentioned earlier, the City
has 10 million gallons of storage in four storage tanks.

Projected Peak Hourly Demand

An estimation can be made for the projected maximum hourly demand. The maximum
hourly demand can be estimated by multiplying per capita water use (gped) by 2.5 and
then dividing by 24 hours. Therefore, the projected maximum hourly demand would be
554,000 gallons per hour. This would require 9,236 gpm production for 60 minutes, if
no water storage was used. At this time, the City's maximum domestic water
production capacity is 7,460 gpm or 81 percent of the projected maximum hourly
demand.

The addition of well no. 30 would increase the production capacity to 8,460 gpm or 92
percent of the projected maximum hourly demand. Therefore, the City would need
46,600 gallons of storage to meet the projected peak hourly use. As mentioned earlier,
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Projected Fire Demand

In estimating the water requirements for fire fighting on a population basis, the
American Insurance Association has recommended the following formula:

Q= lOZo.JP(1-0.0l,JP) gpm

For a projected population of 17,000, approximately 4,000 gpm is required for fire
fighting purposes. The Insurance Services Office also suggests that 4,000 gpm should
be maintained for a duration of four hours. Therefore, the peak hourly demand of
9,236 gpm plus the fire demand of 4,000 gpm would total 13,236 gpm. At this time, the
City's maximum domestic water production capacity is 7,460 gpm or 56 percent of the
projected maximum hourly plus fire fighting demand.

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