WSP07449

• File Number: 8056
• Description: Drought Preparedness
• State: CO
• Basin: Statewide
• Date: 7/1/1985
• Author: Resource Consultants
• Title: Droughts and Their Effect on the Water Supplies for the City of Fort Collins Colorado
• Water Supply Pro - Doc Type: Report/Study

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assumed conditions in 1995, and two scenarios were with assumed conditions

in 2035. These five scenarios were selected to provide meaningful compari-

sons between both demand levels and different supply sources.

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The average annual demand for treated water in Fort Collins is presently

around 19,000 ac-ft per year. Model simulations showed that the safe

average demands that could be met with the City's existing water supply,

with no new water added, ranged from 32,400 ac-ft for the l-in-20 drought

to 22,200 ac-ft for the \-in-500 drought. It was concluded that the

existing water supply is capable of withstanding extreme droughts, and with

the current acquisition policy of requiring developers to provide water,

will probably be adequate until the turn of the century.

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Three basic concepts were identified in developing a long-term water

supply strategy for the City of Fort Collins:

1.

Drought design criteria should be established for use in sizing
the water supply system.

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2.

Long-range plans should be developed to meet increased demands

for water while maintaining an adequate safety margin for most

droughts.

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3.

Emergency plans should be developed that can be implemented in

the event of very extreme droughts or failures to water system

components.

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The overriding conclusion resulting from the drought study is that the

City's water supply network is sufficiently sized to withstand relatively

severe droughts and should remain that.way for several years. When severe

droughts do occur, the critical year or years normally occur toward the end

of the dry period. With the existing supply system and with present

acquisition policies, the development of emergency plans is not urgent;

however, it would be desirable to undertake them in the near future.

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Recommendations resulting from the study are as follows:

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1. Fort Collins should determine its optimum drought design criteria

based on an economic evaluation and other factors. A preliminary

conclusion is that the Fort Collins water supply should be

maintained to meet the demands for a l-in-lOO drought.

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