WSP06318

• File Number: 8045
• Description: Section D General Studies - Federal Projects - General
• State: CO
• Basin: Statewide
• Date: 12/1/1981
• Author: DOI-BOR
• Title: Front Range Unit - Coal Creek Water Studies - Colorado - Concluding Report
• Water Supply Pro - Doc Type: Report/Study

(J0124~

CHAPTER III--PROBLEMS AND OPPORTUNITIES
WATER SUPPLY

Water supply problems in the Coal Creek area result from a rapidly
expanding population's demands on a limited natural resource, and
urbani zation of the agri cultural communi ty. Thi s competi ti on between
agriculture and urbanization places an increasing demand on the
available water supply.

Coal Creek Basin 1 ies between the Denver metro area and the city of
Boulder. Water supplies for the basin are marginally adequate for the
present service area of approximately 3,840 acres and an estimated 1980
population of 16,040. The expected population by year 2010 is 49,200
with a service area of 30,850 acres. Population projections, which are
shown in table 3, were developed in cooperation with the Boulder County
Pl anni ng Department. The future water requi rements a re based on an
average 180 gallons per capita per day, which is approximately
gO percent of the past usage.

Table 3.--projected population and municipal and industrial
water requirements, Coal Creek study area

Treated water
requi rements
Year Popul ation (acre-feet)
1975 12,155 2,454
1980 16,040 3,550
1990 28,500 5,748
2000 41,900 8,451
2010 49,200 9,924
2020 56 ,400 11,376

The study area's present and future need is for an adequate municipal
water supply. Adequate surface water exists in South Boulder, Boulder,
and Coal Creeks; however, it is virtually all appropriated. At the
present time, over 80 percent of these appropriated supplies are used
for irrigated agriculture.

Water supply storage of approximately 11,000 acre-feet woul d be needed
by the four communities of Superior, Louisville, Lafayette, and Erie to
meet late summer and winter use, and carryover from high runoff years to
suppl ement below average runoff years. The communiti es of Loui svill e,
. Lafayette, and Erie are purchasing irrigation water rights, as avail-
able, for conversion to municipal and industrial use. The water supply
systems of each of the communities are already at a critical stage.
They are marginal for the existing populations, but are totally

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