PUB00013

• Year: 1985
• Title: Estimated Use of Water in Colorado 1985
• CWCB Section: Water Conservation & Drought Planning
• Author: David W. Litke and Cynthia L. Appel
• Description: Water-Resources Investigations Report 88-4101
• Publications - Doc Type: Brochure

Information about water use in the oil industry was obtained from the
Colorado Oil and Gas Conservation Commission. Water produced as a byproduct
of oil production is considered a mining withdrawal. The water is either
turned into evaporation ponds where it is consumptively used, or it is
reinjected. The Oil and Gas Commission keeps records on water production and
water reinjection for each oil field in Colorado. From these records, it was
estimated that 32.25 million gallons per day of saline ground water was
withdrawn in Colorado during 1985, and 6.86 million gallons per day was
consumptively used by evaporation from ponds; the remaining water was
reinjected. An additional 2.84 million gallons per day of surface water was
withdrawn and consumptively used for production injection. Most of the
oil-field water use occurred in Rio Blanco, Washington, Logan, Morgan, and
Moffat Counties.

There are few previous estimates of m1n1ng water use available. The 1982
Census estimate of 65 million gallons per day (U.S. Bureau of the Census,
1985, p. 4-5) includes responses from only 49 of the estimated 2,424 mining
establishments then in the State. The mining industry is notably volatile,
and water use can change dramatically from year to year. It is particularly
difficult in this category to define water use. Mine dewatering is an
important part of mining water use but often is a passive type of use. For
example, some mines are temporarily closed but either are dewatered in
anticipation of re-opening, or have a passively occurring discharge from the
mineworks that mayor may not be processed in a mine-operated treatment plant.
In addition, many old, long-abandoned mines discharge water. This water was
not considered a mining use for this study, and, in any event, would be
difficult to quantify.

The mining industry used an estimated 91.3 million gallons per day of
water in Colorado during 1985. Six percent of this was used by coal mining,
46 percent by hardrock mining, 10 percent by sand and gravel quarrying, and 38
percent by oil production. All of the water was self-supplied, and 23 percent
was consumptive use. The distribution of mining water use by county is
shown in figure 9. In general, those counties that show large use in the
eastern part of the State are oil-production counties, those in the central
part of the State are hardrock-mining counties, and those in the western part
of the state are coal-mining counties. Tabular summaries of mining water-use
data are listed in table 10 (for counties) and table 21 (for hydrologic
subregions) in the "Supplemental Data" section at the back of this report.

Power Water Use

The power water use category includes hydroelectric power water use and
thermoelectric power water use. Thermoelectric power water use is further
subdivided by fuel type (fossil, geothermal, and nuclear). Data were compiled
for the power water use category for water-source type, water-supply method,
water-disposition type, and quantity of power generated.

Data for the power water use category were compiled by making a complete
survey of power plants. The 23 thermoelectric-power plants in Colorado
generated 26,500 gigawatt-hours of net power during 1985, and the 27
hydroelectric-power plants in Colorado generated 2,400 gigawatt-hours of net

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