WSP02495

• File Number: 5970
• Description: Flood Protection Section - Miscellaneous Reports
• State: CO
• Basin: Statewide
• Date: 3/1/1981
• Author: USGS
• Title: Water Resources Investigations of the US Geological Survey in Colorado - Fiscal Year 1981 - Open-File Report 81-150
• Water Supply Pro - Doc Type: Report/Study

001558

In addition to the water-quality data collected at the stations, a variety of
water-qual ity data also are collected at numerous sites during the course of many
interpretive hydrologic studies. These data are available from the files of the
U.S. Geological Survey.

Ground-Water Data

Water levels in wells are a key parameter for monitoring ground-water trends;
however, they must be integrated with other observations and ground-water investi-
gations in order to have the ful lest meaning and usefulness. A network of 55 ob-
servation wel Is (pl. 1) is maintained in Colorado by the U.S. Geological Survey.
In addition, a network of about 1,151 observation wells is maintained in Colorado
in cooperation with the Colorado Department of Natural Resources, Division of
Water Resources, Office of the State Engineer, for monitoring fluctuations in
water levels. Other wells known as "project wells" are used for specific (gener-
ally short-term) investigations and, although they are not part of the observa-
tion-well networks, data obtained from them also are available. The numbers of
wells currently being measured are given below.

Frequency of measurement

Continuous-----------------------------------------
Monthly--------------------------------------------
Bimonthly------------------------------------------
Semiannually---------------------------------------
Annually-------------------------------------------
lntermittently-------------------------------------

Nwnber of weUs

40
100
52
273
2,193
600

Total-----------------------------------------

3,258

The numbers of wells located in each county are shown in table 1 (p. 8, 9).

Water-quality data are not collected routinely from wells in the statewide
networks. However, a variety of water-qual ity data are collected at numerous
wells during the course of many interpretive hydrologic investigations, which may
include water-quality data from some statewide observation wells. These data are
available from the files of the U.S. Geological Survey.

INTERPRETIVE HYDROLOGIC INVESTIGATIONS

Sixty-seven interpretive hydrologic investigations are being conducted during
fiscal year 1981. These include 12 statewide investigations, 6 regional investi-
gations, 9 investigations in the Missouri River basin, 8 investigations in the Ar-
kansas River basin, 6 investigations in the Rio Grande basin, 21 investigations in
the Colorado River basin, and 5 multi state investigations. The summaries of each
of the investigations that follow consist of a map showing the location of the
area of the investigation and a brief description of the investigation's purpose,
objective, approach, progress, and plans.

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