WSP07805

• File Number: 8270.100
• Description: Colorado River Basin Water Quality/Salinity -- Misc Water Quality
• Basin: Colorado Mainstem
• Water Division: 5
• Date: 2/1/1984
• Title: Colorado River Water Quality Improvement Program - Meeker Dome Unit Colorado - Preliminary Findings Report - Feb 1984
• Water Supply Pro - Doc Type: Report/Study

CHAPTER IV

PROBLEM IDENTIFICATION AND
QUANTIFICATION ACTIVITIES

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flows measured on Coal Creek below Little Beaver Creek from 1978 through
1982 have ranged from 1.5 to 155 cfs and have averaged 20.7 cfs. In the
lower part of the basin, flows are diverted by ditches to irrigate
rangeland on the east and northeast flanks of the dome.

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Curtis Creek enters the White River immediately downstream from the
dome. During the period 1978 through 1982, the gage on Coal Creek
measured flows averaging approximately 0.5 cfs and ranging from 0.02 to
5.8 cfs. The drainage area of Curtis Creek includes the northwest flank
of the dome.

The gage in the town of Meeker, in operation since July 1978, re-
corded an average flow of 608 cf s during the years 1979 through 1982
compared to 535 cfs at the gage upstream from the dome during this same
time period. Thus, 73 cfs were gained from the drainage area between
these gages which included drainage from the dome.

Several additional irrigation diversions affect White River flows
between Coal Creek and Meeker. The increased river flow along this
reach indicates a complex interaction of diversions, irrigation return
flow, interbasin transfers and imports, natural tributary inflow, and
seepage from the dome.

Ground water resources

At least nine artesian aquifers exist in the upper 2,l00 feet of
Meeker Dome, which contained saline water prior to the study. The Weber
Formation and the Entrada Sandstone were believed to be the primary
saline aquifers under the dome. Additionally, there were thought to be
many thin but productive saline aquifers between these two strata and
above the Entrada. Only the Entrada and lower formations were likely to
have contained saline water under sufficient artesian pressure to flow
to the surface at the time the Marland Well was drilled. Drilling the
Marland Well created a direct connection between the lower aquifers and
the upper formations. Through the connection, permeable but previously
unsaturated formations were charged. When formerly distinct aquifer
waters became cross connected, quality in the aquifers became essen-
tially identical. The aquifers in the Morrison and upper formations
were believed to be the primary conduits for the deep saline water from
the oil wells to reach the surface. More is known about these aquifers
than others because of their relatively shallow position.

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Fractures have created a thin but productive and well-confined
aquifer in the upper 120 feet of the Morrison Formation. This aquifer
was believed to be the primary source of the saline springs along the
south-central face of the dome.

Although the transmissivity of the upper water-bearing zone in
the Morrison Formation was not estimated, it appeared to be highly vari-
able and derived primarily from fractures in the hard siltstones and
shales of the aquifer. The geologic structures present on Meeker Dome

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