7897

• UCREFRP Catalog Number: 7897
• Author: Apodaca, L. E., N. E. Driver, V. C. Stephens and N. E. Spahr.
• Title: Environmental Setting And Implications On Water Quality, Upper Colorado River Basin, Colorado And Utah.
• USFW Year: 1996.
• USFW - Doc Type: Water-Resources Investigations Report 95-4263,
• Copyright Material: NO

Table 5. Generalized water budget for the Upper Colorado River Basin study unit
Inputs
(acre-feet per year) Outputs
(acre-feet per year)
Precipitation 20,980,000 Evapotranspiration from nonirrigated land (residual) 14,91Q000
Surface-water inflow 0 Surface-water outflow 4,491,000
Interbasin water transfers (negligible) 0 Consumptive water use 871,000
Ground-water inflow (negligible) 0 Interbasin water transfers 585,000[
Reservoir evaporation 123,000
Ground-water outflow (negligible) 0
Change in ground-water storage (negligible) 0
Total (rounded) 20,980,000 20,980,000
1 Data from U.S. Geological Survey National Water Information System and Upper Colorado River Commission, 1993
promote efficient runoff; annual precipitation is suii`i-
cient to fully recharge the aquifers in most years,
thereby maintaining base flow year round. Low-
altitude streams are at altitudes below 7,500 fl and
receive less than 20 in. ofprecipitation annually,
mostly from thunderstorms. The basins for low-
altitude streams have flat slopes and thick deposits of
soils and alluvium that attenuate runoff. Annual
precipitation is insufficient to recharge aquifers to
produce a continuous base flow. Mixed-type streams
have headwaters in the mountains or high mesas but
flow through the low-altitude regions.
Three stations have been selected to illustrate the
differing flow characteristics of these stream types
(table 6). The Colorado River below Baker Gulch
(station 09010500, fig. 1) is on ahigh-altitude type
stream having a drainage area of 53.4 mil and a mean
annual streamflow of 62.3 ft3/s. West Salt Creek near
Mack (station 09153400, fig. 1) is on aloes-altitude
type stream and has a drainage area of 168 mil and a
mean annual streamflow of 0.88 ft3/s. This station only
has 10 years of record and, therefore, flow characteris-
tics at this station are not well defined. However, this
record is among the longest for low-altitude streams in
the basin that are not greatly affected by return flows or
interbasin water transfers. The Colorado River near
Cameo (station 09095500, fig. 1) is on a mixed-type
stream and has a drainage area of 8,050 miz and a mean
annual streamflow of 3,870 ft3/s. This station is
affected by interbasin water transfers, storage reser-
voirs,power development, and diversions for irrigation
of about 160,000 acres.
Table 6. Hydrologic characteristics of selected surface-water stations in the Upper Colorado River Basin study unit
[mil, square miles; fry/s, cubic feet per second; in., inches; Q-7-10, 7-day 10-year low flow; ~, approximate]
Station Station Station
09010500 09153400 09095500
Hydrologic characteristic Colorado Rlver WestSeltCreek Colorado River
below Baker
near Mack, near Cameo,
Gulch, Colorado Colorado
Colorado
Period of record (water yeaz) 1954-1993 1974-1983 1934-1993
Drainage azea (miZ) 53.4 168 8,050
Mean annual streamflow (ft3/s)
Coefficient of vaziation of annual mean streamflow
Mean annual runoff (in.)
10-year flood (ft3/s)
Q-7-10 (ft3/s)
62.3 O.RB 3,870
0.33 1.03 0.30
15.8 0.07 6.53
800 140 28,000
3.9 0 1,050
ENVIRONMENTAL SETTING 19