WSP08775

• File Number: 8056
• Description: Drought Preparedness
• State: CO
• Basin: Statewide
• Date: 1/1/1979
• Author: USGS
• Title: Hydrologic and Human aspects of the 1976-77 Drought
• Water Supply Pro - Doc Type: Report/Study

36

HYDROLOGIC AND HUMAN ASPECTS OF THE 1976-77 DROUGHT

wells and pivot-irrigation systems were in-
stalled, and the use of ground water increased.
In 16 counties east of the Missouri River the
irrigated acreage increased 37 percent. In
Beadle County, near Huron, 87 new wells in
1977 represented an increase of 78 percent
over the number operating in 1976. The deep
artesian aquifers were not affected by the
drought, but record low water levels for
periods of up to 25 years were recorded in 86
of 128 observation wells in the glacial drift in
eastern South Dakota late in 1976 or early in
1977. Record low water levels for the last 14
years occurred in 18 of 19 wells in the
alluvium of the Big Sioux River valley in the
southeast corner of the State during the winter
of 1976-77.

Water Quality

On June 21, 1977, a highly toxic concentra-
tion of bluegreen algae was found in the Gray-
ling Arm of Hebgen Lake on the Madison River
just west of Yellowstone National Park. The
deaths of 7 dogs and 27 cattle were reported,
but no ill effects were reported by humans.
The algae bloom was apparently caused by the
low local inflow into the Grayling Arm which
resulted in a rise in water temperature of the
shallow water and by some inflow from the
Madison River which has a higher nutrient
load. The toxic condition disappeared natu-
rally by August 1, 1977. Minor algae blooms
were reported in Ennis Lake downstream from
Hebgen Lake in late August and early Septem-
ber 1977.
Outflows from several reservoirs in Mon-
tana, including Fresno Reservoir, were reduced
in August 1977 to eliminate potential water-
quality problems during the winter by storing
as much water as possible. A shallow lake that
is frozen may develop low levels of dissolved
oxygen because of the uptake by sediments,
and hydrogen sulfide problems and fish kills
may ensue. Also, if lake levels are not high
enough, spawning areas may be exposed and
the fish population will decrease.
Changes in water quality in aquifers were
not observed; however, the sampling programs
are not extensive.

Activities Resulting from the Drought

At Mitchell, S.D., about 50 mi south of
Huron, water was pumped from the James

River into the city reservoirs in April 1977,
Aberdeen north of Huron, and Sioux Falls
restricted water use, and Huron officials
started plans for a well field to supplement
their supply which is obtained from the James
River at a diversion dam upstream. Diversions
for nonmunicipal uses from the James River
upstream from Huron were curtailed in May
1977 in an effort to preserve municipal sup-
plies, and Mitchell initiated water restrictions.
Great Falls, Mont., began water rationing
on July 7, 1977; the 10 percent reduction was
mandatory. Red Lodge, southwest of Billings,
Mont., followed suit in mid-July.
A lightning strike in tinder dry grassland
and timber east of Billings burned 2,300 acres
in July 1977. Besause of the drought and
temperatures of 90 to 1000F the fire danger
remained high for most of the summer.
Seventy-seven counties in three States
were designated as disaster areas because of
the drought.

Missouri Basin-WRC Region 10
(lower part)

The lower part of the Missouri Basin (fig.
14) includes the State of Nebraska, the north-
east quarter of Colorado, the northern half of
Kansas, most of western and northern Mis-
souri, the western quarter of Iowa, and the
southwest corner of Minnesota.
The 1976-77 drought in this region is sum-
marized as follows:
The drought was at its worst in Kansas and
Nebraska in 1976, but 1977 was the worst year
in Colorado and Missouri. Runoff of a number
of streams with long-term records reached
record low values, and storage in most reser-
voirs was below normal.
Many new wells were drilled, ground-water
levels declined, and ground-water mining was
accelerated in western Kansas, but no major
water-quality problems arose either in the
aquifers or in the streams.
Water restrictions were implemented in a
few areas, and weather modification was tried
because of the increased demand for irrigation
water.
Overall the drought was not as severe as
those in the 1930's and 1950's, but it was bad
enough to affect the lives of both rural and
urban citizens.