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

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CHRONOLOGY OF THE 1976-77 DROUGHT

23

Enders Reservoir was 52,840 acre-ft for the
period 1941-67. By 1967 there were only 450
wells in the two counties upstream from
Enders Reservoir, but by 1976 there were
1,&40. The major causes for the increased
number of wells and increased ground-water
withdrawals were below normal rainfall in
1968-70 and the greater number of center-
pivOt sprinkler systems. The connection be-
tween ground-water withdrawals and stream-
flow has been substantiated by single and
double mass curve analyses of monthly flows
(Lappala, 1978). Ground-water levels have
been dropping at a rate closely corresponding
to the increase in the number of wells, and the
flow at the Imperial gage has decreased to
29,920 and 25,310 acre-ft in 1976 and 1977
respectively. The latter flow is only 48
percent of the 1941-67 average and provided
only half the water that was used for irrigation
during the 1960's. Without legislation to
control ground-water use, those using surface
supplies are on a collision course with those
using ground water. Lengthy and costly suits
may be imminent.
To use weather modification or not to use
weather modification is a knotty problem
legally as well as technically. Nebraska 's
statutes assert a "sovereign right" to the mois-
ture in the atmosphere over the State. There-
fore, any unilateral decision to use weather
modification in nearby States is of concern to
Nebraskans. They desire to cooperate in the
decision process so that optimum benefits may
accrue to Nebraska. However, cloud seeding
operations that have been conducted in several
areas of Colorado in previous years were
expanded to other areas in 1977. But fewer
storms and the paucity of the right conditions
for seeding made results inconclusive.
The State of Washington started a weather
modification project on February 28, 1977, and
several public utilities continued their pro-
grams. The State of Idaho threatened to sue
the State of Washington if Washington seeded
clouds that might carry moisture to Idaho. By
late April 1977, the results of the weather
modification activities could not be deter-
mined though some success was claimed for
increasing the snow pack in the Cascades.
The increased use of weather modification
has resulted in laws in some States that
require the contractor to have a license and to
meet specified standards. Other States are

considering what steps they believe are neces-
sary.
Congress passed The Emergency Drought
Act of 1977 which allowed the Bureau of
Reclamation to defer annual operation, main-
tenance, and construction costs up to 5 years
in lieu of other expenses incurred by irrigation
districts.
The large number of requests for permits
for new wells or additional irrigation water
from surface sources created problems with
the existing processing procedures. LegiSla-
tion was enacted, in Iowa, for example, to
streamline the processing so that the Govern-
ment would be more responsive to the needs of
the public. In a drought emergency, time is an
important factor.
The increased use of ground water in
Minnesota caused interference problems be-
tween wells. Legislation was passed in 1977
that requires anyone requesting a permit for a
well to provide detailed hydrologic information
before a permit will be issued. The required
information is not available for all proposed
well sites.

CHRONOLOGY OF THE 1976-77 DROUGHT

The drought that occurred in many parts of
the United States during 1976 and 1977 gen-
. erally was not recognized as being so serious
until well into 1977. Americans seemed opti-
mistic that ample precipitation would fall; and
if not, they had confidence that the dams,
canals, and distribution systems they had paid
for during the last 70 years would tide them
over any "dry spell."
Americans did survive, but not without
some stresses, strains, and economic losses.
Even so, there were individuals and companies
that profited from the drought because they
were in the right place with the right products
or services needed to ameliorate the effects of
the drought.
A number of areas had below normal pre-
cipitation prior to 1976. The western part of
Iowa, eastern South Dakota, and most of
Nebraska had some drought effects as early as
1974, and precipitation during 1975 was below
average in many areas of the country (Environ-
mental Data Service, 1976). Except in the
areas with nonirrigated agriculture, people
generally did not consider the below normal
precipitation to be a serious problem because