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<br />78
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<br />. . ''''fl'
<br />
<br />HYDROLOGIC AND HUMAN ASPECTS OF THE 1976-77 DROUGHT
<br />
<br />Basin Commission, 1977) that there is a ten-
<br />dency toward a higher risk of drought in the
<br />1990's than in the 1980's, but a drought may
<br />come in the 1980's, A number of facts, ideas,
<br />plans, programs, and intentions for the future
<br />have been accumulated, discussed, and pro-
<br />posed because of the drought of 1976-77, and
<br />some of these are presented below. Man
<br />usually learns something from his experiences,
<br />though the. transfer of his new knowledge to a
<br />workable solution or the mitigation of a
<br />problem is easier said than done,
<br />Benjamin Franklin once said, "Some people
<br />are weatherwise but most are otherwise,"
<br />Since his time, more and more people have
<br />become weatherwise or at least concerned
<br />about the weather because the weather does
<br />affect the quality of their lives and their eco-
<br />nomic well being,
<br />Probably the most generally recognized
<br />fact that was reemphasized by the drought is
<br />that water is both a limited and a renewable
<br />resource, This apparent dichotomy is mainly a
<br />matter of degree, but it is also related to
<br />changes in other factors in both time and
<br />space. Water may be limited by the short
<br />supply as evidenced by the small amounts of
<br />storage left in many reservoirs by the fall of
<br />1977, Water in a few reservoirs was near the
<br />normal amount, and water in aquifers was still
<br />ample for the current needs, but it was limited
<br />because the means to deliver the water did not
<br />exist, or the cost to pump water from greater
<br />depths was excessive, or as in California
<br />enough baseload power needed to pump ground
<br />water or water in canals, was not available
<br />during the .seasons of high demand, The rains
<br />and snow that came late in 1977 did renew the
<br />supply in reservoirs and brought some ground-
<br />water levels up. However, the aquifers where
<br />subsidence occurred will never be able to con-
<br />tain as much water as they did before the
<br />subsidence because the compaction of the
<br />materials in the aquifer has eliminated a sig-
<br />nificant amount of the pore space. In several
<br />areas the withdrawal of ground water exceeds
<br />the recharge; therefore, the water replenished
<br />just prolongs the time until other serious
<br />problems may develop,
<br />Any plans for the future will not be very
<br />sound unless they are founded on a good data
<br />base and competent analyses and interpreta-
<br />tions of the information, The quantity and
<br />quality of surface and ground waters as they
<br />
<br />occur from day to day must be determined in
<br />sufficient detail so that probabilities of occur-
<br />rence of rare events and the risk involved may
<br />be estimated with more reliability. Also,
<br />because water data are collected only at
<br />selected sites, regional relations need im-
<br />provement so that the data base can be extra-
<br />polated to any point of interest more reliably
<br />than at present. This is particularly true of
<br />low streamflows, Discharge measurements of
<br />low flows are made by the Geological Survey
<br />at gaging stations and numerous miscellaneous
<br />sites where a project is proposed to improve
<br />regional low-flow relations, There are many
<br />areas of the United States where little is
<br />known about ground-water conditions or where
<br />only reconnaissance level studies have been
<br />made, The growing population in arid and
<br />semi-arid areas has increased the demands for
<br />water in parts of the nation where develop-
<br />ment was not foreseen a few years ago and
<br />consequently increased the need for more
<br />water data.
<br />Another important need for future planning
<br />is a better determination of water use, This is
<br />especially true in time of drought, and it is
<br />also important in long-term planning for future
<br />droughts. Efforts along this line have been
<br />made in the past (MacKichan, 1951; Murray
<br />and Reeves, 1977), and a new program has
<br />been started by the Geological Survey in
<br />cooperation with the States to obtain current
<br />data on water use. The National Research
<br />Council has proposed a study on planning,
<br />preparedness, and management in relation to
<br />droughts, and the role of water use data is a
<br />prominent part of the study, The quantifica-
<br />tion of water use will be the basis for analyses
<br />of trends and changing patterns in water use
<br />that in turn will improve plans for develop-
<br />ment of water resources,
<br />Johnston (1978) presented another view-
<br />point on water use when he stated:
<br />
<br />If per capita water usage in an area can
<br />be permanently cut by one-third through
<br />conservation and reclamation, then
<br />developers would have a powerful argu-
<br />ment to justify more growth. More
<br />development, however, would cause
<br />other problems such as traffic conges-
<br />tion, smog, less open space and in-
<br />creased demands for tax-financed ser-
<br />vices such as schools, police and fire
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