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<br />74
<br />
<br />"It "4,
<br />
<br />HYDROLOGIC AND HUMAN ASPECTS OF THE 1976-77 DROUGHT
<br />
<br />mum levels were reached in March 1977 on
<br />Maui and two in late August or early Septem-
<br />ber 1977 on Oahu. Both basal water tables and
<br />a high elevation aquifer are represented in this
<br />sample. The record on the latter started in
<br />1936, Though water levels were very low, no
<br />significant reductions in water yield occurred.
<br />There was no significant increase in the
<br />number of wells drilled in 1976 or 1977.
<br />
<br />Water Quality
<br />
<br />The chemical quality of surface waters did
<br />not change significantly during the drought.
<br />Dissolved-solids concentration increased
<br />slightly, but sediment concentrations and dis-
<br />charges decreased, The sediment discharge
<br />during the 1977 water year of Waikele Stream
<br />into Pearl Harbor was one-ninth that of the
<br />previous year.
<br />Though flows were less, stream water
<br />temperatures were near seasonal normals.
<br />
<br />Activities Resulting from the Drought
<br />
<br />The below normal runoff produced the most
<br />serious problems in the areas that have no
<br />development of ground-water resources such
<br />as East Maui, The areas that rely on surface-
<br />water supplies and limited water storage facil-
<br />ities were hard pressed to meet the demand.
<br />The Kona area on the island of Hawaii was de-
<br />clared in a state of drought emergency in
<br />January 1977. Water was hauled to families in
<br />the area, lawn watering and car washing were
<br />prohibited, macadamia nut growers were asked
<br />, to reduce the amount of water used for irri-
<br />gation, and cattle ranchers had less water for
<br />their livestock, Similar constraints were
<br />imposed on most of Maui where residents were
<br />asked to reduce their water consumption by 30
<br />percent, and the truck farmers were limited to
<br />two irrigations per week.
<br />The least effect was on Kauai. No state of
<br />emergency was declared, but sugar cane grow-
<br />ers hopeq for rain to supplement the
<br />diminished flows in the irrigation systems,
<br />On Oahu, requests were made to cut water
<br />use by 10 percent for residential use, by 15
<br />percent for commercial and agricultural uscs,
<br />and by 50 percent on parks and golf courses.
<br />Though no drought emergency was declared in
<br />1977, the Honolulu Board of Water Supply pro-
<br />posed rules and regulations to initiate manda-
<br />
<br />tory water conservation measures in the sum-
<br />mer of 1978, if necessary.
<br />
<br />The Eleven Other WRC Regions
<br />
<br />Seven of the other eleven WRC regions
<br />stretch from Maine to California, along the
<br />Atlantic and Gulf coasts, and along the Mexi-
<br />can border. Two are interior regions, the Ohio
<br />and the Tennessee regions, and the other two
<br />regions are Alaska and Puerto Rico,
<br />, There was no or virtually no drought in
<br />tl)ree regions; New England, Region 01; Lower
<br />Mississippi, Region 08; and Alaska, Region 19.'
<br />In six regions, Ohio, Tennessee, Texas-Gulf,
<br />Rio Grande, Lower Colorado, and Caribbean,
<br />respectively Regions 05, 06, 12, 13, 15, and 21,
<br />the effects of the drought were relatively
<br />minor--either in localized areas or for short
<br />durations similar to other dry years. The Mid-
<br />Atlantic, Region 02 and the South Atlantic-
<br />Gulf, Region 03, had more serious drought
<br />problems in small parts of the regions, Brief
<br />descriptions of the conditions in Regions 02
<br />and 03 and a few highlights from the other
<br />Regions are presented in this section,
<br />Previous droughts have been described by
<br />many writers, among them Barksdale and
<br />others (1966), Benson and Gardner (1974),
<br />Gatewood and others (1964), Hoyt (1936,1938),
<br />Nace and Pluhowski (1965), Thomas and others
<br />(1963a-d), and Water Resources Council (1966).
<br />Palmer and Denny (1971) have compiled a
<br />bibliography of other drought reports,
<br />
<br />Precipitation and Runoff
<br />
<br />Four months of deficient rainfall from
<br />April to July 1977 was the primary cause of
<br />drought conditions in South Carolina, Runoff
<br />during the previous winter was near normal,
<br />but the dry period started about 2 months
<br />earlier than usual, thus causing adverse im-
<br />pacts on agriculture, Rain in early August
<br />prevented a severe drought from developing.
<br />Deficient rainfall in Georgia and the longer
<br />than usual intervals between rains, some as
<br />long as 8 weeks, caused farmers to delay their
<br />planting of crops because moisture is needed
<br />to activate the chemicals in pesticides and
<br />weed control agents. Monthly rainfall in April
<br />and May in southwest Georgia usually exceeds
<br />4 in,; but rainfall in April 1977 was only 1.29
<br />in" and during the first 19 days of May it was
<br />only 0,33 in.
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