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Show Programs for Additional Improvements The Corps of Engineers has contemplated ex- tending navigation to Yankton, by open channel. Investigations have also been made of the feasi- bility of providing navigation on the principal tributaries. Another possibility is slack-water navigation. This alternative would demand smaller amounts of water during low-flow periods and would provide incidental hydroelectric power generation. Municipal and Industrial Water Supply- Over 90 percent of the towns of the Missouri Basin, with a total population of about 3.8 million, are served by public water supplies. Larger cities tend to use surface supplies and smaller communi- ties to use underground water. Less than a sixth of the communities use surface water supplies, but they use 60 percent of all the municipal water con- sumed in the basin. Both surface and ground water supplies are therefore important. Communities in the basin use about a half-billion gallons of water daily, and industries about a billion gallons more. Quality of water varies from excellent to unus- able. Surface waters generally are highly miner- alized and commonly contain large quantities of sediment, though this is much less true at the ex- treme eastern and western edges of the basin. Quality of ground water varies much more than that of surface water. Throughout much of the basin it is very hard. Particularly in the upper basin, where a high percentage of municipalities are dependent on ground water,2 quality is unsat- isfactory. Among the causes of poor quality are presence of carbonates, sulfates, fluorides, high gas content, high temperature, metallic oxides, abra- sives and silt in suppression and unpleasant taste, odor, or color,3 as indicated in table 5. Some are unfit for human use. The quantity of ground water is inadequate in many localities, particularly in the upper basin States. Parts of southern Iowa and northern Mis- souri also are reported to have inadequate supplies. During the <lrought of the 1930's, water supplies * Eighty-five percent of the 495 municipalities with or- ganized waterworks in the upper basin States in 1948 were dependent on ground water (Bureau of Reclamation). * Bureau of Reclamation. declined and in some localities failed completely. Since then they have generally recovered. How- ever, in the upper basin consumption normally is very low in comparison to the United States aver- age. In nearly 60 percent of the municipalities of the upper basin States per capita consumption is less than half the national average. Forty-eight percent of the population in municipalities of the upper basin States is thought to be without suitable and fully adequate public water supplies. Increasing domestic, commercial, and industrial use, lowered ground water levels, decreasing re- charge rates, and expanding requirements for pol- lution abatement are expected to create local prob- lems in the future. Among the municipalities which have, or in the near future are expected to have, water supply problems, are Denver, Colo.; Moorehead, Minn.; Dillon, Mont.; Fargo, Grand Forks, and Jamestown, N. Dak.; Sioux Falls, Rapid City, Aberdeen, Huron, Mitchell, and Belle Fourche, S. Dak.4 Surface water pollution has caused difficulties. They have been a source of real concern in some localities which use surface water for municipal water supply. Pollution is particularly serious during the winter season. Several diversions of water for municipal use are of interest. One is from the Big Hole River in Montana to serve Butte, outside the basin. An- other diversion has been planned to serve 20 or more cities and towns in the Souris-Red River Basins and elsewhere in North Dakota. Colorado River water is being diverted into the basin, and, as noted, Denver gets some of its supply from the tributary Fraser River by way of the Moffat Tunnel. Watershed Management A watershed management program has been under way for many years. This first took the form of setting aside forest reserves (later national for- ests) for the dual purpose of conserving timber and water resources. To the original lands, some 460,000 acres have been added by purchase and exchange, primarily for watershed protection. At present there are some 16,345,000 acres in 19 na- tional forests in Montana, Wyoming, Colorado, South Dakota, Nebraska, and Missouri. * Bureau of Reclamation. 184 |
