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Show DEFICIENCIES OF PROJECTS INSUFFICIENT ATTENTION TO THE NEEDS FOR RELIABLE AND ADEQUATE SAMPLING Essential Features of the National Water Resources Basic- Data Program Until recently water has been considered a gift of nature to be accepted for use in the quantities and mainly at the time and places supplied by nature. This has now all been changed, and water has become, aside from land itself, the most valuable and actively managed of our natural resources. We are now embarked on the planning and construction of great diversion works and facilities designed to make water more readily available for its multiude of uses, and to control and reduce its destructive powers. Recent rapid growth in the engineering works designed to in- crease the usefulness of water has brought the volume of public and private expendi- tures for the development and control of this resource to a magnitude far in excess of that for any other resource and, for the Federal Government, even beyond the total of all other resources combined. The use of water for domestic, industrial, irrigation, and other needs has expanded to such a degree that many localities have reached the limit of economic development that can be sustained from existing water supplies. Unfortunately some areas have gone far beyond this limit, especially areas exploiting ground- water resources. Some large metropolitan districts have already embarked on costly projects for importation of water from areas where the demand has not yet reached the limit of available supply, but some communities will find it impossible to augment their supplies and others actually face liquidation of part of their industry and population. Unfortunately, however, these rapidly expanding water resource development projects have not been matched by a corresponding increase in the hydrologic basic- data studies and other scientific investigation required to reveal the full nature of water resources and the maximum quantities that can be made available for beneficial uses. Sporadically, rather than systematically, provisions have been made for expanded hydrologic research, usually only after the general plans and actual designs of structures have progressed through the preliminary and sometimes to an advanced stage. The logic and basic soundness of completing hydrologic studies well in advance of project planning would seem self- evident and overwhelming. DEFICIENCIES IN OUR BASIC DATA PROGRAM IN WATER RESOURCES The inadequacy and fragmentary nature of the present basic- data program may be characterized as follows: ( 1) No satisfactory determination has yet been made of the gross quantities of precipitation in each catchment area or drainage basin. Precipitation is now recorded at a limited number of stations, but these have been located with insufficient attention to the needs for reliable and adequate sampling of precipitation and other climatol- ogical phenomena. The sampling is satisfactory only in areas of even topography but is very inadequate and misleading for mountainous areas where extreme differences in precipitation caused by topographic and other disturbances to moisture- laden air masses occur even over short distances. High elevations, where precipitation is heaviest, generally have very few precipitation stations. This inadequate program of sampling precipitation is especially unfortunate in face of the fact that it is in those same mountainous areas where the water resouce development projects are most costly and most heavily concentrated. 25 |