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Show which all natural water contains in varying amounts, determines whether the water is good, poor, or unsatis- factory for industrial, agricultural, municipal, and other uses. Increasing demands for water meeting exacting quality specifications require the expansion of facilities for collecting and evaluating the water resources of the Nation with reference to chemical quality. The Geologi- cal Survey is currently collecting most of the data on the chemical quality of natural waters. Figure 29 shows the adequacy of chemical water quality information for surface and ground waters in terms of per- centage of adequate coverage. In order to determine the present coverage, each subbasin was considered in the light of current and past records. An estimate was then made of the amount of chemical quality information re- quired for the development and utilization of water re- sources in each subbasin. The percentage of adequacy was computed from the ratio of existing records to the estimated total records required. Chemical water quality studies consist of two distinct phases, (1) determination of basic chemical data on surface water and ground water supplies, in accordance with standard methods of the Geological Survey; (2) the interpretation or evaluation of these basic records with respect to geology and hydrology. The studies include salt water intrusion problems in coastal areas. After determining the present status of information concerning the quality of ground and surface water supplies, appro- priate weighting for surface water coverages, ground water coverage, and interpretation of the records were used in arriving at the present adequacy of chemical water quality information in each subbasin. In the States west of the Mississippi River a survey was made, in 1949, to determine the needs of all Federal agencies for information on the quality of surface waters, primarily in connection with irrigation. The recommen- dations for water quality stations for irrigation, together with allowance for other major uses of water, such as industrial and municipal, were considered in the prepara- tion of figure 6. There are currently about 220 daily water-sampling sta- tions in operation for determination of chemical quality. To overcome the deficiencies in these data, it will be necessary to establish approximately 1,200 additional daily sampling stations (or their equivalent) throughout the country. Daily temperature readings should be taken at these stations. These additional stations should be acti- vated in an orderly manner during the next 10 years. Additional laboratory facilities will also be needed to handle the large number of samples that will result from an expanded program. Sanitary Water Quality Data The Federal Water Pollution Control Act of June 30, 1948, gives the Public Health Service a major responsi- bility for reclaiming and conserving the sanitary quality of our interstate waters. The Public Health Service is directed to prepare or adopt comprehensive programs for abatement and prevention of stream pollution, and to im- prove the sanitary quality of water needed for various uses including: "Public water supplies, propagation of fish and aquatic life, recreational, agricultural, industrial, and other legitimate uses." Comprehensive programs in cooperation with other Federal agencies, State water-pol- lution agencies and interstate agencies, municipalities, and industries are being developed. The first step in this Nation-wide program involved a study of the effect of every sewage and industrial waste discharge on the receiving stream. For each source of pollution, data must be collected on the flow, strength, and character of the pollution and on the physical, chemical, bacteriological, and other biological changes in the stream resulting from pollution. These data are used, together with stream discharges and velocities, precipita- tion, wave action, wind action, ice cover, and other factors which influence the self-purification capacity of the stream. Before stream pollution data may be used, the most desirable downstream water uses must be determined. Such water uses will govern the amount of pollution that may be tolerated. In this connection, it should be stated that there are no generally accepted quantitative bac- teriological standards for many important water uses, including irrigation and bathing. Research in these water uses is now being conducted to relate bacteriological concentrations in the water to disease incidence. The situation is even less satisfactory at present with respect to industrial pollutants. Such wastes may not only make the water unfit for human use, but may also be toxic to fish or to the microscopic organisms that serve as food for fish. Research to determine allowable limits for such pollutants has been undertaken by Federal and State agencies and by various universities. Until maximum tolerable values are known, the fitness of a water for a given use must be based to a large extent on direct observations of pollution and on experience and judgment. Since 1939 the Public Health Service has maintained an up-to-date inventory of sewage facilities which covers 22,500 communities in the Nation, including 9,000 served by sewer systems. The data comprising the inventory are furnished annually by the sanitary engineering divi- sions of the State departments of health. A supple- mentary arrangement was completed in 1949 whereby the States undertook to furnish additional information, in- cluding annual data, on: Flow and character of wastes, treatment applied, downstream water uses, effect of pollu- tion on these uses, and corrective measures required. Determinations of sewage strength are routinely per- formed by most State health departments or by treatment plant laboratories under their supervision. Data on sewage flow are usually available at larger treatment plants. Flow data at smaller plants may usually be estimated with acceptable accuracy. In respect to sewage data, it is believed that minimum needs in most areas will be satisfied. With the exception of a few States which have stressed industrial waste investigations, the situation with respect to data on industrial wastes can be much improved. The task of determining the flow and character of the industrial wastes will take years at the present rate of progress. Ac- tive cooperation of industry has been enlisted as a prac- tical approach to the problem of securing minimum essential data within a reasonable period of time. Exist- ing resources of the States and the Federal Government are being applied to evaluate many thousands of independ- ent industrial waste discharges. 345 |