Studies were made in the National Hydraulic Laboratory to ascertain the position that should be taken by the engineer in making discharge measurements by wading, in order to avoid or minimize the possibility of affecting the velocity of the water passing the current meter. Similar investigations were made at gaging stations on several rivers in New Jersey as an extension of the laboratory studies to field conditions. These research investigations will lead to improvements in methods of field work, with a resulting increase. in accuracy and efficiency of operation.

Division of Ground Water.-The Division of Ground Water investigates the waters that lie below the surface in the zone of saturation, from which wells and springs are supplied; the source, occurrence, quantity, and head of these waters; their conservation; their availability and adequacy for domestic, industrial, irrigation, and public supplies and as watering places for livestock and desert travelers; and the methods of constructing wells and recovering water from them and of improving springs. The constantly increasing use of water supplies from wells is causing a greater demand each year for intensive studies of the quantities of ground water that are perennially available.

During the year about 85 technical reports or papers relating to ground water were released to the public, and 28 technical papers were presented by members of the Division before scientific societies or other organizations.

Periodic measurements of water levels or artesian pressure were made in about 5,500 observation wells, on about 265 of which recording gages were maintained. The report on water levels and artesian pressure in observation wells in the calendar year 1938 was published as Water-Supply Paper 845, and a similar report for 1939 is in press as Water-Supply Paper 886. Tests on 44 water-bearing materials were made in the hydrologic laboratory.

Work was done in 38 States and in Hawaii and the District of Columbia, nearly all in cooperation with Federal, State, Territorial, or local governmental agencies.

WORK OF THE YEAR, BY STATES

In Alabama an investigation of ground water was begun in the Cretaceous area of the Coastal Plain. In Arizona investigations were begun, chiefly in the Gila River Basin. A report on ground-water recharge from floodwaters of Queen Creek was released to the United States Army engineers. In Arkansas studies were continued in the Grand Prairie region, and a report was made to the State geologist on the water-well survey of the Work Projects Administration. In California an investigation was begun in the coastal area of Orange and Los Angeles Counties, and water levels were measured in observa

tion wells in several areas. A report on the geology and ground-water hydrology of the Mokelumne area, California, was published as Water-Supply Paper 780. In Colorado investigations and reports were made on prospective well sites on the public lands in the western part of the State. In Connecticut work was continued on water levels in observation wells, and reports were prepared on the New Haven area and on the area in the vicinity of the Federal Correctional Institution at Danbury. In the District of Columbia a survey was made of ground-water pumpage, and periodic measurements were started on several observation wells. In Florida investigations were continued in the Jacksonville area; work was started in the Miami and Pensacola areas; and a summary on ground-water resources of the Pensacola area was released. In Georgia investigations were continued in the Savannah area and other parts of the Coastal Plain, and a report was released on the artesian water in the coastal area. In Hawaii work was continued on several of the islands; the geophysical phases of the studies were completed; and several papers on ground water were released.

In Idaho periodic measurements of water levels were made in several observation wells. In Indiana work was continued in the Indianapolis area and on the State-wide observation-well program. In Iowa work was continued on Statewide ground-water studies and on a study of the effects of soil conservation on ground-water levels in the Tarkio Basin. In Kansas work was continued in the Wichita and other areas; a large program of new work was started in the western part of the State; and several papers relating to ground water were released. In Louisiana investigations were continued, chiefly in Grant, LaSalle, Acadia, and Jefferson Davis Parishes. Several papers on ground water were released, and a report on the ground-water resources of Rapides Parish was published by the State Geological Survey as Bulletin 17. In Maryland periodic measurements were made of water levels in several observation wells. In Massachusetts work was continued on a small scale on ground-water studies and measurements of observation wells. In Michigan work was continued on the observation-well program. In Mississippi work was continued in the alluvial plain of the Mississippi Valley and in the coastal area. In Missouri water levels were measured in several wells in the Tarkio Basin. In Montana the observationwell program was continued on the lowlands at the head of Flathead Lake. In Nebraska work was continued on State-wide investigations, and several reports were released. In Nevada a brief investigation and a report were made on the Ruby Valley. In New Jersey observations and studies were continued in several areas. In New Mexico studies were continued in the principal ground-water areas, and 6 reports were published by the State Engineer. In New York observations and studies were continued on Long Island. In North Carolina a study of methods of developing wells was continued at Elizabeth City, also the program of water-level measurements in wells in different parts of the State. In North Dakota the observation-well program was continued, and work was begun in the Fargo and other areas. In Ohio work was continued in Hamilton and Butler Counties, in the Cincinnati area, and a report on the area was released. In Oklahoma work was continued, chiefly in the Panhandle, and several reports were released. The report on the geology and ground-water resources of Texas County was published by the State Geological Survey as Bulletin 59. In Oregon work was continued in different areas, and several reports were released to the United States Army engineers. A report on the geology and ground-water resources of the Harney Basin was published as Water-Supply Paper 841.

In Pennsylvania the observation-well program was continued, and a report on ground water in north-central Pennsylvania was published by the State Topographic and Geologic Survey as Bulletin W 6. In South Carolina studies were continued on the ground-water levels in the Tiger River area. In South Dakota work was begun on a program of observation wells. In Tennessee records were obtained of the current pumpage and water levels in observation wells in Memphis. In Texas work was continued in many areas, new work was begun in the Pecos River Basin, and a number of ground-water reports were released. Records of wells and springs in 20 counties were mimeographed by the Work Projects Administration. In Utah a State-wide observation-well program and studies in the Cedar City area were continued, and several reports were released. A report on artesian water levels and interference between artesian wells in the vicinity of Lehi was published as Water-Supply Paper 836-C. In the Virgin Islands a report was in preparation on the Island of St. Croix. In Virginia work was continued in the southern part of the Coastal Plain. In Washington studies were continued on a State-wide program and in the Tacoma and Bremerton areas. In Wisconsin records were obtained of water levels in several observation wells.

Division of Quality of Water.-The Division of Quality of Water analyzes water from surface and underground sources with reference to its suitability for industrial and agricultural uses and for domestic use (not related to questions of health) so far as such use is affected by the dissolved mineral matter. During the year, analyses were made in Washington of 2,255 samples of water from surface and underground sources. The analyses included many made for cooperative studies of ground water in the different States and for special investigations of water supplies for specific projects. During the year, 10,921 samples were examined by or under the technical supervision of the Division of Quality of Water in field laboratories at Miami, Fla., Roswell, N. Mex. (substation at Albuquerque), and Austin and Pecos, Tex. At Boise, Idaho, the silt content was determined for 32,471 samples from the Boise River and its tributaries. The silt content of 7,850 samples from streams in or near projects of the Soil Conservation Service of the Department of Agriculture was determined in field laboratories at Shenandoah, Iowa (Tarkio, Mo., project), High Point, N. C., Pullman, Wash., and LaCrosse, Wis.

Studies of suspended and dissolved matter of the Colorado River and its tributaries were continued. Tables of analytical data for Colorado River gaging stations at which samples were collected through the water year 1938-39 (Grand Canyon and Willow Beach gaging stations for part of the 1940 water year) were filed with the Survey offices at Denver, Colo., Los Angeles, Calif., Salt Lake City, Utah, San Francisco, Calif., and Tucson, Ariz. Tabulations of analyses of samples from different depths at several points in Lake Mead were furnished to the Bureau of Reclamation. An intensive study of the chemical character of the water of the Pecos River in New Mexico, which was begun in cooperation with the State Engineer

of New Mexico in 1937, was continued as a part of the joint investigation of the Pecos River Basin under the auspices of the National Resources Planning Committee and was extended to cover the part of the river basin in Texas. Field studies were made of the sources of saline water in the basin. Analyses of composites of daily samples of surface water and analyses of single samples of surface water and of ground water were tabulated and made currently available at the laboratories in Roswell, N. Mex., and Pecos, Tex., where the analyses were made.

Tables of records of precipitation, discharge, and suspended matter at gaging stations on four demonstration projects of the Soil Conservation Service, Department of Agriculture, for the year ending September 30, 1939, were released to the Soil Conservation Service. Studies of silt movement in streams in the Boise River Basin in Idaho and in the St. Francis River Basin in Missouri were made for the Flood Control Coordinating Committee of the Department of Agriculture, and preliminary reports on the measurements of discharge and suspended matter were released for the period January through September 1939 for the Boise River Basin and for the period February through September 1939 for the St. Francis River Basin.

Close cooperation was continued with the Division of Ground Water in the study of problems relating to quality of ground water and in the preparation of the parts of ground-water reports that involve consideration of the chemical character of the waters. Miscellaneous water analyses were made for the Department of Agriculture, the Department of Commerce, the Navy Department, and the Securities and Exchange Commission. The division furnished information and advice on problems relating to quality of water to the Biological Survey, the Bureau of Reclamation, and the National Park Service, of the Department of Interior; also to the Bureau of Foreign and Domestic Commerce, the Bureau of Plant Industry, the Federal Housing Administration, the Federal Trade Commission, the Food and Drug Administration, the National Bureau of Standards, the National Institute of Health, the National Resources Planning Board, the Navy Department, the Netherlands Legation, the Public Health Service, the Public Works Administration, the Reconstruction Finance Corporation, Office of the Chief of Engineers, the United States Travel Bureau, the National Geographic Society, and to numerous companies and individuals. Twelve technical papers relating to quality of waters were prepared for publication in journals or for presentation before scientific societies or other organizations.

Division of Water Utilization.-The Division of Water Utilization conducts hydrologic studies and compiles data relating to the utilization and control of the waters of streams. It supervises

studies of hydrologic problems made by the field personnel of the branch and serves in an advisory capacity in the administration and conduct of various water-resources investigations and related governmental activities.

The collection of stage and discharge data relating to outstanding floods and miscellaneous studies of water resources in several of the district offices of the branch were supervised and coordinated, and the work of assembling data and general information on floods was continued. Projects involving compilations of information on topographic characteristics of drainage basins that may relate to deternination of flood flows were supervised. The initiation and conduct of some of these projects were sponsored by the Public Works Administration and the Work Projects Administration. Studies were made of the surface-water hydrology of the demonstration projects of the Soil Conservation Service, Department of Agriculture, in connection with the work in which the Survey has been cooperating for several years.

Methods of analyzing relationships between rainfall and run-off with a view to developing a standard method of analysis were studied in collaboration with the Office of the Chief of Engineers of the War Department and several bureaus of the Department of Agriculture. Investigations of the water problems along the international boundary between the United States and Canada have been continued for the State Department and the International Joint Commission. Numerous papers and discussions on hydrologic and hydraulic subjects were contributed to technical and scientific journals.

The following Water-Supply Papers were prepared for publication during the year, and other reports are in various stages of preparation:

843. Floods of December 1937 in northern California, by H. D. McGlashan and R. C. Briggs.

844. The floods of March 1938 in southern California, by F. C. Ebert and H. C. Troxell.

846. Natural water loss in selected drainage basins, by G. R. Williams and others.

847. Maximum discharges at stream-measurement stations through December 31, 1937, by Gordon Williams and Lawrence Crawford, with a supplement including additions and changes through September 30, 1938, by W. S. Eisenlohr, Jr.

867. Hurricane floods of September 1938, by C. G. Paulsen and others.

Division of Power Resources.-The Division of Power Resources collects and compiles information on developed and potential water power of the United States. Information on water-power developments is obtained through the cooperation of the field engineers of the Division of Surface Water and the Federal Power Commission.

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