This report presents the results of water sampling from three lakes in Dakota County over an eighteen-month period. The author determined that "the lakes were shallow, non-stratified, and nutrient-enriched." It includes tables and other figures.

Base from Geologic Map of Pennsylvania, 1980, Pennsylvania Department of Environmental Resources, Bureau of Topographic and Geologic Survey, 4th Series, Map 1.

This report describes "a method for estimating flow characteristics of flood hydrographs between Portland, Colorado, and John Martin Reservoir." It contains maps, graphs, and tables.

From introduction: "The U.S. Geological Survey began a 5-year study of the High Plains regional aquifer during the 1978 to provide the hydrologic information needed for the development of computer models to evaluate the aquifer's response to ground-water management alternatives." It contains maps, graphs, and tables.

This report describes "the ground water hydrology of the Dade County area" and evaluates "the effects of relatively large ground-water withdraws on the local ground-water regimen." It includes maps, sketches, graphs, and other figures.

This report presents findings on "ground-water well inventory, water level measurements, and water-quality samplings" taken in Geauga County, Ohio. It includes maps showing potentiometric-surface changes.

From purpose and scope: This map report represents the first published product of the Loxahatchee River estuary assessment, and primarily fulfills the first objective as outlined above. It presents an overview of the major physical features of the basin and presents selected information on the U.S. Geological Survey assessment.

From introduction: This study was designed to make optimal use of existing data in a short period of time to fulfill an immediate need of the U.S. Forest Service for use in legislatively mandated wilderness-area planning.

From introduction: The purpose of the investigation was to identify and describe the hydrologic units and to evaluate the availability and chemical quality of groundwater in the 1,100 square mile study area.

From abstract: "A series of equations was developed to provide a better method of determining flood frequencies in the Portland-Vancouver urban area that is now available. The resulting regression equations can be used to compute peak discharge and storm runoff with a standard error of estimate of approximately thirty percent." This report contains captioned, black-and-white photographs and a colored map.

This report determines the possible effects of constructing an interstate highway on the nearby Rogers Lake in Dakota County, Minnesota by testing multiple water and bed material samples. This report also includes several tables and other figures.

This report describes results of a study to use stormwater data from four Miami, Florida catchménts to test applicability of deterministic modeling. It includes collected data, graphs, and maps.

Abstract: Most public water supplies sampled in Florida meet the National Interim Primary and Proposed Secondary Drinking Water Regulations. This conclusion is based on a water quality reconnaissance of 131 raw and treated public supplies throughout the State during the period January through May 1979. In a few public supplies, primary drinking water regulation maximum contaminant levels were exceeded for mercury, turbidity, and gross alpha particle activity. Secondary drinking water regulations were also occasionally exceeded in some public supplies for such parameters as chloride, pH, color, dissolved solids, iron, and manganese. These parameters, however, are more related to the aesthetic quality of drinking water than to public health aspects.

From purpose and study: The principal objectives of this study were as follows: (1) to determine the existing water-quality conditions in Lago Loiza as reflected by the principal chemical, physical, biological and bacteriological characteristics in the lake and its tributaries. (2) To estimate the reservoir's water budget during the study period, including the contributions from the tributaries and other sources. (3) Estimation of the reservoir's overall nitrogen and phosphorus budget, including the principal sources and sinks of these nutrients. (4) Definition of the sedimentation rate in the reservoir.

From abstract: This report presents "a water-quality study of the Neuse River, based on data collected during 1956-77 at the U.S. Geological Survey stations at Clayton and Kinston, employs statistical trend analysis techniques that provide a framework for river-quality assessment." It includes maps, graphs, and tables.

Abstract: Hydrologic data are being collected in four basins in the Warrior coal field to provide baseline information to aid in determining the effect mining will have on water resource Basins monitored are in two different geologic and hydrologic environments. Well yields from the Pottsville Formation generally range from 0 to 0.3 L/s, whereas well yields from the Coker Formation generally range from 0.3 L/s to 6.4 L/s. Streamflow distribute reflects seasonal precipitation. Streams draining basins underlain chiefly by the Pottsville Formation frequently go dry, whereas those draining basins underlain chiefly by the Coker Formation have well sustained low flows. Water in the Pottsville Formation is slightly acidic and moderately hard to very hard. Dissolved solids concentrations ranged from 176 to 268 mg/L. Water in the Coker Formation is soft, far less mineralized and more acidic than water in the Pottsville. Surface water is generally soft, acidic, and low in dissolved solids concentrations. Water in streams draining basins underlain chiefly by the Pottsville Formation was slightly more mineralized and less acidic than water in streams draining the Coker Formation.

From introduction: This report relates to the first of the above objectives by describing stream quality in the Yampa River basin through 1976, with particular emphasis on conditions from August 1975 through September 1976. The content of this report is, at times, relatively technical. This is intentional. The report is aimed not at planners and decision makers but rather at those persons assigned the task of having to design, implement, and interpret a river basin assessment. The techniques and procedures used to determine ambient stream quality in the Yampa River basin have been presented in detail so that their applicability to other river basins can be determined. For the planner and decision maker, the results presented in this report are summarized in less technical terms in phase-l (Steele and others, 1979) and phase-ll summary reports.

From abstract: Four modified nonradioactive-tracer methods and twenty predictive equations for determination of stream-reaeration coefficients (K2) in three small Wisconsin streams were compared with the radioactive-tracker methods developed by Tsivoglu.

Abstract: Sediments of Cretaceous to Holocene age compose the Northern Atlantic Coastal Plain aquifer system in an area of 50,000 square miles from North Carolina to New York. The aquifer system is the principal source of water supply for most of the area. About 1.4 billion gallons are withdrawn each day. Increasing pumpage has create~ problems such as declining water levels, saltwater intrusion, and land subsidence. The U.S. Geological Survey has begun a comprehensive study of the aquifer system that will define the geology, hydrology, and geochemistry of the system. The effects of future utilization of the aquifer system will be determined and alternative water withdrawal plans will be evaluated through computer simulation modeling. This report describes the objectives, organization, and work plans of the study.

This report presents "a technique for estimating the magnitude and frequency of floods in the Houston, Texas, metropolitan area." It includes a map, graph, and tables.

This report describes the results of a computer model simulation of the Potomac-Raritan-Magothy aquifer system in New Jersey to see "the effects of supplementing ground water from the Delaware River. It includes tables.

From abstract: A digital model was used to simulate the response of the Potomac-Raritan-Magothy aquifer system to pumping stresses during the 18-year period, 1956-73. The model was used to compute projected potentiometric heads and trends to the year 2000. Three sets of conditions were simulated: (1) no increase in ground-water extractions, (2) continued growth in ground-water extractions at the rate of 3 percent annually, and (3) continued growth in ground-water extractions at the rate of 3 percent annually, in conjunction with the activation of a freshwater head barrier in the fresh-salty water transition zone.

Water-quality data collected in the upper Oyster Creek drainage basin indicate that the stream has excellent water quality except for a persistently low pH. The mean concentrations of the major inorganic ions were all less than 6.0 mg/L. Mean concentrations of total nitrogen and total phosphorus were 0.15 mg/L and 0.01 mg/L, respectively. Dissolved oxygen averaged 8.7 mg/L and 81 percent saturation. Low pH levels are typical of streams draining cedar swamps. In Oyster Creek, the pH tended to decrease downstream due to chemical and biological processes. The pH levels in swamps were one-half unit or more lower than the pH levels in the adjacent stream. Sharp declines in stream pH were noted during runoff periods as the result of the mixing of poorly-buffered stream water with more highly acidic water from surrounding swamp areas. The quality of ground water within the study area was similar to the quality of stream flow, except for higher iron and ammonia-nitrogen concentrations and a higher pH range of 4.9-6.5. Precipitation represented a major source of many chemical constituents in the ground- and surface-waters of Oyster Creek basin.

From abstract: This report uses water samples collected from two sites at the Wild Rice River in Minnesota to "establish baseline water-quality characteristics before construction of a reservoir near Twin Valley, Minnesota for recreation and flood control." It contains a map, graphs, and tables.