Purpose and Scope: The purpose of this study was to evaluate the geohydrologic characteristics that influence sustained artificial recharge and to determine long-term infiltration rates in the northern part of Chino ground-water basin. Results of this study will help management to design and implement a recharge-recapture system in Chino Basin. Nine test holes were drilled, long-term infiltration tests were made, and drillers' logs and water-level data were evaluated to determine the probable effects of recharging the ground-water basin. The study was concentrated in the northern part of Chino Basin, where recharge is proposed.

From introduction: The purpose of this report is to provide methods for estimating mean annual runoff and peak discharges for ungaged streams in northeastern and western Montana.

Objectives and scope: The principal objectives of this study were to assess the past and current water quality of the impoundment, its major tributaries, and its discharge, and to address the environmental impact of raised pool levels. Data collection was directed toward documenting the temporal and spatial variations in physical, chemical, and biological characteristics of the water, to estimate annual nutrient and suspended sediment loading, and to determine the algal biomass, dominant genera, algal growth potential, and limiting nutrient.

From abstract: This report presents chemical-quality data collected from May 1980 to January 1981 at several locations within the Delaware River estuary and selected New Jersey tributaries.

From introduction: This study is part of a regional study of the Tertiary limestone aquifer system in the southeastern United States. The regional study encompasses all of Florida and extends into Georgia, Alabama, and South Carolina--a total area of about 82,000 square miles.

Abstract: Alimagnet, Farquar, and Long Lakes, in Apple Valley, Minnesota, were sampled from 1973-79 to determine their physical and chemical characteristics. A storm-sewer inlet to Alimagnet Lake was also sampled during two storms in 1978. The 1976-77 drought caused a more noticeable effect on the quality of the lakes than any other factor. Chloride concentrations were 10 to 15 milligrams per liter before the drought, but increased 2 to 4 times during the drought. Dissolved solids reacted similarly . Dissolved oxygen and pH were governed mainly by biological activity. In February 1977, dissolved-oxygen concentration was less than 0.5 milligrams per liter in the three lakes. Ratios between mean total nitrogen and mean total phosphorus ranged from 22:1 to 26:1. Tropic-state indices indicate that the lakes are eutrophic. Blue-green algae dominated the phytoplankton populations. Storms sampled at a storm-sewer inlet to Alimagnet Lake showed higher concentrations pf chromium, copper, nickel, and zinc than of lead, arsenic, cadmium, and mercury. Total phosphorus for the September 1978 storm had a concentration of 1.7 milligrams per liter, which means that approximately 29 pounds entered the lake during the 5.5-hour sampling period.

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.

From abstract: The stratigraphic nomenclature of the central Santa Monica Mountains is revised to conform with present knowledge of the age, distribution, and stratigraphic relations of about 35 bedrock units. The revision is based on 1:12,000-scale mapping of the entire stratigraphic sequence and its facies, the position and stage assignment of abundant fossils, and contact relations.

This report used "annual peak-discharge records at fifty sites with five or more years of record" to determine individual site frequency curves. It includes several maps.

From introduction: The primary objective of this study, second in the series, is the development, calibration, and verification of flow-routing models for the Susquehanna River from Waverly, New York, to Sunbury, Pennsylvania. These models will permit SRBC to estimate the effects of water-resource developments upstream from Waverly at six locations on the Susquehanna River. They were also used to simulate for existing conditions at two ungaged sites.

This report provides a detailed survey of the artesian aquifer that acts as the main source of water "for Brooks, Lowndes, and western Eocene Counties in south Georgia." It includes maps, tables, and graphs.

This report provides an evaluation of sediment transport by the White River into Mud Mountain Reservoir during the two-year period of June 1974 and June 1976. It includes graphs and tables.

This report presents a "digital model used to simulate ground-water flow in the aquifer system in a basin drained by Piceance and Yellow Creeks, Colorado." It includes maps, diagrams, and tables.

This report examines the water quality of water within the Miami Canal, an important source of recharge for the recharge for the Biscayne aquifer. It includes maps and other figures.

"This report presents flood heights and profiles for a seventy-mile reach of Peace River from Bartow to Arcadia," Florida, "calculated using the United States Geological Survey step-backwater model." It includes maps, graphs, and tables.

This report focuses on the Nevin Wetland near Madison, Wisconsin and presents a detailed report on the quality of the ground-water, it's components, and what environmental factors influence these components. It includes maps and tables.

From purpose and scope: This report describes the hydrology of selected spring ponds and the effect that dredging has had on the ponds and their surrounding areas. The report emphasizes the water budgets for the ponds, discusses the hydrologic system which contains the ponds, and briefly describes water quality in the study area.

From introduction: The purpose of the low-flow characteristics are in some instances affected by the period of record. These characteristics can vary as much as +/- 30 percent at some gaging stations depending on whether or not the severe drought of the 1930's was included in the analysis.

From purpose and scope: This report describes methods for evaluating the magnitude and frequency of floods at gaged and (or) ungaged sites in California. The purpose is to provide a base for the study of floods and the review and extension of flood magnitude-frequency relations by agencies and individuals who are concerned with the management and control of floods, highway construction, and other related work.

From introduction: The purpose of the study was to assemble data on the occurrence, movement, availability and chemical quality of ground water in the Hackensack River basin in Bergen and Hudson Counties, New Jersey; to evaluate and interpret the data; and to make the results available to the public.

From introduction: The purpose of this investigation is to collect and interpret the basic hydrologic and geologic data and to appraise and report on the ground-water resources of Camden County. The objectives were to define the thickness and areal extent of the hydrologic units, evaluate the hydraulic characteristics of the aquifers, determine the effect of pumpage on the water levels of the area, define the source of recharge of the aquifers, and to evaluate the chemical quality of the ground water.

From purposes and scope: The purposes of this investigation are to make a qualitative assessment of the effects on water quality of pumping water into the conservation areas, and specifically to evaluate the uptake by sediment and biota of nitrogen, phosphorus, and selected trace elements contained in the water.