This report examines the annual recharge to the Edwards Aquifer in San Antonio, Texas and how to collect annual recharge data. It includes maps and tables.

This report examines the effects of a highway construction project on suspended-sediment loads, concluding that the construction caused sixteen-thousand tons of sediment to be discharged and produced fifty percent of the total sediment discharge. It contains tables and graphs.

From abstract: This report presents collected data on daily water use for Florida in the year 1975 and includes several maps and tables.

From purpose and scope: The primary purpose of the study was to aid in evaluating the waste-load assimilative capacity of the study reach for a minimum mean 7-day low flow and 10-year recurrence interval. The results of this analysis will provide planners and managers in Routt County with information for determining the waste-load capacities of the study reach for possible design and operational alternatives of future wastewater-treatment plants.

Abstract: A general equation describing the three-dimensional transport and dispersion of a reacting solute in flowing ground water is derived from the principle of conservation of mass. The derivation presented in this report is more detailed but less rigorous than derivations published previously. The general solute-transport equation relates concentration changes to hydrodynamic dispersion, convective transport, fluid sources and sinks, and chemical reactions. Because both dispersion and convective transport depend on the velocity of ground-water flow, the solute-transport equation must be solved in conjunction with the ground-water flow equation.

Report and geological survey. This report is on the effects of the domestic secondary-treated effluent used for irrigation of pastures near Lakeland, Florida. Includes a number of maps, tables, and other figures.

Purposes of study and report: This report presents the results of a continuing study conducted by the U.S. Geological Survey in cooperation with the Denver Board of Water Commissioners. Purposes of the study are: (l) To define the amounts of net evaporation losses from the Denver storage reservoirs; and (2) to conduct experiments for improving methods for measuring evaporation, particularly at reservoirs at high elevations.

From introduction: The purpose of the study is to determine the effects of a new reservoir, Raystown Lake, on downstream low-flow frequency characteristics.

Report and Geological Survey. This report investigates the water quality of the shallow aquifer in Palm Beach County, Florida. It includes several maps, geophysical logs, and tables.

From purpose and scope: The purpose of this investigation is to document the types of aquatic benthic organisms found within the Everglades and to determine the extent to which the chemical and physical character of surface water and bottom materials affect their distribution and community structure.

From abstract: The Hueco Bolson provides a substantial part of the municipal and industrial water supply of the El Paso area of Texas, New Mexico and Mexico. Although the supply of fresh ground water in the bolson is large, about 10.6 million acre-feet (13,070 hm^3) in 1973 in the Texas part of the bolson alone, the supply is being depleted.

Recycling water within the local ground-water system is an effective means to increase quantity and control water temperature of the water supply and to control or avoid environmental pollution. A fish-rearing facility, operated for 15 months, returned water to the local ground-water system through an infiltration pond and recycled 83 percent of its water supply. For each 100 gallons pumped the net stress on the aquifer was equivalent to withdrawing 17 gallons. Despite recycling, nutrient content and temperature of the water supply were acceptable throughout the study period. The rearing-facility nutrient output ranged from 1 to 2 pounds of nitrate-nitrogen per day, but nitrate-nitrogen levels in the water supply remained below 4 mg/1. The water temperature ranged from 7°C to 14°C. Mathematical relations developed show that acceptable nitrate-nitrogen levels and water temperatures nearly optimum for salmonid rearing could be maintained during full-scale hatchery operation.

Abstract: Rainfall and runoff data from drainage basins in the Houston metropolitan area and a 60-year rainfall record for the National Weather Service station, Houston-City, were used to simulate 60 annual flood peaks at 26 sites. Selected frequency characteristics, based on these simulated annual peaks are related to drainage area and percentage of impervious area. These relations which may be used to estimate the flood characteristics at ungaged sites, indicate that in the Houston metropolitan area, complete urbanization increases the magnitude of a 2-year flood nine times and increases the magnitude of a 50-year flood five times.

Abstract: A method which relates basin characteristics with peak flow characteristics is presented for determining magnitude and frequency of floods on streams with drainage areas between 0.5 and 200 square miles. Regression equations for each of eight regions are presented for determination of the 10-year flood. Peak flows for the 25- and 50-year floods can then be estimated from ratios developed for each region. Regression equations are not developed because of poor definitions for several areas that total about 20,000 square miles. The equations were based on multiple-regression techniques using annual peaks and basin characteristics for 303 gaged sites.