Publications

Purpose The South Florida Ecosystem Restoration Program is an intergovernmental effort to reestablish and maintain the ecosystem of south Florida. One element of the restoration effort is the development of a firm scientific basis for resource decision making. The U.S. Geological Survey (USGS) is one of the agencies that provides scientific information as part of the South Florida...

Background The embayments and estuaries of Florida's southwest coast are an integral part of the south Florida ecosystem. Nutrients and other constituents are transported to these coastal waters by surface water and ground-water flow from the Everglades National Park (ENP) and the Big Cypress Preserve and by longshore and offshore tidal currents. The coastal area is an essential breeding...

Background The major issues facing ecosystem restoration and management in south Florida are centered on the availability and distribution of clean, fresh water. Surface water flow modeling studies are an important aspect of the scientific information needs of the ecosystem restoration initiative. Hydrologic models provide much needed predictive capabilities for evaluating options for...

A model parameter set for use with the Hydrologic Simulation Program FORTRAN watershed model was developed to simulate storm peaks and storm volumes for the 28 subbasins of the West Fork Trinity River Basin upstream from Lake Worth, northwest of Fort Worth, Texas, from the calibration and testing of 5 gaged subbasins. These parameters can be transferred to the 23 ungaged subbasins. The...

A water-surface-elevation profile and peak discharges for the flood of May 19, 1990, along Perry Creek in Plymouth and Woodbury Counties, Iowa, are presented in this report. The peak discharge for the May 19,1990, flood on Perry Creek at 38th Street, Sioux City (06600000) is the second largest flood-peak discharge recorded at the streamflow-gaging station for the period 1939-95. The peak...

The Southeastern Coastal Plain aquifer system consists of a thick sequence of unconsolidated to poorly consolidated Cretaceous and Tertiary rocks that extend from Mississippi to South Carolina. Four regional sand and gravel aquifers are separated by three regional confining units of clay, shale, and chalk that do not conform everywhere to stratigraphic boundaries. The change in geologic...

An understanding of the magnitude and frequency of low-flow discharges is an important part of protecting surface-water resources and planning for municipal and industrial economic expansion. Low-flow characteristics are summarized for 22 continuous-record gaging stations in North Carolina (19 sites) and Virginia (3 sites) and 60 partial-record gaging stations in the North Carolina...

The U.S. Geological Survey, in cooperation with the National Soil Tilth Laboratory of the U.S. Department of Agriculture, Agricultural Research Service, conducted a study as part of the multi-scale, inter-agency Management Systems Evaluation Area (MSEA) program to evaluate the effects of agricultural management (farming) systems on water quality. Data on surface flow, tileflow, and...

The Edwards aquifer in the San Antonio region supplies drinking water for more than 1 million people. Proper development and protection of the aquifer is a high priority for local and State authorities. To better understand the flow of water in two major flowpaths in the Edwards aquifer, stratigraphic, structural, hydrologic, and geochemical data were analyzed. The western Medina...

As of September 30, 1995, the surface-water data-collection network of Texas (table 1) included 305 continuous-recording streamflow stations (D), 28 gageheight record only stations (G), 23 crest-stage partialrecord stations (C), 42 flood-hydrograph partial-record stations (H), 33 low-flow partial-record stations (L), 19 continuous-recording temperature and conductivity stations (M2), 5...

Eggs from four aquatic bird species nesting in the Lower Laguna Madre, Texas, were collected to determine differences and similarities in the accumulation of congener-specific polychlorinated biphenyls (PCBs) and to evaluate PCB impacts on reproduction. Because of the different toxicities of PCB congeners, it is important to know which congeners contribute most to total PCBs. The...

Isla del Coco lies at 5 degrees 32'N latitude, 87 degrees 04'W longitude and is the sole peak of the Cocos Ridge exposed above sea level. This isolated island formed approximately 2 million years ago. It rises 575 m above the surface of the sea and covers 46 km2 (Castillo et aI., 1988). Five hundred km to the NNE is Costa Rica; 630 km SSW are the Galapagos Islands; 650 km to the E is...