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R.S. Sonenshein

Publications and source records attributed to R.S. Sonenshein.

10 recordsLinked to original sources
USGS2001

Methods to quantify seepage beneath Levee 30, Miami-Dade County, Florida

A two-dimensional, cross-sectional, finite-difference, ground-water flow model and a simple application of Darcy?s law were used to quantify ground-water flow (from a wetlands) beneath Levee 30 in Miami-Dade County, Florida. Geologic and geophysical data, vertical seepage data from the wetlands, canal discharge data, ground-water-level data, and surface-water-stage data collected during 1995 and 1996 were used as boundary conditions and calibration data for the ground-water flow model and as input for the analytical model. Vertical seepage data indicated that water from the wetlands infiltrated the subsurface, near Levee 30, at rates ranging from 0.033 to 0.266 foot per day when the gates at the control structures along Levee 30 canal were closed. During the same period, stage differences between the wetlands (Water Conservation Area 3B) and Levee 30 canal ranged from 0.11 to 1.27 feet. A layer of low-permeability limestone, located 7 to 10 feet below land surface, restricts vertical flow between the surface water in the wetlands and the ground water. Based on measured water-level data, ground-water flow appears to be generally horizontal, except in the direct vicinity of the canal. The increase in discharge rate along a 2-mile reach of the Levee 30 canal ranged from 9 to 30 cubic feet per second per mile and can be attributed primarily to ground-water inflow. Flow rates in Levee 30 canal were greatest when the gates at the control structures were open. The ground-water flow model data were compared with the measured ground-water heads and vertical seepage from the wetlands. Estimating the horizontal ground-water flow rate beneath Levee 30 was difficult owing to the uncertainty in the horizontal hydraulic conductivity of the main flow zone of the Biscayne aquifer. Measurements of ground-water flows into Levee 30 canal, a substantial component of the water budget, were also uncertain, which lessened the ability to validate the model results. Because of vertical flows near Levee 30 canal and a very low hydraulic gradient east of the canal, a simplified Darcian approach simulated with the ground-water flow model does not accurately estimate the horizontal ground-water flow rate. Horizontal ground-water flow rates simulated with the ground-water flow model (for a 60-foot-deep by 1-foot-wide section of the Biscayne aquifer) ranged from 150 to 450 cubic feet per day west of Levee 30 and from 15 to 170 cubic feet per day east of Levee 30 canal. Vertical seepage from the wetlands, within 500 feet of Levee 30, generally accounted for 10 to 15 percent of the total horizontal flow beneath the levee. Simulated horizontal ground-water flow was highest during the wet season and when the gates at the control structures were open.

Florida↗
USGS1996

Documentation of programs used to determine a wetlands hydroperiod from model-simulated water-surface elevations

A technique has been developed to determine a wetlands hydroperiod by comparing simulated water levels from a ground-water flow model and land- surface elevation data through a geographic information system. The simulated water levels are compared with the land-surface elevation data to determine the height of the water surface above or below land surface for the area of interest. Finally, the hydroperiod is determined for established time periods using criteria specified by the user. The program application requires the use of geographic information system software (ARC/INFO), including the TIN and GRID subsystems of the software. The application consists of an ANSI compatible C program to translate ground- water data output from the U.S. Geological Survey modular three-dimensional, finite-difference, ground-water flow model (MODFLOW) into a format that can be used as input for the geographic information system programs (AML's). The application uses ARC/INFO AML programs and ARC/INFO menu interface programs to create digital spatial data layers of the land surface and water surface and to determine the hydroperiod. The technique can be used to evaluate and manage wetlands hydrology.

Open-File Report↗
USGS1995

A hydrogeologic approach to identify land uses that overlie ground-water flow paths, Broward County, Florida

A hydrogeologic approach that integrates the use of hydrogeologic and spatial tools aids in the identification of land uses that overlie ground- water flow paths and permits a better understanding of ground-water flow systems. A mathematical model was used to simulate the ground-water flow system in Broward County, particle-tracking software was used to determine flow paths leading to the monitor wells in Broward County, and a Geographic Information System was used to identify which land uses overlie the flow paths. A procedure using a geographic information system to evaluate the output from a ground-water flow model has been documented. The ground-water flow model was used to represent steady-state conditions during selected wet- and dry-season months, and an advective flow particle- tracking program was used to simulate the direction of ground-water flow in the aquifer system. Digital spatial data layers were created from the particle pathlines that lead to the vicinity of the open interval of selected wells in the Broward County ground-water quality monitoring network. Buffer zone data layers were created, surrounding the particle pathlines to represent the area of contribution to the water sampled from the monitor wells. Spatial data layers, combined with a land-use data layer, were used to identify the land uses that overlie the ground-water flow paths leading to the monitor wells. The simulation analysis was performed on five Broward County wells with different hydraulic parameters to determine the source of ground-water stress, determine selected particle pathlines, and identify land use in buffer zones in the vicinity of the wells. The flow paths that lead to the grid cells containing wells G-2355, G-2373, and G-2373A did not vary between the wet- and dry-season conditions. Changes in the area of contribution for wells G-2345X and G-2369 were attributed to variations in rainfall patterns, well-field pumpage, and surface-water management practices. Additionally, using a different open interval at a site, such as for wells G-2373 and G-2373A, can result in a very different area that overlies the flow path leading to the monitor well.

Water-Resources Investigations Report↗
USGS1994

Spatial and temporal statistical analysis of a ground-water level network, Broward County, Florida

The U.S. Geological Survey has developed a method to evaluate the spatial and temporal statistics of a continuous ground-water level recorder network in Broward County, Florida. Because the Broward County network is sparse for most spatial statistics, a technique has been developed to define polygons for each well that represent the area monitored by the well within specified criteria. The boundaries of these "confidence polygons" are defined by the endpoints of radial lines oriented toward the other wells. The lengths of these lines are determined as the statistically estimated distances to the points at which ground-water levels can be predicted within specirfied criteria. The confidence polygons indicate: (1) the areal coverage of the network, (2) locations where data are unavailable, and (3) areas of redundant data collection. Comparison with data from a noncontinuous recorder well indicates that the confidence polygons are a good represen- tation of areal coverages. The temporal analysis utilizes statistical techniques similar to those used in the spatial method, defining variations in time rather than in space. Consequently, instead of defining radial distances to points, time intervals are defined over which water-level values can be predicted within a specified confidence. These "temporal confidence intervals" correspond to maximum allowable periods between field measure- ments. To combine all results from the analyses, a single coefficient reflecting the spatial and temporal results has been developed. The coefficient is referred to as the Spatial and Temporal Adequacy and Redundancy Evaluation (STARE) and is determined by three factors: the size of the confidence polygon, the number of times the well is part of a redundant pair, and the temporal confidence interval. This coefficient and the individual results of each analysis are used in evaluating the present network and determining future management decisions.

Florida↗
USGS1992

Documentation of a digital spatial data base for hydrologic investigations, Broward County, Florida

Geographic information systems have become an important tool in planning for the protection and development of natural resources, including ground water and surface water. A digital spatial data base consisting of 18 data layers that can be accessed by a geographic information system was developed for Broward County, Florida. Five computer programs, including one that can be used to create documentation files for each data layer and four that can be used to create data layers from data files not already in geographic information system format, were also developed. Four types of data layers have been developed. Data layers for manmade features include major roads, municipal boundaries, the public land-survey section grid, land use, and underground storage tank facilities. The data layer for topographic features consists of surveyed point land-surface elevations. Data layers for hydrologic features include surface-water and rainfall data-collection stations, surface-water bodies, water-control district boundaries, and water-management basins. Data layers for hydrogeologic features include soil associations, transmissivity polygons, hydrogeologic unit depths, and a finite-difference model grid for south-central Broward County. Each data layer is documented as to the extent of the features, number of features, scale, data sources, and a description of the attribute tables where applicable.

Florida↗
USGS1990

Hydrologic effects of well-field operations in a wetland, Dade County, Florida

Water-level, canal stage and discharge, and rainfall data collected in a wetland in Dade County, Florida, were analyzed to determine the effects of pumping at the Northwest Well Field on water levels in the wetland. The Northwest Well Field is the first major well field in south Florida to be operated in a wetland, away from saltwater intrusion and the potential for contamination caused by urbanization. Duration curves were used to analyze trends in water levels for seven observation wells near the Northwest Well Field. One observation well is 5.5 miles north of the well field, three wells are outside the cone of depression of the well field, and three are within the cone of depression. The water level data were analyzed for four time periods that were determined by a double-mass analysis of cumulative rainfall and cumulative canal discharge. Before 1984, water levels in all seven wells were above land surface 25 to 50 percent of the time. Since the well field began operating in 1984, water levels in the three wells within the cone of depression have been above land surface less than 1 percent of the time. Water levels at the four wells outside the cone of depression showed no effect from pumping at the well field. Water levels have declined in 30 percent of the 65- square mile study area since the well field began operating. In 15 percent of the area, water levels have been lowered below land surface.

Water-Resources Investigations Report↗
USGS1988

Water resources data for Florida, water year 1987. Volume 2B. South Florida ground water

Water resources data for the 1987 water year in Florida consists of continuous or daily discharge for 320 streams, periodic discharge for 38 streams, miscellaneous discharge for 29 streams, continuous or daily stage for 94 streams, periodic stage for 48 streams, peak discharge for 76 streams and peak stage for 69 streams; continuous or daily elevations for 80 lakes, periodic elevations for 74 lakes; continuous ground-water levels for 477 wells, periodic ground-water levels for 562 wells, and miscellaneous water level measurements for 2,886 wells; quality of water data for 223 surface-water sites and 900 wells. The data for South Florida include continuous or daily discharge for 47 streams, periodic discharge for 2 streams, peak discharge for 4 streams, continuous or daily stage for 63 streams, periodic stage for 16,streams, peak discharge for 3 streams, and peak stage for 12 streams; continuous elevations for 1 lake, and periodic elevations for 5 lakes; continuous ground-water levels for 169 wells, periodic ground-water levels for 213 wells, and miscellaneous water-level measurements for 388 wells; quality-of-water for 10 surface-water sites and 521 wells. This data represent the National Water Data System records collected by the U.S. Geological Survey and cooperation local, state and federal agencies in Florida.

Florida↗
USGS1986

Index of hydrologic data for selected sites in Palm Beach County, Florida, 1928-80

A regional assessment of the surficial aquifers in Dade, Broward , and Palm Beach Counties, Florida, including the Biscayne aquifer, was begun in 1979 by the U.S. Geological Survey, in cooperation with the South Florida Water Management District. The purpose of the first phase of the project was to determine the geologic, hydrologic, and water quality data available in the files of the U.S. Geological Survey and other public agencies. This report summarizes, through tables and maps, the types of data available for Palm Beach County.

Florida↗