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Source-linked reports with geographic coverage including Florida.

At least 1,621 records · Page 90Linked to original sources
USGS1991

Water resources data, Florida, water year 1990. Volume 1A. Northeast Florida surface water

Water resources data for the 1990 water year in Florida consist of continuous or daily discharge for 349 streams, periodic discharge for 40 streams, miscellaneous discharge for 75 streams, continuous or daily stage for 105 streams, continuous daily tide stage for 12 sites, periodic stage for 25 streams, peak discharge for 41 streams, and peak stage for 40 streams; continuous or daily elevations for 70 lakes, periodic elevations for 70 lakes; continuous ground-water levels for 441 wells, periodic ground-water levels for 1,229 wells, and miscellaneous water-level measurements for 1,908 wells; quality-of-water data for 145 surface-water sites and 799 wells. The data for northeast Florida include continuous or daily discharge for 164 streams, periodic discharge for 27 streams, miscellaneous discharge for 22 streams, continuous or daily stage for 2 streams, continuous or daily tide stage for 3 sites, periodic stage for 13 streams, peak discharge for 17 streams, and peak stage for 30 streams; continuous or daily elevations for 41 lakes, periodic elevations for 53 lakes; continuous ground-water levels for 76 wells, periodic ground-water levels for 161 wells, and miscellaneous water-level measurements for 878 wells; quality-of-water data for 51 surface-water sites and 78 wells. These data represent the National Water Data System records collected by the U.S. Geological Survey and cooperating local, state and federal agencies in Florida.

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USGS1991

Water resources data, Florida; Water year 1990; Volume 2A. South Florida surface water

Water resources data for the 1990 water year in Florida consists of continuous or daily discharge for 349 streams, periodic discharge for 40 streams, miscellaneous discharge for 75 streams, continuous or daily stage for 105 streams, periodic stage tor 25 streams, peak discharge for 41 streams, continuous daily tide stage for 12 streams, and peak stage for 40 streams, continuous or daily elevations for 70 lakes, periodic elevations for 70 lakes; continuous ground-water levels for 441 wells, periodic ground-water levels for 1,229 wells, and miscellaneous water level measurements for 1,908 wells; quality of water data for 145 surface-water sites and 799 wells. The data for South Florida included continuous or daily discharge for 75 streams, continuous or daily stage for 84 streams, continuous elevation for 2 lake; continuous groundwater levels for 184 wells, periodic ground-water levels for 873 wells, and miscellaneous water-level measurements for 317 wells; quality-of-water for 15 surface-water sites and 541 wells. This data represent the National Water Data System records collected by the U.S. Geological Survey and cooperating local, state, and federal agencies in Florida.

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USGS1991

Water resources data, Florida, water year 1990. Volume 2B. South Florida ground water

Water resources data for the 1990 water year in Florida consists of continuous or daily discharge for 349 streams, periodic discharge for 40 streams, miscellaneous discharge for 75 streams, continuous or daily stage for 105 streams, periodic stage for 25 streams, peak discharge for 41 streams, continuous daily tide stage for 12 streams, and peak stage for 40 streams, continuous or daily elevations for 70 lakes, periodic elevations for 70 lakes; continuous ground-water levels for 441 wells, periodic ground-water levels for 1,229 wells, and miscellaneous water level measurements for 1,908 wells; quality of water data for 145 surface-water sites and 799 wells. The data for South Florida include continuous or daily discharge for 75 streams, continuous or daily stage for 84 streams, continuous elevation for 1 lake; continuous ground-water levels for 184 wells, periodic ground-water levels for 873 wells, and miscellaneous water-level measurements for 317 wells; quality-of-water for 15 surface-water sites and 541 wells. This data represent the National Water Data System records collected by the U.S. Geological Survey and cooperation with local, state, and federal agencies in Florida.

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USGS1991

Water resources data, Florida, water year 1990. Volume 3A: Southwest Florida surface water

Water resources data for the 1990 water year in Florida consist of continuous or daily discharge for 349 streams, periodic discharge for 40 streams, miscellaneous discharge for 75 streams, continuous or daily stage for 105 streams, continuous daily tide stage for 12 sites, periodic stage for 25 streams, peak discharge for 41 streams and peak stage for 40 streams; continuous or daily elevations for 70 lakes, periodic elevations for 70 lakes; continuous ground-water levels for 441 wells, periodic ground-water levels for 1,229 wells, and miscellaneous water-level measurements for 1,908 wells; quality-of-water data for 145 surface-water sites and 799 wells. The data for southwest Florida include records of stage, discharge, and water quality of streams; stage, contents, water quality of lakes and reservoirs, and water levels and water quality of ground-water wells. Volume 3A contains continuous or daily discharge for 59 streams, periodic discharge for 7 streams, miscellaneous discharge for 2 streams, continuous daily stage for 22 streams, periodic stage for 2 streams, peak discharge for 30 streams, continuous elevation for 20 lakes, periodic elevation for 15 lakes, and quality-of-water for 62 surface-water sites. These data represent the National Water Data System records collected by the U.S. Geological Survey and cooperating, local, state and federal agencies in Florida.

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USGS1991

Water resources data, Florida, water year 1990. Volume 3B: Southwest Florida ground water

Water resources data for the 1990 water year in Florida consist of continuous or daily discharge for 349 streams, periodic discharge for 40 streams, miscellaneous discharge for 75 streams, continuous or daily stage for 105 streams, continuous daily tide stage for 12 sites, periodic stage for 25 streams, peak discharge for 41 streams, and peak stage for 40 streams; continuous or daily elevations for 70 lakes, periodic elevations for 70 lakes; continuous ground-water levels for 441 wells, periodic ground-water levels for 1229 wells and miscellaneous water-level measurements for 1908 wells; quality-of-water data for 145 surface-water sites and 799 wells. The data for southwest Florida include records of stage, discharge, and water quality of streams; stage, contents, water quality of lakes and reservoirs, and water levels and water quality of ground-water wells. Volume 3B contains records for continuous ground-water elevations for 172 wells; periodic ground-water elevations at 144 wells; miscellaneous ground-water elevations at 842 wells; and water quality at 148 ground-water sites. These data represent the national Water Data System records collected by the U.S. Geological Survey and cooperating local, state, and federal agencies in Florida.

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USGS1991

Water resources data, Florida, water year 1991. Volume 1B: Northeast Florida ground water

Water resources data for the 1991 water year in Florida consist of continuous or daily discharge for 346 streams, periodic discharge for 27 streams, miscellaneous dis-charge for 50 streams, continuous or daily stage for 151 streams, continuous daily tide stage for 3 sites, periodic stage for 29 streams, peak discharge for 23 streams, and peak stage for 16 streams; continuous or daily elevations for 64 lakes, periodic elevations for 67 lakes; continuous ground-water levels for 436 wells, periodic ground-water levels for 1,172 wells, and miscellaneous water-level measurements for 1,628 wells; quality-of-water data for 139 surface-water sites and 761 wells. The data for northeast Florida include continuous or daily discharge for 155 streams, periodic discharge for 12 streams, miscellaneous discharge for 18 streams, continuous or daily stage for 30 streams, continuous or daily tide stage for 3 sites, periodic stage for 23 streams, peak discharge for 3 streams, and peak stage for 11 streams; continuous or daily elevations for 38 lakes, periodic elevations for 48 lakes; continuous ground-water levels for 75 wells, periodic ground-water levels for 144 wells, and miscellaneous water-level measurements for 871 wells; quality-of-water data for 50 surface-water sites and 72 wells. These data represent the National Water Data System records collected by the U.S. Geological Survey and cooperating local, state and federal agencies in Florida.

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USGS1991

Hydrogeology of the surficial aquifer system, Dade County, Florida

An investigation of the surficial aquifer system in Dade County, begun in 1983, is part of a regional study of the aquifer system in southeastern Florida. Test drilling for lithologic samples, flow measurements during drilling, aquifer testing, and analyses of earlier data permitted delineation of the hydraulic conductivity distribution (on hydrogeologic sections), the aquifers in the system, the generalized transmissivity distribution, and interpretation of the ground-water flow system. The surficial aquifer system, in which an unconfined ground-water flow system exists, is composed of the sediments from land surface downward to the top of a regionally extensive zone of sediments of low permeability called the intermediate confining unit. The aquifer system units, which vary in composition from clay-size sediments to cavernous limestone, are hydro stratigraphically divided into the Biscayne aquifer at the top; an intervening semiconfining unit that consists principally of clayey sand; a predominantly gray limestone aquifer in the Tamiami Formation in western and west-central Dade County; and sand or clayey sand near the base of the surficial aquifer system. The base of the surficial aquifer system ranges from a depth of about 175 to 210 feet below land surface in westernmost Dade County to greater than 270 feet in northeastern Dade County. Test drilling and aquifer-test data indicate a complex hydraulic conductivity distribution. Hydraulic conductivities of the very highly permeable zone of the Biscayne aquifer commonly exceed 10,000 feet per day; in the gray limestone aquifer, they range from 210 to 780 feet per day. Transmissivities of the surficial aquifer system vary locally but have a recognizable areal trend. Estimated values generally are about 300,000 feet squared per day or greater in nearly all of central and eastern Dade County. Transmissivity is lower to the west, decreasing to less than 75,000 feet squared per day in western Dade County. High transmissivity usually is associated with thick sections of the Fort Thompson Formation within the Biscayne aquifer. The gray limestone aquifer of the Tamiami Formation has transmissivities that range from 5,800 to 39,000 feet squared per day in western Dade County. The transition from high transmissivity to relatively low transmissivity is often only a few miles wide and coincides with the decrease in thickness of the very highly permeable Fort Thompson Formation, which marks the western boundary of the Biscayne aquifer. More effective drainage as a result of extensive canal systems and large-scale pumping from municipal well fields has greatly altered the predevelopment flow system in eastern Dade County by: (1) eliminating or greatly reducing a seasonal and coastal ground-water ridge; (2) reducing deep circulation; (3) reducing or eliminating seasonal westward movement of ground water; (4) causing accelerated stormwater runoff and short ground-water flow paths; and (5) generally lowering the water table and inducing saltwater intrusion. Under predevelopment conditions in western Dade County, water entered the gray limestone aquifer by lateral movement from Broward and Collier Counties, and by downward seepage from The Everglades and the Biscayne aquifer, and moved southward and southeastward into Dade County to coastal discharge areas. Circulation in the Biscayne aquifer inland also was primarily to the south and southeast. In eastern Dade County, the seasonal ground-water ridge that formed under predevelopment conditions supported both easterly and westerly ground-water flow away from the ridge axis. This seasonal flow created a zone of lower dissolved solids.

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USGS1991

Major-ion and selected trace-metal chemistry of the Biscayne Aquifer, Southeast Florida

The major-ion and selected trace-metal chemistry of the Biscayne aquifer was characterized as part of the Florida Ground-Water Quality Monitoring Network Program, a multiagency cooperative effort concerned with delineating baseline water quality for major aquifer systems in the State. The Biscayne aquifer is unconfined and serves as the sole source of drinking water for more than 3 million people in southeast Florida. The Biscayne aquifer consists of highly permeable interbedded limestone and sandstone of Pleistocene and Pliocene age underlying most of Dade and Broward Counties and parts of Palm Beach and Monroe Counties. The high permeability is largely caused by extensive carbonate dissolution. Water sampled from 189 wells tapping the Biscayne aquifer was predominantly a calcium bicarbonate type with some mixed types occurring in coastal areas and near major canals. Major - ion is areally uniform throughout the aquifer. According to nonparametric statistical tests of major ions and dissolved solids, the concentrations of calcium, sodium, bicarbonate, and dissolved solids increased significantly with well depth ( 0.05 significance level ), probably a result of less circulation at depth. Potassium and nitrate concentrations decreased significantly with depth. Although the source of recharge to the aquifer varies seasonally, there was no statistical difference in the concentration of major ions in pared water samples from 27 shallow wells collected during wet and dry seasons. Median concentrations for barium, chromium, copper, lead, and manganese were below maximum or secondary maximum contaminant levels set by the US Environmental Protection Agency. The median iron concentration only slightly exceeded the secondary maximum contaminant level. The concentration of barium was significantly related (0.05 significance level) to calcium and bicarbonate concentration. No distinct areal pattern or vertical distribution of the selected trace metals was evident in water from the Biscayne aquifer. Sources for trace metals found in water from the Biscayne aquifer may include local contamination, well-construction techniques, canal - aquifer interactions, and natural occurrence in area soils and rock.

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USGS1991

Tidal-flow, circulation, and flushing changes caused by dredge and fill in Hillsborough Bay, Florida

Hillsborough Bay, Florida, underwent extensive physical changes between 1880 and 1972 because of the construction of islands, channels, and shoreline fills. These changes resulted in a progressive reduction in the quantity of tidal water that enters and leaves the bay. Dredging and filling also changed the magnitude and direction of tidal flow in most of the bay. A two-dimensional, finite-difference hydrodynamic model was used to simulate flood, ebb, and residual water transport for physical conditions in Hillsborough Bay and the northeastern part of Middle Tampa Bay during 1880, 1972, and 1985. The calibrated and verified model was used to evaluate cumulative water-transport changes resulting from construction in the study area between 1880 and 1972. The model also was used to evaluate water-transport changes as a result of a major Federal dredging project completed in 1985. The model indicates that transport changes resulting from the Federal dredging project are much less areally extensive than the corresponding transport changes resulting from construction between 1880 and 1972. Dredging-caused changes of more than 50 percent in flood and ebb water transport were computed to occur over only about 8 square miles of the 65-square-mile study area between 1972 and 1985. Model results indicate that construction between 1880 and 1972 caused changes of similar magnitude over about 23 square miles. Dredging-caused changes of more than 50 percent in residual water transport were computed to occur over only 17 square miles between 1972 and 1985. Between 1880 and 1972, changes of similar magnitude were computed to occur over an area of 45 square miles. Model results also reveal historical tide-induced circulation patterns. The patterns consist of a series of about 8 interconnected circulatory features in 1880 and as many as 15 in 1985. Dredging- and construction-caused changes in number, size, position, shape, and intensity of the circulatory features increase tide-induced circulation throughout the bay. Circulation patterns for 1880, 1972, and 1985 levels of development differ in many details, but all exhibit residual landward flow of water in the deep, central part of the bay and residual seaward flow in the shallows along the bay margins. This general residual flow pattern is confirmed by both computed transport of a hypothetical constituent and long-term salinity observations in Hillsborough Bay. The concept has been used to estimate the average time it takes a particle to move from the head to the mouth of the bay. The mean transit time was computed to be 58 days in 1880 and 29 days in 1972 and 1985. This increase in circulation and decrease in transit time since 1880 is estimated to have caused an increase in average salinity of Hillsborough Bay of about 2 parts per thousand. Dredge and fill construction is concluded to have significantly increased circulation and flushing between 1880 and 1972. Little circulation or flushing change is attributed to dredging activity since 1972.

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USGS1991

Paleoshorelines, reefs, and a rising sea: South Florida, USA

The porous limestone bedrock, thin sediment cover, and tectonic stability of the Florida Platform during the past 15 ka BP provide an exceptionally suitable setting for reconstruction of paleoshorelines and onshore projection of future shorelines in a rising-sea scenario. Paleoshorelines for 8, 6, 4 and 2 ka BP show that 1) a series of limestone islands formed, then drowned, along the outer platform; 2) a distinct trough, called Hawk Channel, separated the outer islands from shore; 3) the lower Keys flooded earlier and more rapidly than the rest of the Keys; and 4) Florida Bay and tidal passes through the middle Keys into the bay developed within the past 4 ka BP. Projection of future shorelines onto land shows that most land forming the Florida Keys would flood in a rise of 1 to 2 m and that a rise of little more than 5 m would submerge all land. Offshore reefs would die, while nearshore reefs would shift landward as the mainland shoreline migrated northward. -from Authors

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USGS1991

Impact of exploratory wells, offshore Florida: A biological assessment

Seven offshore exploratory oil well sites were examined in an effort to determine the ecological impact of exploratory drilling on the subtropical marine ecosystems of southern Florida, including seagrass beds and coral reefs. The time since drilling ranged from 2 to 29 years; water depths varied between 5 and 70 m. The major long-term ecological impact observed at these sites ranged from the creation of "artificial-reef" conditions to the physical destruction of hardbottom habitat that had not recovered in 29 years. Long-term ecological perturbation appeared to be limited to physical destruction and the deposition of drilling debris, which provided substratum for settling organisms. Significant deposits of drill muds or cuttings were not encountered at any of the sites, and there was no evidence of ecological damage from cuttings or drill muds. The results of this study pertain only to exploratory drilling that, unlike production wells that remain in place for tens of years, is a one-time perturbation to the habitat.

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USGS1990

Radium and radon in Charlotte Harbor Estuary, Florida

Radium-226 and 222 Rn activities are greater in the estuarine waters of northern Charlotte Harbor and the lower tidal Peace and Myakka Rivers, Florida, than in either the freshwater reaches of the rivers or waters of the lower estuary and the Gulf of Mexico. The activity of 226 Ra in the tidal rivers increases with decreasing river inflow, with a maximum value of 548 dpm 1001 −1 measured in the tidal Myakka River. The source of the high activity of 226 Ra and 222 Rn is predominantly ground water inflow. Because of the large ground water input, the contribution of 226 Ra from suspended and bottom sediments is a smaller fraction of the total 226 Ra input than in many other estuaries. Although ground water 226 Ra activity in the area varies widely, we estimate that artesian ground water inflow to the tidal rivers is similar in magnitude to the flow of the rivers above the tidal reach during the dry season.

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USGS1990

Simulation of cotton rat population dynamics and response to rodenticide applications in Florida sugarcane

Alternative deterministic simulation models were compared to test the management consequences of present uncertainty about the degree of density dependence involved in cotton rat population cycles in southern Florida sugarcane fields. Efficacy of rodenticide applied in different months was explored under six different scenarios of density dependence and independence in two population parameters: fecundity and juvenile survival. Output from the six models differed considerably in the number of rats produced, but was remarkably consistent in the most effective months to apply rodenticide. Since models without density-dependent fecundity were inherently unstable and an inverse relationship between fecundity and population size is apparent in field data, such a population-growth mechanism seems possible in Florida sugarcane fields. The model in which fecundity was density-dependent at all times produced rat densities closest to field data. Output from this model was most sensitive to changes in the amount litter size declines as population size increases. Field tests are necessary to validate the general agreement among the models about the most effective months to apply rodenticide.

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