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Research about Florida

Source-linked reports with geographic coverage including Florida.

At least 1,549 records · Page 86Linked to original sources
USGS1994

Water resources data, Florida, water year 1993. Volume 2B: South Florida - ground water

Water resources data for 1993 water year in Florida consists of continuous or daily discharge for 312 streams, periodic discharge for 9 streams, miscellaneous discharge for 107 streams, continuous or daily stage for 91 streams, periodic stage for 0 streams, peak discharge for 30 streams, continuous daily tide stage for 9 streams, and peak stage for 21 streams, continuous or daily elevations for 41 lakes, periodic elevations for 73 lakes; continuous ground-water levels for 406 wells, periodic ground-water levels for 569 wells, and miscellaneous water level measurements for 1,860 wells; quality of water data for 109 surface-water sites and 642 wells. The data for South Florida included continuous or daily discharge for 75 streams, continuous or daily stage for 54 streams, peak stage discharge for 1 stream, continuous elevation for 1 lake; continuous ground-water levels for 203 wells, periodic ground-water levels for 299 wells and miscellaneous water-level measurements for 462 wells; quality-of-water for 3 surface-water sites and 545 wells. The 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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USGS1994

Water resources data, Florida, water year 1993; Volume 3A. Southwest Florida surface water

The Water Resources Division of the U.S. Geological Survey, in cooperation with local, State, and Federal agencies, obtains a large amount of data pertaining to the water resources of Florida each water year. These data, accumulated during many water years, constitute a valuable data base for developing an improved understanding of the water resources of the State. To make these data readily available to interested parties outside the Geological Survey, the data are published annually in this report series entitled "Water Resources Data - Florida."

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USGS1994

Water resources data, Florida, water year 1993. Volume 3B: Southwest Florida - ground water

Water resources data for the 1993 water year in Florida consist of continuous or daily discharges for 312 streams, periodic discharge for 9 streams, miscellaneous discharge for 107 streams, continuous or daily stage for 91 streams, continuous daily tide stage for 9 sites, periodic stage for 0 streams, peak discharge for 30 streams, and peak stage for 30 streams; continuous or daily elevations for 41 lakes, periodic elevations for 73 lakes; continuous ground-water levels for 406 wells, periodic ground-water levels for 569 wells, and miscellaneous water level measurements for 1860 wells; quality-of-water data for 109 surface-water sites and 642 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 141 wells; periodic ground-water elevations at 100 wells; miscellaneous ground-water elevations at 395 wells; and water quality at 28 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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USGS1994

Water resources data, Florida, water year 1994; Volume 1B. Northeast Florida ground water

The Water Resources Division of the U.S. Geological Survey, in cooperation with State, local, and Federal agencies, obtains a large amount of data pertaining to the water resources of Florida each water year. These data, accumulated during many water years, constitute a valuable data base for developing an improved understanding of the water resources of the State.

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USGS1994

Water resources data, Florida, water year 1999. Volume 3A: Southwest Florida - surface water

Water resources data for the 1999 water year in Florida consist of continuous or daily discharges for 354 streams, periodic discharge for 17 streams, continuous or daily stage for 121 streams, periodic stage for 1 stream, peak stage and discharge for 38 streams, continuous or daily elevations for 21 lakes, periodic elevations for 42 lakes; continuous ground-water levels for 408 wells, periodic ground-water levels for 1,715 wells, and quality-of-water data for 131 surface-water sites and 198 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 82 streams, periodic discharge for 13 streams, continuous or daily stage for 39 streams, peak stage and discharge for 7 streams, continuous or daily elevations for 6 lakes, periodic elevations for 25 lakes, and quality-of-water data for 75 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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USGS1994

Saltwater intrusion and quality of water in the Floridan aquifer system, northeastern Florida

Saltwater intrusion into freshwater aquifers has resulted in increased chloride concentrations in water from some wells in northeastern Florida. The principal areas of saltwater intrusion in the Floridan aquifer system in the study area are east-central Duval County, the southern two-thirds of St. Johns County, and along the coast. At least five possible mechanisms of saltwater movement, some more plausible than others, could explain the observed increases in chloride concentration in the upper freshwater zones of the Floridan aquifer. They are (1) the presence of unflushed pockets of relict seawater; (2) lateral movement of the freshwater-saltwater interface off the northeastern Florida coast; (3) upconing of saltwater from deeper, salty zones below pumped wells; (4) upward leakage from deeper, salty water-bearing zones through failed, uncased, or improperly plugged or constructed wells; and (5) upward leakage from salty water-bearing zones through semiconfining units that are thin, or are breached by joints, faults, or collapse features. Ground-water withdrawals in Duval, Nassau, and St. Johns Counties increased from about 183 to 254 million gallons per day from 1965 to 1988. Approximately 90 percent of the total withdrawal is from the Floridan aquifer system, resulting in long-term declines in the potentiometric surface of the Upper Floridan aquifer of about one-third to three-fourths foot per year. Hydraulic heads in the lower part of the aquifer system are naturally higher than in the upper parts. Declines in head in the upper part have further increased the vertical head difference between zones, increasing the potential for vertical ground-water flow from lower zones of higher head upward through structural deformities, leaky confining beds, and wells, to higher zones of lower head. Lower zones typically have higher chloride concentrations than do upper zones. Concentrations of chemical constituents in water from the Floridan aquifer system vary both areally and with depth. Chloride concentrations in water in the Upper Floridan aquifer in the study area range from about 4.6 to 3,600 milligrams per liter. Data indicate that in much of the study area, water in the upper zone of the Lower Floridan aquifer generally is slightly more mineralized than water from the overlying Upper Floridan aquifer. Water from the Fernandina permeable zone varies in quality from fresh to saline. Chemical analyses of water from five monitoring wells tapping this zone indicate maximum chloride concentrations of 16,800 milligrams per liter. The potential for saltwater contamination of the freshwater-bearing zones probably will continue to increase in northeastern Florida as artesian pressure in the upper freshwater zones continues to decline. Implementation of wise water-management strategies could, however, reduce the potential for saltwater intrusion.

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USGS1994

Quality of water and bottom sediments, and nutrient and dissolved-solids loads in the Apopka-Beauclair Canal, Lake County, Florida, 1986-90

Nutrient-rich water enters Lake Beauclair and other lakes downstream from Lake Apopka in the Ocklawaha River chain of lakes in central Florida. Two sources of the nutrient-rich water are Lake Apopka outflow and drainage from farming operations adjacent to the Apopka-Beauclair Canal. Two flow and water- quality monitoring sites were established to measure nutrient and dissolved-solids loads at the outflow from lake Apopka and at a control structure on the Apopka-Beauclair Canal downstream from farming activities. Samples were collected biweekly for analysis of nutrients and monthly for analysis of major ions for 4 years. Most of the nutrient load transported through the lock and dam on the Apopka-Beauclair Canal was transported during periods of high discharge. In April 1987, when discharges were as high as 589 cubic feet per second, loads transported through the lock and dam accounted for 59 percent of the ammonia-plus- organic nitrogen load, 61 percent of the total nitrogen load, and 59 percent of the phosphorus load transported during the 1987 water year. Constituent concentrations in annual bottom sediment samples from the canal indicated that most of the constituent load is not being transported down- stream. An alternative approach was derived for determining the relative constituent load from farm input along the canal: Load computations using this approach indicated that, with the exception of phosphorus, nutrient and dissolved-solids loads due to farm activity along the canal account for 10 percent or less of the total load at the Apopka-Beauclair canal lock and dam.

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USGS1994

Water resources of Duval County, Florida

The report describes the hydrology and water resources of Duval County, the development of its water supplies, and water use within the county. Also included are descriptions of various natural features of the county (such as topography and geology), an explanation of the hydrologic cycle, and an interpretation of the relationship between them. Ground-water and surface-water resources and principal water-quality features within the county are also discussed. The report is intended to provide the general public with an overview of the water resources Of Duval County, and to increase public awareness of water issues. Information is presented in nontechnical language to enable the general reader to understand facts about water as a part of nature, and the problems associated with its development and use.

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USGS1994

Ground-water quality and trends at two industrial wastewater-injection sites in northwestern Florida, 1975-91

Industrial wastewater from two synthetic-fiber manufacturing plants has been injected into the Lower Floridan aquifer near Pensacola, Florida, since 1963, and near Milton, Florida, since 1975. Trend analysis of selected water-quality characteristics in water from four monitoring wells at each of these plants indicates that injected wastewater has affected ground-water quality in the Lower Floridan aquifer, which contains nonpotable water, up to 1.5 miles from the injection wells at the plant near Pensacola and at least 0.3 mile from the injection wells at the plant near Milton. No evidence for upward seepage of injected wastewater through the overlying Bucatunna Clay to the Upper Floridan aquifer was found at either of the plants.

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USGS1994

Hydrogeology and the distribution and origin of salinity in the Floridan aquifer system, southeastern Florida

The Floridan aquifer system in southeastern Florida consists of the Upper Floridan aquifer, the middle confining unit, and the Lower Floridan aquifer. An upper zone of brackish water and a lower zone of water with a salinity similar to that of seawater are present in the Floridan aquifer system. The brackish-water zone is defined as that in which water has a dissolved-solids concentration of less than 10,000 milligrams per liter (chloride concentration less than about 5,240 milligrams per liter), and water in the the saline-water zone has a dissolved solids concentration of about 35,000 milligrams per liter (about 18,900 milligrams per liter chloride concentration). The brackish-water and saline-water zones are separated by a transitional zone, typically 100 feet thick, in which salinity increases abruptly with depth. The base of the brackish-water zone lies within the Upper Floridan aquifer along the coast but extends into the middle confining unit inland. The brackish- water zone is as much as 1,200 feet thick inland, whereas the Upper Floridart aquifer is typically 500 to 600 feet thick. Changes in lithology or permeability do not usually control the position of the boundary between the brackish-water and saline-water zones. Calculations of the depth of a brackish-water and saline-water interface using the Ghyben-Herzberg relation show good agreement between calculated and actual positions of the interface, indicating equilibrium between the zones. Several areas of high salinity with chloride concentrations greater than 3,000 milligrams per liter are present in the upper interval of the brackish-water zone near the coast, and in one of these areas in northeastern Broward County, salinity decreases with depth from the upper to lower interval. The high salinities could be a result of seawater preferentially encroaching into zones of higher permeability in the Upper Flofidan aquifer during Pleistocene high stands of sea level and incomplete flushing of the seawater by the present-day flow system.

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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.

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USGS1994

Nitrate in ground water and spring water near four dairy farms in North Florida, 1990-93

Concentrations of nitrate and other selected water- quality characteristics were analyzed periodically for two years in water from 51 monitoring wells installed at four farms and in water discharging from three nearby springs along the Suwannee River in Lafayette and Suwannee Counties to examine the quality of ground water at these farms and the transport of nutrients in ground water to the nearby spring-fed Suwannee River: Ground water from shallow wells, which were completed in the top ten feet of the saturated zone in a surficial sandy aquifer and in the karstic Upper Floridan aquifer generally had the highest concentrations of nitrate, ranging from <.02 to 130 mg/L as nitrogen. Nitrate concentrations commonly exceeded the primary drinking water standard of 10 mg/L for nitrate as nitrogen in water from shallow wells, which tapped the top ten feet of the uppermost aquifers near waste-disposal areas such as wastewater lagoons and defoliated, intensive-use areas near milking barns. Upgradient from waste-disposal areas, concentrations of nitrate in ground water were commonly less than 1 mg/L as nitrogen. Water samples from deep wells (screened 20 feet deeper than shallow wells in these aquifers) generally had lower concentrations of nitrate (ranging from <0.02 to 84 mg/L) than water from shallow wells. Water samples from the three monitored springs (Blue, Telford, and Convict Springs) had nitrate concentrations ranging from 1.5 to 6.5 mg/L as nitrogen, which were higher than those typically occurring in water from upgradient wells at the monitored dairy farms or from back- ground wells sampled in the region. Analyses of nitrogen isotope ratios in nitrate indicated that leachate from animal wastes was the principal source of nitrate in ground water adjacent to waste-disposal areas at the monitored and unmonitored dairy farms. Leachate from a combi- nation of fertilizers, soils, and animal wastes appeared to be the source of nitrate in ground- water downgradient from pastures and wastewater spray fields at dairy farms and in water discharging from three nearby springs. Although denitrifying bacteria were present in counts sometimes exceeding 240,000 colonies/100mL in water from dairy-farm monitoring wells, ground water in the uppermost aquifers in Lafayette and Suwannee Counties generally contained too much oxygen for denitrification to remove nitrate from shallow ground water. Denitrification was more likely to occur in deeper ground water, which typically has lower dissolved oxygen concentrations.

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USGS1994

Environmental implications of growth rate changes in Montastrea Annularis : Biscayne National Park, Florida

Long-term annual growth rates were determined for 25 Montastrea annularis colonies at eight reef sites in Biscayne National Park, Florida. X-radiographs of slabbed coral cores revealed chronologies that averaged 113.5 years in length with a range of 40 to 242 years. A total of 2,837 annual growth increments were identified and measured. Dating of density bands was verified by visually crossdating fluorescent bands within the coral skeleton. Average accretion rates of individual colonies varied from 5.0 mm&middot;yr &minus;1 in the northernmost sector of the Park to 11.3 mm&middot;yr &minus;1 in the southernmost sector. Long-term growth rates of most corals in this study were greatest prior to about 1950 except for a major, 3&ndash;5 year, decline in the growth record of older corals centered around 1878. Waxing and waning coral growth rates are discussed in relation to natural and anthropogenic perturbations that impact this high latitude reef ecosystem. Attention is drawn to nutrients from sewage outfalls as a possible contributing factor to observed growth rate decline since 1950.

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USGS1993

Lime-mud layers in high-energy tidal channels: A record of hurricane deposition

During or immediately following the transit of Hurricane Andrew (August 23-24, 1992) across the northern part of the Great Bahama Bank, thin laminated beds of carbonate mud were deposited in high-energy subtidal channels (4 m depth) through the ooid shoals of south Cat Cay and Joulters Cays. During our reconnaissance seven weeks later, we observed lime-mud beds exposed in the troughs of submarine oolite dunes and ripples. The mud layers were underlain and locally covered by ooid sand. The mud beds were lenticular and up to 5 cm thick. Their bases cast the underlying rippled surface. The layers were composed of soft silt- and sand-sized pellets and peloids and in some areas contained freshly preserved Thalassia blades and other organic debris along planes of lamination. The beds had a gelatinous consistency and locally had been penetrated by burrowers and plants. Layers of lime mud had also settled on bioturbated, plant-stabilized flats and in lagoonal settings but were quickly reworked and made unrecognizable by the burrowing of organisms. Thicker, more cohesive (and therefore older) mud beds and angular mud fragments associated with ooids from Joulters Cays have similar characteristics but lack fresh plant fragments. We infer that these older beds were similarly deposited and thus record the passage of previous hurricanes or tropical storms. Storm layers are preserved within channel sediments because migrating ooids prevent attack by the burrowing activity off organisms.

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