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Bradley G. Waller

Publications and source records attributed to Bradley G. Waller.

12 recordsLinked to original sources
USGS1986

Water-quality data for the ground-water network in eastern Broward County, Florida, 1983-84

During 1983-84, ground water from 63 wells located at 31 sites throughout, eastern Broward County, Florida, was sampled and analyzed to determine baseline water-quality conditions. The physical and chemical parameters analyzed included field measurements (pH and temperature), physical characteristics (color, turbidity, and specific conductance), major inorganic ions, nutrients (nitrogen, phosphorus, and carbon), selected trace metals, and total phenolic compounds. Ground-water samples were collected at the end of the dry season (April), during rising water levels (June and July), and during yearly peak water levels (September and October). These data are tabulated, by well, in this report.

Florida↗
USGS1986

FLOOD REDUCTION EFFICIENCY OF THE WATER-MANAGEMENT SYSTEM IN DADE COUNTY (MIAMI), FLORIDA.

Two tropical weather systems, Hurricane Donna (1960) and Tropical Storm Dennis (1981), produced nearly equivalent amounts of rainfall in a 48-hour period south of the Miami (Florida) area. These two systems caused extensive flooding over a 600-square mile area, which is primarily agricultural and low density residential. The 1960 and 1981 storms caused the highest water levels recorded in south Dade County since flood-control measures were initiated for south Florida in 1949. Ground-water levels during both storms rose 4 to 8 feet over most of the area causing widespread inundation. Operation of the water-management system in 1981 provided flood protection and rapid recession of ground-water levels thereby minimizing damage.

Conference Paper↗
USGS1985

Synopsis of saltwater intrusion in Dade County, Florida, through 1984

The inland position of saltwater at the base of the highly permeable limestone of the Biscayne aquifer in Dade County in 1984 is a consequence of: (1) years of adjustment to lowered water levels resulting from regional drainage for flood control and land reclamation; (2) increased freshwater withdrawals; and (3) water-control and water-management practices implemented at the south part of the hydrologic system as well as in upgradient areas. As water demands in southeast Florida continue to increase, further intrusion could be related to increased pumping from well fields. Implementation of additional management practices to further reduce canal discharge to the ocean would tend to sustain water levels high enough to retard intrusion during dry seasons. (USGS)

Water-Resources Investigations Report↗
USGS1984

Attenuation of stormwater contaminants from highway runoff within unsaturated limestone, Dade County, Florida

Infiltration of stormwater in heavily urbanized parts of Dade County, Florida, is a prime source of recharge to the unconfined Biscayne aquifer, the sole source of drinking water for southeast Florida. Ponded stormwater at the test site contained greater concentrations of lead, zinc, manganese, nitrogen (except nitrate), and phosphorus than the water which percolated through the unsaturated limestone. Attenuation of some stormwater contaminants in the surface soils and limestone is indicated at the test site adjacent to a busy throughfare. Lead concentrations of 610 micrograms per kilogram and zinc concentrations of 91 micrograms per kilogram were found in the thin surface soils, nearly 20 times more than the concentrations of these metals at greater depth. In contrast, soil and rock sample at a control site remote from heavy traffic contained low concentrations of metals and showed little variation in concentration with depth. (USGS)

Florida↗
USGS1982

Effects of land use on surface-water quality in the East Everglades, Dade County, Florida

Water-quality characteristics were determined at five developed areas in the East Everglades, Dade County, Florida, during the 1978 wet season (June through October). These areas are designated as: Coopertown; Chekika Hammock State Park; residential area; rock-plowed tomato field; and Cracker Jack Slough agricultural area. Data from the developed areas were compared with data from four baseline sites in undeveloped areas to determine the effects of land use on the surface-water quality. The rock-plowed tomato field was the only area where surface-water quality was affected. Water quality at this field is affected by agricultural activities and chemical applications as indicated by increased concentrations of orthophosphate, organic nitrogen, organic carbon, copper, manganese, mercury, and potassium. The remaining four areas of land use had water-quality characteristics typical of baseline sites in nearby Northeast Shark River Slough or Taylor Slough. Chemical analyses of soil indicated chlorinated-hydrocarbon insecticide residues at Coopertown and the two agricultural areas, Cracker Jack Slough and the rock-plowed tomato field. Trace elements in concentrations greater than base level occurred at both agricultural areas (manganese), Chekika Hammock State Park (manganese), and at Coopertown (lead and zinc). (USGS)

Florida↗
USGS1982

Areal extent of a plume of mineralized water from a flowing artesian well in Dade County, Florida

A flowing artesian well that taps the Floridan aquifer at Chekika Hammock State Park is contaminating the overlying Biscayne aquifer with saline water. The plume of mineralized water extends approximately 7 miles southeast of the well and ranges in width from 1 to 2 miles. The areal extent of contamination in the primary plume is approximately 12 square miles. The principal ions contaminating the Biscayne aquifer are chloride, sodium, and sulfate. (USGS)

Florida↗
USGS1982

Assessment of water quality in canals of eastern Broward County, Florida, 1969-74

An intensive water-quality monitoring program was started in 1969 to determine the effects of man-induced contaminants on the water quality in the primary canal system of eastern Broward County, Florida. This report covers the first 6 years of the program and provides a data base that can be used to compare future changes in water-quality conditions. Most data indicate that beyond the small seasonal fluctuation in constituent level, the greatest adverse effect on the quality of water is caused by discharge of sewage and treated sewage effluent to the canals. The areas affected by sewage have greater concentrations of macronutrients, trace metals, and pesticides than unaffected areas. Major-ion concentrations were affected only by season and local lithology. Over the 6-year study a gradual decrease in macronutrient concentration and an increase in dissolved oxygen have occurred. This improvement in water quality is attributed to a decrease of sewage discharge into canals and better treatment of sewage effluents. (USGS)

Florida↗
USGS1981

Water-quality data for selected stations in the East Everglades, Florida

The results of water-quality samples collected from April 1978 through April 1980 from three canal stations, four marsh stations, and two ground-water stations within the East Everglades, Dade County, Florida, are tabulated in 37 tables. The major categories of parameters analyzed are field measurements, physical characteristics, macronutrients (carbon, nitrogen, and phosphorus), major ions, trace elements, and algae. Chemical data for bulk-precipitation stations within and adjacent to the East Everglades are also given. The parameters analyzed include macronutrients, major ions, and trace elements. The period of record for these stations is October 1977 through April 1980. Bottom material at the canal and marsh stations was collected twice during the investigation. These data include analyses for macronutrients, trace elements, and chlorinated-hydrocarbon insecticides.

Florida↗
USGS1976

Analysis of selected benthic communities in Florida Everglades with reference to their physical and chemical environment

Species diversity and numbers of benthic macroinvertebrates were determined at 12 sites, both canals and marshes, in the Everglades of south Florida. The values calculated are used to indicate long-term trends in water quality and variations between study areas. Species diversity at all sites was generally in a range indicative of degraded water quality. The number of organisms per square metre of bottom surface was highly variable ranging from 43 to 8,200 organisms. Chemical analysis of water and bottom material indicated no gross contamination from sewage or agricultural runoff in any of the canals where benthic organisms were collected. Other physical factors such as depth, velocity of flow, substrate type, and water-level fluctuation were responsible for the low species diversities and variable numbers of organisms, rather than contamination from urban or agricultural areas.

Florida↗
USGS1976

Nitrogen and phosphorus uptake in the Everglades Conservation Areas, Florida, with special reference to the effects of backpumping runoff

In much of the water pumped into the northern Everglades, Florida, concentrations of inorganic nitrogen and phosphorus are relatively high. These nutrients are transported in the canals or into the peripheral marshes. Concentrations decrease sharply within 330 feet or less of the canals, whereas specific conductance remains essentially unchanged within this distance. The sharp decrease in inorganic nitrogen and phosphorus near the canal edge indicates net uptake in these shallow waters. Concentrations of nitrogen and phosphorus also decrease as water moves through the conservation areas in canals. This decrease is due partly to dilution by rainfall and runoff, and partly to net uptake in the canals and their peripheral marsh. The large canals of the northern and eastern parts of the conservation areas often have relatively low concentrations of dissolved oxygen which show little fluctuation within 24 hours. Backpumping 50 percent of the total annual canal runoff in southeast Florida would add from 990 to 6,160 tons of nitrogen and from 10 to 62 tons of phosphorus to the conservation areas. The bottom sediments of the Everglades are a sink for nitrogen and phosphorus. They can, however, be a source of these nutrients when anaerobic conditions exist at the water-sediment interface or when bottom material becomes resuspended. (Woodard-USGS)

Florida↗
USGS1975

Chemical and biological quality of water in part of the Everglades, southeastern Florida

A comprehensive monitoring network was established in a part of the Everglades to evaluate the quality of water being delivered to Everglades National Park. Physical, chemical, and biological parameters were determined in surface water, bottom sediment, and bulk precipitation (rainfall and dry fallout). The geology of the area, bottom sediment, bulk precipitation, natural, urban, and agricultural runoff, and the characteristics of the hydrologic system in the Everglades influence the type and concentration of each chemical constituent and how it affects the water quality. The quality of surface water in the agricultural area between Lake Okeechobee and the water conservation areas is markedly different from that of other surface water in southeastern Florida. In general, the water in this area is higher in concentrations of most chemical constituents. Man has engaged in cultural activities, both agricultural and urban, which have affected the water quality in the northern and eastern segments of the area of investigation. The quality of the water improves, however, as it flows to the south and east because there is minimal input from man's activities and many of the constituents are assimilated by plants, sorbed on organic material and clay in the bottom sediments, and entrapped within the sediments. Dilution by rainfall and concentration by evapotranspiration are also important factors that influence the quality of surface water in the area of investigation. The area of investigation in the Everglades is a sink for macronutrients, trace metals, and chlorinated-hydrocarbon insecticides. These constituents do not move through the system freely. They become tied up in various complexes and for that reason, the water being delivered to Everglades National Park is of better quality than the water entering the northern edge of the water conservation areas. The various physical and biological processes and chemical reactions combine to improve the water quality as the water flows southward. The data presented in this report may be used as a baseline for determination of future changes in water quality at the several places in the Everglades where recurrent sampling of rainfall, surface water, and bottom sediments was undertaken during the course of the investigation.

Florida↗