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Benjamin F. McPherson

Publications and source records attributed to Benjamin F. McPherson.

At least 19 recordsLinked to original sources

Water quality in the Arthur R. Marshall Loxahatchee National Wildlife Refuge — Trends and spatial characteristics of selected constituents, 1974-2004

Water quality in the interior marsh of the Arthur R. Marshall Loxahatchee National Wildlife Refuge is characterized by low concentrations of major ions, principally sodium and chloride, and is affected primarily by natural seasonal processes, such as evapotranspiration, rainfall, and biological activity. During the dry season, evapotranspiration exceeds precipitation, and specific conductance and conservative ion concentrations at marsh background sites typically increase by 40-70 percent between the end of the rainy season in September and the end of the dry season in May. Water enters the Refuge mainly from rainfall and perimeter canals. Water is pumped into the perimeter canals from large pumping stations, such as S-5A and S-6. In recent years, much of the water pumped into the Refuge passes through Stormwater Treatment Areas (STAs) before being released into the perimeter canals that surround the Refuge. Since 2001, water at S-6 has been diverted south toward STA-2, away from the Refuge perimeter canals. Water from S-5A and S-6 flows through agricultural lands with intense agricultural activity and typically contains relatively high concentrations of major ions, nutrients, and pesticides. Specific conductance, major-ion concentrations, and nutrient concentrations are an order of magnitude higher at S-5A and S-6 canal sites than at interior marsh sites. Water quality in the marsh bordering the canals can be affected substantially by the canal water, and these effects can extend several miles or more into the marsh depending on location in the Refuge and on the water level in the canals. As canal water flows into the marsh, processes such as uptake by periphyton and rooted vegetation and settling of particulate matter reduce the concentrations of nutrients to a greater extent than conservative ions such as chloride. Long- and short-term trends for specific conductance, chloride ion, sulfate ion, total phosphorus, and total nitrogen at five sites were evaluated primarily using an uncensored seasonal Kendall test with a water-level adjustment to reduce the effects of long wet or dry periods. Significant long-term trends (1974-2003) for specific conductance, chloride, total phosphorus, and total nitrogen at canal sites S-5A and S-6 were generally downward. Of the five sites, S-5A had the most pronounced decline for specific conductance at about -340 microsiemens per centimeter (?S/cm), followed by S-6 with a decline of about -280 ?S/cm. The two internal marsh sites, LOX8 and LOX13, had significant long-term trends in specific conductance of about +37 and -36 ?S/cm, respectively. Long-term trends for other constituents at the two internal marsh sites were generally small in magnitude or not measurable between 1978 and 2003. Marsh site LOX15 near the Hillsboro Canal showed no long-term trends, although specific conductance and sulfate concentration increased about 560 ?S/cm and 30 milligrams per liter, respectively, from 1998 to 2002. Site LOX15 is influenced strongly by intrusions of canal water, and increases in specific conductance and sulfate at this site coincided with increased canal-water inflows from STA-1W between 2001 and 2003. Median concentrations at LOX13 and S-5A were used to represent background and canal concentrations, respectively. Based on these values, the median chloride concentration at LOX15 indicates that the water is typically about 31 percent canal water and 69 percent ?natural? background water. Using median sulfate concentrations, similarly to chloride, the fraction of water at LOX15 was estimated to be 17 percent from canals and 83 percent from ?natural? background water. This finding suggests that in the low sulfate environment of the Refuge, sulfate is not conservative and only about half of the sulfate from canal water typically reaches LOX15; the rest presumably is removed by marsh plants, algae, and bottom sediments. Concentrations of pesticides and other organic compounds were measured

Florida

Assessment of groundwater input and water quality changes impacting natural vegetation in the Loxahatchee River and floodplain ecosystem, Florida

The Loxahatchee River and Estuary are small, shallow, water bodies located in southeastern Florida. Historically, the Northwest Branch (Fork) of the Loxahatchee River was primarily a freshwater system. In 1947, the river inlet at Jupiter was dredged for navigation and has remained permanently open since that time. Drainage patterns within the basin have also been altered significantly due to land development, road construction (e.g., Florida Turnpike), and construction of the C-18 and other canals. These anthropogenic activities along with sea level rise have resulted in significant adverse impacts on the ecosystem over the last several decades, including increased saltwater encroachment and undesired vegetation changes in the floodplain. The problem of saltwater intrusion and vegetation degradation in the Loxahatchee River may be partly induced by diminished freshwater input, from both surface water and ground water into the River system. The overall objective of this project was to assess the seasonal surface water and groundwater interaction and the influence of the biogeochemical characteristics of shallow groundwater and porewater on vegetation health in the Loxahatchee floodplain. The hypothesis tested are: (1) groundwater influx constitutes a significant component of the overall flow of water into the Loxahatchee River; (2) salinity and other chemical constituents in shallow groundwater and porewater of the river floodplain may affect the distribution and health of the floodplain vegetation.

Florida

Freshwater and Nutrient Fluxes to Coastal Waters of Everglades National Park - A Synthesis

Freshwater in the Everglades and the Big Cypress Swamp drains south and southwest into coastal regions where it mixes with seawater to create the salinity gradients characteristic of productive estuarine and marine systems. Studies in Florida Bay have shown that over the last 100-200 years, salinity and seagrass distributions have fluctuated substantially in response to natural climatic cycles. The timing of this change coincides at least in part with the canal construction and landscape alterations in the Everglades that have altered the quantity, timing, distribution, and quality of surface water that flows south into the coastal waters. Federal and State agencies have undertaken a massive Everglades restoration project that will require changes in water management throughout the Everglades, and this will affect water flows to the coastal region. A major concern involves how changes in water flow could affect salinity and nutrient availability in coastal waters.

Fact Sheet

Quality of ground water in the Biscayne Aquifer in Miami-Dade, Broward, and Palm Beach counties, Florida, 1996-1998, with emphasis on contaminants

The high permeability of the sand and limestone sediments and shallow water table of the Biscayne aquifer make ground water vulnerable to contamination by human activities. To assess potential contamination in the aquifer, untreated ground water was sampled from 30 public-supply wells (40-165 feet deep) in Broward, Miami-Dade, and Palm Beach Counties, 32 shallow wells (10-50 feet deep) in a recently urbanized (residential and light commercial) part of Broward County, and 3 shallow reference wells in Broward County. Results from sample analyses indicate that major ions, pH, dissolved oxygen, nutrients, and trace element concentrations were generally within the range indicative of background concentrations, except for: (1) substantially higher bromide concentrations in water from public-supply wells in southern Miami-Dade County; (2) a few relatively high (greater than 2 milligrams per liter) concentrations of nitrate in water from public-supply wells near agricultural lands in Miami-Dade and southern Broward Counties; and (3) a few relatively high concentrations of arsenic (greater than 10 micrograms per liter) in water from some shallow urban wells near golf courses. Pesticides were detected in every public-supply well, in most of the shallow, urban monitoring wells (78 percent), and in one reference well; however, no pesticide concentration exceeded any drinking-water standard. Fifteen different pesticides or their degradation products were detected. The most frequently detected pesticides were atrazine and tebuthiuron; less frequently detected were the herbicides diuron, fenuron, prometon, metolachlor, simazine, and 2,6-diethylaniline. Volatile organic compounds (VOCs) were detected in most of the public-supply wells (77 percent) and shallow, urban wells (91 percent) and in two of the three reference wells. Thirty-two different VOCs were detected in ground water in the Biscayne aquifer, with cis-1,2-dichloroethene the most frequently detected VOC in the public-supply wells, followed by methyl tert-butyl ether (MTBE), 1,4-dichlorobenzene, and chloroform. Toluene, p-isopropyltoluene, and 1,2,4-trimethylbenzene were the most frequently detected VOCs in the shallow, urban wells. Concentrations of all VOCs were less than the maximum contaminant level (MCL) for public drinking water, except in two samples from public-supply wells near industrialized areas that had vinyl chloride concentrations (3 and 5 micrograms per liter) above the MCL of 1 microgram per liter.

Open-File Report

Water quality in Big Cypress National Preserve and Everglades National Park — Trends and spatial characteristics of selected constituents

Seasonal changes in water levels and flows in Big Cypress National Preserve (BICY) and Everglades National Park (EVER) affect water quality. As water levels and flows decline during the dry season, physical, geochemical and biological processes increase the breakdown of organic materials and the build-up of organic waste, nutrients, and other constituents in the remaining surface water. For example, concentrations of total phosphorus in the marsh are less than 0.01 milligram per liter (mg/L) during much of the year. Concentrations can rise briefly above this value during the dry season and occasionally exceed 0.1 mg/L under drought conditions. Long-term changes in water levels, flows, water management, and upstream land use also affect water quality in BICY and EVER, based on analysis of available data (1959-2000). During the 1980's and early 1990's, specific conductance and concentrations of chloride increased in the Taylor Slough and Shark River Slough. Chloride concentrations more than doubled from 1960 to 1990, primarily due to greater canal transport of high dissolved solids into the sloughs. Some apparent long-term trends in sulfate and total phosphorus were likely attributable, at least in part, to high percentages of less-than and zero values and to changes in reporting levels over the period of record. High values in nutrient concentrations were evident during dry periods of the 1980's and were attributable either to increased canal inflows of nutrient-rich water, increased nutrient releases from breakdown of organic bottom sediment, or increased build-up of nutrient waste from concentrations of aquatic biota and wildlife in remaining ponds. Long-term changes in water quality over the period of record are less pronounced in the western Everglades and the Big Cypress Swamp; however, short-term seasonal and drought-related changes are evident. Water quality varies spatially across the region because of natural variations in geology, hydrology, and vegetation and because of differences in water management and land use. Nutrient concentrations are relatively low in BICY and EVER compared with concentrations in parts of the northern Everglades that are near agricultural and urban lands. Concentrations of total phosphorus generally are higher in BICY (median values, 1991-2000, were mostly greater than 0.015 mg/L) than in EVER (median values, 1991-2000, less than 0.01 mg/L), probably because of higher phosphorus in natural sources such as shallow soils, rocks, and ground water in the Big Cypress region than in the Everglades region. Conversely, concentrations of chloride and sulfate are higher in EVER (median values in Shark River Slough, 1991-2000, mostly greater than 2 mg/L sulfate and 50 mg/L chloride) than in BICY (median values, 1991-2000, less than 1 mg/L sulfate and at most sites less than 20 mg/L chloride), probably because of the canal transport system, which conveys more water from an agricultural source into EVER than into BICY. Trace elements and contaminants such as pesticides and other toxic organic compounds are in relatively low concentrations in BICY and EVER compared with concentrations in parts of the northern Everglades near agricultural and urban sources. Concentrations rarely exceeded aquatic life criteria in BICY and EVER. Atrazine was the only pesticide found in water that exceeded the criteria (in 2 out of 304 samples). The pesticides heptachlor expoxide, lindane, and p,p?-DDE exceeded criteria in canal bed sediments in 1, 2, and 16 percent of the samples, respectively.

Florida

Science Plan, U.S. Geological Survey Florida District

This Science Plan has been prepared by the Florida District of the U.S. Geological Survey (USGS) as a tool to provide direction for the scientific work to be accomplished in the District during the next 5-10 years. A Science Plan can serve as a guide to determine the optimum use of the limited financial resources of the USGS in Florida to address water resource issues. The Florida District has four primary operational centers geographically distributed across the State, in Tallahassee, Orlando, Tampa, and Miami, with a laboratory in Ocala and field offices in Jacksonville and Fort Myers. Other USGS discipline offices in Florida are located in Gainesville (biology), St. Petersburg (geology), and Miami (restoration ecology) (fig.1). Although some differences exist in programs among the four water-resource offices because of differing physiographic settings and information needs, many common elements are present and these common elements are the focus of this District Science Plan. Science Plan development was based on other planning documents including individual Science Plans prepared by personnel in each of the four primary Florida water resource offices, and strategic planning documents of the Southeastern Region, Water Resources Discipline (WRD), and the USGS. A broad cross-section of District staff, representing all primary offices, a number of different scientific disciplines, and different programs of the District (data collection, investigations, and research) collaborated on the development of this Science Plan. As part of the development process, input was solicited from staff in every office and considered for inclusion in the plan. The Science Plan will be evaluated on an ongoing basis to ensure its continued relevancy to recognized water resources needs in Florida, and to guide future program development and collaboration with our existing and potential partners and customers, both within and outside the USGS.

Florida

Occurrence and distribution of contaminants in bottom sediment and water of the Barron River Canal, Big Cypress National Preserve, Florida

Trace elements and organic contaminants in bottom-sediment samples collected from 10 sites on the Barron River Canal and from one site on the Turner River in October 1998 had patterns of distribution that indicated different sources. At some sites on the Barron River Canal, lead, copper, and zinc, normalized to aluminum, exceeded limits normally considered as background and may be enriched by human activities. Polynuclear aromatic hydrocarbons and p -cresol, normalized against organic carbon, had patterns of distribution that indicated local sources of input from a road or vehicular traffic or from an old creosote wood treatment facility. Phthalate esters and the traces elements arsenic, cadmium, and zinc were more widely distributed with the highest normalized concentrations occurring at the Turner River background site, probably due to the high percentage of fine sediment (74% less than 63 micrometers) and high organic carbon concentration (42%) at that site and the binding effect of organic carbon on trace elements and trace organic compounds. Low concentrations of pesticides or pesticide degradation products were detected in bottom sediment (DDD and DDE, each less than 3.5 µg/kg) and water (9 pesticides, each less than 0.06 µ/L), primarily in the northern reach of the Barron River Canal where agriculture is a likely source. Although a few contaminants approached criteria that would indicate adverse effects on aquatic life, none exceeded the criteria, but the potential synergistic effects of mixtures of contaminants found at most sites are not included in the criteria.

Florida

Water quality in southern Florida: Florida, 1996-98

Major influences and findings for water quality and biology in southern Florida, including the Everglades, are described and illustrated. Samples were collected to determine total phosphorus, dissolved organic carbon, pesticides, mercury, nitrate, volatile organic carbon compounds, and radon-222. Water-management, agricultural, and land-use practices are discussed. Sixty-three species of fish in 26 families were collected; 43 native species, 10 exotic or nonnative species, and 10 species of marine fish that periodically inhabit canals and rivers were identified.

Florida

USGS Science for Restoration of South Florida: The South Florida Ecosystem Program

As land and resource managers see the value of their resources diminish, and the public watches the environments they knew as children become degraded, there are increasing calls to restore what has been lost, or to build productive ecosystems that will be healthy and sustainable under the conditions of human use. The U.S. Geological Survey's (USGS) Placed-Based Studies Program was established to provide sound science for resource managers in critical ecosystems such as South Florida (fig. 1). The program, which began in south Florida in 1995, provides relevant information, high-quality data, and models to support decisions for ecosystem restoration and management. The program applies multi- and interdisciplinary science to address regional and subregional environmental resources issues.

Florida

Water quality in the southern Everglades and Big Cypress Swamp in the vicinity of the Tamiami Trail, 1996-97

The quality of water flowing southward in the Everglades and Big Cypress Swamp was characterized by three synoptic surveys along an 80-mile section of the Tamiami Trail and along a 24-mile transect down the Shark River Slough, by monthly sampling of a background reference site in the central Big Cypress Swamp, and by sampling of fish tissue for contaminants at several sites near the Trail. The quality of water along the Trail is spatially variable due to natural and human influences. Concentrations of dissolved solids and common ions such as chloride and sulfate were lowest in the central and eastern Big Cypress Swamp and were higher to the west due to the effects of seawater, especially during the dry season, and to the east due to canal drainage from the northern Everglades. Concentrations of total phosphorus tended to decrease from west to east along the 80-mile section of the Trail, and were usually about 0.01 milligram per liter or less in the Everglades. Short-term loads (based on average discharge for 4 days) of total phosphorus and total Kjeldahl nitrogen (ammonia plus organic nitrogen) across four gaged sections of the Tamiami Trail were highest in the Everglades near the S-12 structures primarily due to the relatively greater discharges in that section. Concentrations of dissolved solids and total phosphorus at the central Big Cypress Swamp site increased significantly during the dry season as waters ponded. Effects of nearby, upstream agricultural activities were evident at a site in the western Big Cypress Swamp where relatively high concentrations of total phosphorus, total mercury, and dissolved organic carbon and high periphyton biomass accumulation rates were measured and where several pesticides were detected. The most frequently detected pesticides along the Trail were atrazine (14 detections), tebuthiuron (11 detections), and metolachlor (5 detections), and most concentrations were less than 0.1 microgram per liter. DDT compounds were the only pesticides detected in fish from five sites. Total DDT ranged from 5 to 6 micrograms per kilogram in largemouth bass and from 11 to 17 micrograms per kilogram in Florida gar.

Florida

The south Florida environment: A region under stress

This report provides an overview of the environmental setting in South Florida and serves as review and framework for developing U.S. Geological Survey programs in the region. The report describes the predevelopment and the current (present-day) environmental conditions in South Florida with emphasis on the quantity and quality of water. The geographical area covered is the southern one-half of the State and includes the South Florida National Water-Quality Assessment study area and adjacent coastal waters. This study area covers about 19,500 square miles and is the watershed of the larger regional ecosystem. The regional ecosystem includes the coastal waters between Charlotte Harbor on the Gulf of Mexico and the St. Lucie River on the Atlantic Ocean and the lands that drain into these waters.

Florida

Physical, chemical, and biological characteristics of the Charlotte Harbor basin and estuarine system in southwestern Florida: A summary of the 1982-89 U.S. Geological Survey Charlotte Harbor assessment and other studies

The Charlotte Harbor estuarine system, having a surface area of about 270 square miles, averages about 7 feet in depth and is connected to deep water of the Gulf of Mexico through several passes and inlets between barrier islands. Three major rivers flow into the estuary--the Peace, the Myakka, and the Caloosahatchee. Freshwater and tidal flushing transport nutrients and other constituents from the basin through the estuary into the gulf. Flushing characteristics were evaluated using a two-dimensional hydrodynamic model. The model indicated that the time required to flush injected dye (simulated) from some subareas of the harbor was longer for reduced freshwater inflow than for typical freshwater inflow. After 30 days of simulation of reduced freshwater inflow, 42 percent of the dye injected into the upper harbor remained in the upper harbor, compared to 28 percent for typical freshwater inflow. The Charlotte Harbor estuary is usually well mixed or partially mixed in the vertical, but vertical salinity stratification does occur, primarily during late summer when freshwater inflows are greatest. A box model was developed that incorporated vertically averaged salinities to account indirectly for three-dimensional transport processes associated with vertical stratification. The box model predicts that under high (7,592 cubic feet per second) and average (2,470 cubic feet per second) freshwater inflows from the Peace and Myakka Rivers, 50 percent of the original water (present at the start of the model run) would be flushed from the northern part of the estuarine system into the Gulf of Mexico in 10 days and 20 days, respectively. The distribution of plant nutrients in the Charlotte Harbor Estuary is affected by nutrient inputs, freshwater and tidal flushing, mixing, and recycling processes in the estuary. The distributions of total phosphorus and orthophosphate are affected mainly by river input and physical mixing. The distribution of ammonia nitrogen is variable and is related more to recycling within the estuary than to input from the rivers. Ammonia concentrations increase in deeper water, probably in response to vertical salinity stratification and low concentrations of dissolved oxygen that foster regeneration of ammonia from bottom sediments. The distribution of nitrite plus nitrate nitrogen is nonconservative--concentrations are high in the rivers and decrease more rapidly in the estuary than expected due to dilution with sea water, probably because of phytoplankton uptake. Phytoplankton productivity and biomass are usually greatest during late summer near the mouths of the tidal rivers when freshwater inflow and nutrient loading are greatest. The highly colored freshwater runoff reduces light penetration and phytoplankton productivity in regions of the estuary where salinity is less than about 10 parts per thousand, but the nutrient-rich, colored water is diluted by seawater at midsalinities (10-20 parts per thousand) so that availability of light increases and inorganic nitrogen concentrations are still high enough to stimulate productivity and growth of phytoplankton. In much of the estuary, salinity is greater than 20 parts per thousand, and availability of inorganic nitrogen, not light, limits productivity and growth. Although the Charlotte Harbor estuarine system is relatively undisturbed, much of its basin has been altered by human activities. Streamflow decreased substantially during 1931-84 in parts of the Peace River, probably because of ground-water withdrawals in the basin. Nutrient concentrations generally increased in the rivers during 1970-85, because of an increase in the flow of wastewater and agricultural runoff. The concentrations of phosphorus are naturally high in the Peace River because of extensive phosphate deposits in the basin. The phosphate deposits also are relatively rich in radionuclides of the uranium-238 series, including radium-226. In the upper basin, these deposits are exposed in the riverbed. Extensive phosphate mining and processing have exposed additional deposits to surface runoff. Periodic spills of phosphate sediments (slimes) have contributed additional phosphorus and radium-226 to the river and estuary. A single spill can contribute a phosphorus load equal to the annual loading in the Peace River at Arcadia. The projected increase in population in the basin by the year 2020 would generate an additional 60 million gallons per day of domestic wastewater over that generated during 1980, which would increase nitrogen loading in the basin by more than 3 tons per day. Intensified agricultural and industrial developments, particularly expanding citrus production and phosphate mining, could generate additional loads of nutrients and a variety of inorganic and organic contaminants. Increased inputs of nutrients, particularly nitrogen, could encourage growth and increase abundance of phytoplankton and benthic and epiphytic algae. If water were less colored as a result of reduced freshwater inflow, undesirable algal growth could be exacerbated because of increased availability of light. Increased abundance of phytoplankton and other algae could likely change dissolved-oxygen concentrations in the estuary, resulting in greater day-to-night fluctuations and the possible depletion of dissolved oxygen in deep water. At the present time, near-anaerobic conditions occur for days or weeks in the deep water (more than 9 feet) of the northern harbor during late summer. These conditions could become more persistent with time and over wider areas, if phytoplankton and other algae increase in abundance and in their contribution to benthic oxygen demand. An increased abundance of phytoplankton and other algae also would reduce light penetration and adversely affect seagrasses.

Florida

Sediment concentrations and loads in the Loxahatchee River estuary, Florida, 1980-82

This study was conducted to estimate the magnitude of sediment loads and the general spatial and temporal patterns of sediment transport in the Loxahatchee River estuary, Florida. Mean concentrations of suspended sediment generally were higher in the Jupiter Inlet area than in the remainder of the embayment area. Concentrations of suspended sediment varied with season and weather conditions. Concentrations in selected tributaries following Tropical Storm Dennis in August 1981 immediately increased as much as 16 times over concentrations before the storm. Suspended-sediment loads from the tributaries were also highly seasonal and storm related. During a 61-day period of above-average rainfall that included Tropical Storm Dennis, 5 major tributaries discharged 926 tons (short) of suspended sediment to the estuary, accounting for 74 percent of the input for the 1981 water year and 49 percent of the input for the 20-month study period. Suspended-sediment loads at Jupiter Inlet and at the mouth of the estuary embayment on both incoming and outgoing tides far exceeded tributary loads, but the direction of long-term, net tidal transport was not determined. (USGS)

Water-Resources Investigations Report

Algal conditions in the Caloosahatchee River (1975-79), Lake Okeechobee to Franklin Lock, Florida

Maximum numbers of suspended algae occurred in late spring and early summer, in each of the years 1975-79, in the Caloosahatchee River. Numbers exceeded 100,000 cells per milliliter at all stations sometime during the study. Concentrations decreased during late summer and autumn and were low during winter, except in January 1979 when numbers at most sites exceeded 100,000 cells per milliliter. The January 1979 bloom coincided with large discharges from Lake Okeechobee. During previous winters, discharges and algal numbers were lower. During other seasons, algal blooms occurred most frequently under low-flow or stagnant conditions. The upstream site at Moore Haven, which had the least discharge and was most stagnant, had consistently higher algal concentrations than downstream sites. Blue-green algae were dominant in the river during the summer at the upstream site throughout the year. The percentage of blue-green algae decreased downstream. Concentrations of nitrite plus nitrate nitrogen were inversely correlated with concentrations of algae and decreased to near zero during algal blooms. The low concentrations of these forms of inorganic nitrogen relative to other major nutrients probably favor blue-green algae and limit growth of other algae. Contributions by the basin tributaries to the nutritive condition of the river were small because concentrations of nutrients, algal growth potential, and algae in the tributaries were generally less than those in the river. (USGS)

Florida

Physical, Hydrological, and Biological Characteristics of the Loxahatchee River Estuary, Florida

The Loxahatchee River estuary empties into the Atlantic Ocean at Jupiter Inlet in southeastern Florida. Although relatively small, the estuary is important for its esthetic value and for its sport fishing, boating, recreation, tourism, and prime residential development. In recent years, the condition of the estuary has become of concern to many citizens and agencies of the State. In response to this concern, the U.S. Geological Survey planned and carried out an in-depth environmental investigation. The events that led to the investigation and the objectives of the investigation are outlined in a recent U.S. Geological Survey report by McPherson and Sabanskas (WRI 80-1109).

Water-Resources Investigations Report

Hydrologic and land-cover features of the Loxahatchee River Basin, Florida

This map report represents the first published product of the Loxahatchee River estuary assessment, and primarily fulfills the first objective as outlined in the report. It presents an overview of the major physical features of the basin and presents selected information on the U.S. Geological Survey assessment. The report includes a photomosaic map with the names of major tributaries, the location of selected U.S. Geological Survey stations, basin and subbasin boundaries, and direction of surface-water flow. The scale of the map (1 inch = 1 mile) allows a synoptic view with adequate detail of physical features. The report also includes information on the types of soil and land use in the basinand on characteristics of the estuary. The map report provides a work base for future interpretive reports.

Water-Resources Investigations Report