Interim report on the ground-water resources of Seminole County, Florida

Salt-water encroachment is undoubtedly the problem of most concern to users of ground water in Florida. This is a problem in many coastal areas where water levels are lowered excessively by heavy pumping. It is a problem also in some inland areas where the water-bearing formations contain salty water at relatively shallow depths. Among the coastal areas where wells have become contaminated with salt water are Pinellas County and the Miami area of Dade County. Inland areas where wells are likely to become contaminated with salt water include Seminole County and the southwestern part of Volusia County. The purpose of the investigation is to make a detailed study of the geology and ground-water resources of the county with special emphasis on the problems associated with declining water levels and salt-water contamination. This report reviews briefly the progress of the investigation through February 1954. (PDF contains 43 pages.)

Interim report on the ground-water resources of Manatee County, Florida

A large part of western Manatee County is devoted to the growing of winter vegetables and citrus fruits. As in most of peninsular Florida, rainfall in the county during the growing season is not sufficient for crop production and large quantites of artesian water are used for irrigation. The large withdrawals of artesian water for irrigation result in a considerable decline of the artesian head in the western part of the county. This seasonal decline of the artesian head has become larger as the withdrawal of artesian water has increased. The lowering of the fresh-water head in some coastal areas in the State has resulted in an infiltration of sea water into the water-bearing formations. The presence of salty water in the artesian aquifer in parts of the coastal area of Manatee County indicates that sea water may also have entered the waterbearing formations in this area as a result of the decline of artesian pressure during the growing season. The purpose of the investigation is to make a detailed study of the geology and ground-water resources of the county, primarily to determine whether salt-water encroachment has occurred or is likely to occur in the coastal area. (PDF contains 38 pages.)

Interim report on surface water resources and quality of waters in Lee County, Florida

Report seeks to address following questions: 1. Where within Lee County are surface supplies of water located? 2. What are the variations in this supply? 3. What can be done to provide better answers to questions 1 and 2 than are available at the present time? (PDF contains 76 pages.)

Interim report on salt-water encroachment in Dade County, Florida

Recently there has been much activity in reclaiming the low-lying coastal areas of Dade County for residential use, by the addition of fill. The fill is obtained by digging canals both normal to and parallel to Biscayne Bay. The canals serve the additional purpose of providing an access to the Bay for boats. A problem needing to be considered is the effect that these canals will have on the ground-water resources. It is expected that the canals will have little effect on ground water in parts of the county distant from the coast, but their effect in coastal areas is a matter of concern. In order to predict what, may happen in the vicinity of these new canals if they are not equipped with adequate control structures, it is instructive to review what has happened in the vicinity of similar canals in the past. The U. S. Geological Survey, in cooperation with Dade County, the cities of Miami and Miami Beach, the Central and Southern Florida Flood Control District, and the Florida Geological Survey has collected water-level and salinity data on wells and canals in Dade County since 1939. Some of the agencies named, and others, collected similar data before 1939. Analysis of all the data shows that sea water in the Atlantic Ocean and Biscayne Bayis the sole source of salt-water contamination in the Biscayne aquifer of the Dade County area. (PDF has 19 pages.)

Ground-water resources of the Stuart area, Martin County, Florida

Because the Stuart area is, at times, surrounded on three sides by saline water, the underlying fresh-water aquifer is vulnerable to salt-water encroachment. With progressively larger withdrawals of ground water for public and private supplies, the possibility of salt-water contamination of freshwater supplies is increased. (PDF contains 51 pages.)

Changes in the chloride content of ground water in Pinellas County, Florida between 1947 and 1956

In December 1956 the U. S. Geological Survey, in cooperation with the Florida Geological Survey and the Board of County Commissioners of Pinellas County, collected waterlevel and chloride content of water in 94 wells in Pinellas County. First sampled in 1947, resampling and reanalyzing the water from these wells was used to determine the change in the chloride content of the ground water from 1947 to 1956. The chloride content of ground water is generally a reliable indication of the contamination of ground water by sea water, as 90 percent of the dissolved solids of sea water are chloride salts. (PDF contains 15 pages.)

Interim report on geology and ground-water resources of Indian River County, Florida

In the area of this investigation a partial inventory was made of the estimated 2,000 existing wells to obtain information on location, depth, and yield of representative wells. Also, data were obtained on the quality of water from the various aquifers, and on the fluctuation of water levels in certain wells in the Floridan aquifer. The hydraulic characteristics of the Floridan aquifer at several sites were determined by means of pumping tests. (PDF has 80 pages.)

Record of wells in Manatee County, Florida

A detailed study of the geology and ground-water resources of Manatee County (fig. 1) was made during the period from 1950 to 1955. This report contains a table of well records that was compiled from data collected during that investigation. The well-numbering system used in the table is based on latitude and longitude. (PDF contains 204 pages.)

Interim report on surface water resources of Baker County, Florida

The principal sources of surface-water supplies inBaker County are the St. Marys River and its tributaries. However, the flow of many of the small tributaries is intermittent, and without storage they are not dependable sources of supply during sustained periods of deficient rainfall. Of the six stream-gaging stations in Baker County for which complete records are available, one has been in operation for 31 years and provides a long-term record upon which to base correlative estimates for extending the short-term records at the other stations. All available streamflow data to 1957 have been summarized in graphic or tabular form. The hydrologic balance between minimum streamflows and increased evaporation losses afforded by potential shallow reservoirs provides design criteria for determining the maximum surface area of effective reservoir that can be created at a selected site within Baker County. This information has been presented in graphic and tabular form in the report. (PDF has 37 pages.)

Record of wells in the Ruskin area of Hillsborough County, FLorida

A detailed study of the geology and ground-water resources of the Ruskin area (fig. 1) was made during the period from 1950 to 1955, by the U. S. Geological Survey in cooperation with the Florida Geological Survey and the Board of County Commissioners of Hillsborough County. The results of this study are given in a report by Harry M. Peek entitled "The artesian water of the Ruskin area of Hillsborough County, Florida" and published by the Florida Geological Survey as Report of Investigations No. 21. This report contains tables of well records that were compiled from data collected during that investigation. The well-numbering system used in the tables is based on latitude and longitude. (PDF contains 88 pages.)

Record of wells in Volusia County, Florida

A detailed study of the geology and ground-water resources of Volusia County, on the eastern coast of Florida (fig. 1), was made during the period 1953-57 by the U. S. Geological Survey in cooperation with the Florida Geological Survey and the cities of Daytona Beach, New Smyrna Beach, and Port Orange. The results of this study have been published by the Florida Geological Survey in the following reports: Information Circular No. 8, entitled "Interim Report on Ground-Water Resources of Northeastern Part of Volusia County, Florida, " by Granville G. Wyrickand Willard P. Leutze;, and Report of Investigations No. 22, entitled "Ground-Water Resources of Volusia County, Florida, " by Granville G. Wyrick. This report contains a table of well records that was compiled from data collected during that investigation. longitude. (PDF contains 100 pages.)

Surface water resources of Polk County, Florida

The rapid increase in population in Polk County during the last decade has been accompanied by a several-fold increase in the number and complexity of problems pertaining tothe use andcontrolof the streams andlakes of the county. The increase in problems has increased the need for more information about the occurrence and movement of surface water. The primary purpose of this report is to give that information. Its secondary purpose is to give information that will promote an understanding of the nature and causes of the problems or that will aid in arriving at practical solutions. (PDF contains 133 pages.)

Reconnaissance of the ground-water resources of the Fernandina area, Nassau County, Florida

Practically all water for municipal and industrial use in the Fernandina area is supplied by artesian wells. In recent years, the use of artesian water in the area has increased to meet the needs of expanding industry and increasing population. The total industrial and municipal pumpage has increased from approximately 35 million gallons per day in 1941 to approximately 50 million gallons per day in 1959. Correlated with the increase in water use is the constant decline in the artesian pressure in the area. In many other areas in Florida, such a decline in artesian pressure has resulted in salt-water intrusion into the fresh-water supply.An intrusion of salt water in the Fernandina area would contaminate the existing fresh-water supply and would result in a hardship for the population and seriously injure the economy. Recognizing the threat to the fresh-water supplies of this area, the U. S. Geological Survey in cooperation with the Florida Geological Surveymade a reconnaissance to determineif there has been any intrusion of salt water into the fresh-water supply or if there is any danger of future intrusion. (PDF contains 28 pages.)

Eurasian watermilfoil biomass associated with insect herbivores in New York

A study of aquatic plant biomass within Cayuga Lake, New York spans twelve years from 1987-1998. The exotic Eurasian watermilfoil ( Myriophyllum spicatum L.) decreased in the northwest end of the lake from 55% of the total biomass in 1987 to 0.4% in 1998 and within the southwest end from 50% in 1987 to 11% in 1998. Concurrent with the watermilfoil decline was the resurgence of native species of submersed macrophytes. During this time we recorded for the first time in Cayuga Lake two herbivorous insect species: the aquatic moth Acentria ephemerella , first observed in 1991, and the aquatic weevil Euhrychiopsis lecontei , first found in 1996 . Densities of Acentria in southwest Cayuga Lake averaged 1.04 individuals per apical meristem of Eurasian watermilfoil for the three-year period 1996-1998. These same meristems had Euhrychiopsis densities on average of only 0.02 individuals per apical meristem over the same three-year period. A comparison of herbivore densities and lake sizes from five lakes in 1997 shows that Acentria densities correlate positively with lake surface area and mean depth, while Euhrychiopsis densities correlate negatively with lake surface area and mean depth. In these five lakes, Acentria densities correlate negatively with percent composition and dry mass of watermilfoil. However, Euhrychiopsis densities correlate positively with percent composition and dry mass of watermilfoil. Finally, Acentria densities correlate negatively with Euhrychiopsis densities suggesting interspecific competition.

Evaluation of the quantity and quality of the water resources of Volusia County, Florida

This report amplifies and refines some of the data already issued covering the water resources of Volusia County, which were published as Report of Investigations No. 21. The work in the report was accomplished as a cooperative program between the Department of Natural Resources, the U. S. Geological Survey and the Board of County Commissioners of Volusia County. Volusia County is almost totally dependent upon the water which falls upon the county and has a recharge area contained along the western portion and the central portions of the county. Excellent water is produced in the areal recharge and it is anticipated that this data will expand the existing knowledge of the water resources to permit the development of a great capacity for existing utilities and to offset and solve some of the problems now in the area. (PDF has 71 pages.)