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J. D. Fretwell

Publications and source records attributed to J. D. Fretwell.

6 recordsLinked to original sources
USGS1985

Water resources and effects of development in Hernando County, Florida

In spite of the hill and valley terrain in the Brooksville Ridge area of Hernando County, Florida, little surface drainage occurs within the county. Recharge to the Floridan aquifer system occurs as infiltration of precipitation within the county or as ground-water flow from Sumter County to the east and Pasco County to the south. Discharge is principally to the Gulf of Mexico, but some ground water flows north into Citrus County before it reaches the Gulf. The Floridan aquifer system is generally unconfined. Water quality is generally good except near the coast where high chloride occurs. Water from the Floridan aquifer system accounted for 87 percent of the water used for irrigation, industry, and rural and public supply in 1982. Sixty-seven percent of this water was used by industry. Rock mining, the major industry, used 99 percent of the industrial water. The anticipated increase in population in the county between 1982 and 2000 will increase demand for water primarily from public water-supply systems. This higher demand will cause about a 1 percent reduction in flow from Weeki Wachee Springs, but little change in lake levels or saltwater intrusion will occur if the projected additional supplies are developed far enough inland from the coast. (USGS)

Water-Resources Investigations Report↗
USGS1983

Ground-water resources of coastal Citrus, Hernando, and southwestern Levy counties, Florida

Ground water in the coastal parts of Citrus, Hernando, and Levy Counties is obtained almost entirely from the Floridan aquifer. The aquifer is unconfined near the coast and semiconfined in the ridge area. Transmissivity ranges from 20,000 feet squared per day in the ridge area to greater than 2,000,000 feet squared per day near major springs. Changes in the potentiometric surface of the aquifer are small between the wet and dry seasons. Water quality within the study area is generally very good except immediately adjacent to the coast where saltwater from the Gulf of Mexico poses a threat to freshwater supply. This threat can be compensated for by placing well fields a sufficient distance away from the zone of transition from saltwater to freshwater so as not to reduce or reverse the hydraulic gradient in that zone. Computer models are presently available to help predict the extent of influence of ground-water withdrawals in an area. These may be used as management tools in planning ground-water development of the area. (USGS)

Water-Resources Investigations Report↗
USGS1982

Position of the saltwater-freshwater interface in the upper part of the Floridan Aquifer, southwest Florida, 1979

Ground-water withdrawals in southwest Florida are increasing because of urban growth, industrial expansion and increased agricultural irrigation. As a result, the potentiometric surface of the Floridian aquifer has been lowered in some areas, allowing seawater to encroach into the aquifer and threaten the freshwater resources of the area. Effective management of groundwater is needed to control the encroachment and protect the freshwater aquifer.

Florida↗