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L. A. Bradner

Publications and source records attributed to L. A. Bradner.

At least 37 records · Page 2Linked to original sources
USGS1989

Artificial recharge to the Floridan aquifer system, Orlando Area, Central Florida

Approximately 400 drainage wells exist in Orange County, central Florida. The rate of recharge through drainage wells is limited by the rate of surface flow to the wells; the hydraulic properties of weirs, overflow pipes, and well casings; or the water level above the top of the casing. The rate commonly is not limited by the hydraulic properties of the very transmissive aquifer system.

Conference Paper↗
USGS1988

Hydrology of the Floral City Pool of Tsala Apopka Lake, west-central Florida

Tsala Apopka Lake, in west-central Florida, has an area of about 19,000 acres and is divided into three water-management pools, with the Floral City Pool, the most upgradient. The Floral City Pool, which has a surface area of approximately 4,750 acres, contains an extensive combination of lakes, wetlands, and connecting canals. The Pool receives inflow from the Withlacoochee River through two canals. Outflow is through one manmade canal and one natural slough. Canal flow is partially controlled by manmade structures. A cumulative deficit of 19.4 inches of rainfall from August 1984 through May 1985 reduced surface-water inflow to the Floral City Pool to about 0.5 cu ft/sec by May 1985. During May 1985, pool levels declined approximately 0.04 ft/day. By the end of May, there was no observable outflow. From June 1985 through September 1985, 39.8 inches of rainfall caused above-average inflow to the Floral City Pool and a pool-level increase of 6.2 ft. The inflow of 340 CFS nearly equaled the outflow of 338 CFS by the end of September. (USGS)

Water-Resources Investigations Report↗
USGS1987

Potentiometric surface of the upper Floridan aquifer in central Sumter County, Florida, September 1986

This map shows the potentiometric surface of the Upper Floridan aquifer in central Sumter County, Florida, for September 1986. The Upper Floridan aquifer is the principal source of potable water in the area. The focus of the map is in the Jumper Creek Canal area where mine pumpage affects water levels. Water levels rose approximately 2 to 3 feet in the southern part of the study area between May and September but remained stable in the northern part. The potentiometric surface ranged in altitude from more than 90 ft in the southeastern part of the county to less than 40 feet northwest of Lake Panasoffkee in the west-central area.

Florida↗
USGS1987

Potentiometric surface of the upper Floridan aquifer in the St. Johns River Water Management District and vicinity, Florida, September 1987

This map shows the potentiometric surface of the Upper Floridan aquifer in the St. Johns River Water Management District and vicinity for September 1987. The Upper Floridan aquifer is the principal source of potable water in the area. Water level measurements were made on approximately 1,000 wells and on several springs. The potentiometric surface is shown mostly by 5-foot contour intervals. The potentiometric surface ranged from 129 feet above sea level in Polk County to 77 feet below sea level in Nassau County. Water levels in most key wells ranged from 0 to 10 feet below in May 1987 levels in response to the lack of recharge from rainfall and an attendant increase in pumpage. Declines of about 0 to 3 feet from May 1987 levels were common in most areas of the district. However, the largest declines from May 1987 levels, as much as 7 to 10 feet, were mostly in well fields along the coastline. Many levels in the district were equal to or lower than the average levels of September 1986.

Florida↗
USGS1987

Ground-water resources of Flagler County, Florida

Groundwater is the only significant source of potable water in Flagler County. Usable water occurs in the Upper Floridan aquifer, the intermediate population is expected to place stresses on the water resources of the county. Although rainfall averages almost 50 in/yr, most of the water leaves as evapotranspiration and streamflow. Less than 1 in/yr recharge may be occurring to the Upper Floridan aquifer, the highest yielding aquifer. The Upper Floridan aquifer consists of the Avon Park Formation, the Ocala Limestone, and the basal dolomitic limestone of the Hawthorne. Use of the Upper Floridan aquifer for public water supply is limited in most of the county because it contains marginally potable or brackish water. It is used extensively for agricultural irrigation. The intermediate aquifer system consists of thin, discontinues lenses of sand, shell, and limestone between clays overlying the Floridan aquifer system. The intermediate aquifer system is an important part of the public water supply of the county because of the good quality of the water. The intermediate aquifer system has variable yields because of the discontinuous lenses. The surficial aquifer system is composed of sand and shell with varying fractions of finer materials. Well yields are small in the west and central parts of Flagler County, but the surficial aquifer system is an adequate source of domestic supply on the barrier island. A zone of freshwater in the surficial aquifer system is very important in the Hammock area, being the local source of most domestic supply in the area. Changes in hydrologic conditions from the 1950 's include a long-term decline in water levels in the Upper Floridan aquifer coincident with lower-than-average rainfall and a greater seasonal fluctuation of water levels. Chloride concentrations of water in the Upper Floridan aquifer do not appear to have changed significantly, presently ranging from 7 to 3,700 mg/L. Development will place stress on the aquifers and may result in upconing of brackish water in pumping centers and in lateral saltwater intrusion in coastal areas. (Author 's abstract)

Water-Resources Investigations Report↗
USGS1986

Hydrogeology of the Lake Miona area, northeast Sumter County, Florida

The Lake Miona area, in northeast Sumter County, is characterized by karstic depressions that contain lakes, ponds, and marshes that drain vertically to the upper Floridan aquifer. Lake Miona, Black Lake, and Cherry Lake are the prominent water features of the area. When the lake levels are lowest, the lakes are not connected, but at higher levels, they become connected and water flows eastward from Lake Miona through Black Lake to Cherry Lake. The chemical and biological conditions in the lakes are such that, although they support a large population of submerged aquatic plants, no problem with algae blooms was observed. (USGS)

Water-Resources Investigations Report↗
USGS1985

Potentiometric surface of the upper Floridan Aquifer in central Sumter County, Florida, May 1985

This map presents the potentiometric surface of the Floridan aquifer system in central Sumter County, Florida, for May 1985. The Floridan aquifer system is the principal source of portable water in the area. The focus of the map is the potentiometric surface in the Jumper Creek Canal area. Water-level measurements were made on approximately 60 wells. The potentiometric surface ranged in altitude from more than 90 feet in the southeastern part of the county to less than 35 feet northwest of Lake Panasoffkee in the west-central area. (USGS)

Open-File Report↗
USGS1985

Potentiometric surface of the upper Floridan Aquifer in central Sumter County, Florida, September 1985

The map presents the potentiometric surface of the Upper Floridan aquifer in central Sumter County, Florida, for September 1985. The Upper Floridan aquifer is the principal source of potable water in the area. The focus of the map is the potentiometric surface in the Jumper Creek Canal area. Water level measurements were made on approximately 60 wells. The potentiometric surface ranged in altitude from more than 90 feet in the southeastern part of the county to less than 40 feet northwest of Lake Panasoffkee in the west-central area. (USGS)

Open-File Report↗
USGS1984

Potentiometric surface of the upper Floridan aquifer in central Sumter County, Florida, September 1984

This map presents the potentiometric surface of the Upper Floridan aquifer in central Sumter County, Florida, for September 1984. The Floridan aquifer system is the principal source of potable water in the area. The focus of the map is the potentiometric surface in the Jumper Creek Canal area. Water-level measurements were made on approximately 60 wells. The potentiometric surface ranged in altitude from more than 90 feet in the southeastern part of the county to less than 40 feet northwest of Lake Panasoffkee in the west-central area. (USGS)

Open-File Report↗
USGS1984

Potentiometric surface of the upper Floridan Aquifer in central Sumter County, Florida, May 1984

This map presents the potentiometric surface of the upper Floridan aquifer in central Sumter County, Florida, for May 1984. The Floridan aquifer system is the principal source of potable water in the area. The focus of the map is the potentiometric surface in the Jumper Creek Canal area. Water level measurements were made on approximately 60 wells. The potentiometric surface ranged in altitude from more than 90 feet in the southeastern part of the county to less than 40 feet northwest of lake Panasoffkee in the west-central area. (USGS)

Open-File Report↗
USGS1983

Potentiometric surface of the Floridan Aquifer in central Sumter County, Florida, May 1982

This map presents the potentiometric surface of the Floridan aquifer in central Sumter County, Florida, for May 1982. The Floridan aquifer is the principal source of potable water in the area. The focus of the map is the potentiometric surface in the Jumper Creek Canal area for the low water-level period. Water-level measurements were made at approximately 60 wells. The potentiometric surface ranged in altitude from more than 95 feet in the southeast part of the county to less than 35 feet northwest of Lake Panasoffkee in the west-central area. (USGS)

Open-File Report↗
USGS1983

Potentiometric surface of the Floridan Aquifer in central Sumter County, Florida, September 1982

This map presents the potentiometric surface of the Floridan aquifer in central Sumter County, Florida, for September 1982. The Floridan aquifer is principal source of potable water in the area. The focus of the map is the potentiometric surface in the Jumper Creek Canal area for the high water-level period. Water-level measurements were made on approximately 60 wells. The potentiometric surface ranged in altitude from more than 90 feet in the southeast part of the county to less than 40 feet northwest of Lake Panasoffkee in the west-central area.

Open-File Report↗
USGS1983

Potentiometric surface of the Floridan Aquifer in central Sumter County, Florida, May 1983

This map presents the potentiometric surface of the Floridan aquifer in central Sumter County, Florida, for September 1983. The Floridan aquifer is the principal source of potable water in the area. The focus of the map is the potentiometric surface in the Jumper Creek Canal area for the high water-level period. Water level measurements were made on approximately 60 wells. The potentiometric surface ranged in altitude from more than 90 ft in the southeast part of the county to less than 40 ft northwest of Lake Panasoffkee in the west-central area. (USGS)

Open-File Report↗
USGS1982

Potentiometric surface of the Floridan Aquifer in central Sumter County, Florida, September 1981

This map presents the potentiometric surface of the Floridan aquifer in central Sumter County, Florida, for September 1981. The Floridan aquifer is the principal source of potable water in the area. The focus of the map is the potentiometric surface in the Jumper Creek Canal area for the high water-level period. Water-level measurements were made on approximately 60 wells. The potentiometric surface ranged in altitude from more than 85 feet in the southeast part of the county to less than 35 feet northwest of Lake Panasoffkee in the west-central area. (USGS)

Open-File Report↗