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L. R. Mills

Publications and source records attributed to L. R. Mills.

At least 19 recordsLinked to original sources
USGS1984

Hydrogeology of the Sulphur Springs area, Tampa, Florida

The Sulfur Springs area includes about 56 square miles in west-central Hillsborough County, Florida. The north-central part of the city of Tampa is highly urbanized; the north-west part of the area is rural or undeveloped. The area has numerous sinkholes, two of which are used as retention basins for urban storm runoff. An intermittent stream discharges into a sinkhole that is hydraulically connected with the Floridian aquifer. A well-developed cavity system occurs in the upper part of the aquifer in the southwestern and southeastern parts of the area. Groundwater velocities of 4,200 to 9,200 feet per day were determined from dye tests conducted in a sinkhole area north of Sulfur Springs. Sulfur Springs provides the city of Tampa a supplemental water supply of 20 million gallons per day. Periodically, the spring pool is closed to swimming because of the high bacteria counts in the water. The source of bacteria appears to be an internally drained sinkhole area north of the spring. In 1980, groundwater use in the study area, excluding withdrawals from Sulphur Springs, was 7.2 million gallons per day, largely for public water supplies. The city of Tampa pumped an average of 48.5 million gallons per day from the Tampa Dam Reservoir on the Hillsborough River. (USGS)

Water-Resources Investigations Report↗
USGS1980

Ground-water levels in selected well fields and in west-central Florida, May 1980

The water table in the surficial aquifer and the potentiometric surface of the Floridan aquifer in a 1,200-square-mile area in west-central Florida are mapped semiannually by the U.S. Geological Survey. Maps are prepared showing water levels measured in wells each May to coincide with seasonal low levels and each September to coincide with seasonal high levels. The mapped area shows 14 well-field areas that supplied 155 million gallons to municipalities on May 12, 1980. The water is withdrawn from the Floridan aquifer, the major aquifer in Florida. The effect of localized withdrawal of ground water is shown on the maps as depressions in both the potentiometric and water-table surfaces. Water levels were lower in May 1980 than in September 1979 and a little higher than the average May levels. Change of water levels ranged from a decrease of 12 feet at Verna well field to an increase of 7 feet at Eldridge-Wilde well field. (USGS)

Open-File Report↗
USGS1980

Hydrologic monitoring program in Eldridge-Wilde and East Lake Road well-field areas, Pinellas and Hillsborough counties, Florida, 1978

This report describes the observation-well network in Eldridge-Wilde and East Lake Road well-field areas, Pinellas and Hillsborough Counties, Florida. Data obtained in 1978 from the network in and adjacent to the two well fields, as well as rainfall and pumpage records, are presented. The Southwest Florida Water Management District has established regulatory water-level limits in four observation wells and water-quality limits in three observation wells. Water levels dropped below regulatory limits in the spring of 1978 in three wells. Chloride concentrations in 1978 remained above regulatory limits for the entire year in one well and exceeded the limit during the late spring in the other two deep wells, both west of Eldridge-Wilde well field. (USGS)

Open-File Report↗
USGS1980

Ground-water levels in selected well fields and in west-central Florida, September 1979

The water table in the surficial aquifer and the potentiometric surface of the Floridan aquifer in a 1,200-square-mile area in west-central Florida are mapped semiannually by the U.S. Geological Survey. Maps are based on water levels measured in wells each May to coincide with seasonal low levels, and each September to coincide with seasonal high levels. The mapped area shows 16 well fields which supplied 123.7 million gallons to municipalities on September 18, 1979. The water is withdrawn from the Floridan aquifer, the major aquifer in Florida. The effect of localized withdrawal of ground water is shown on the maps as depressions in both the potentiometric and water-table surfaces. Water levels were generally higher in September 1979 than in May 1979 and higher than the average September levels. Change of water levels ranged from an increase of 15 feet at Cosme well field to a decrease of 9 feet at Verna well field.

Florida↗
USGS1980

Ground-water levels in selected well fields and in west-central Florida, September 1980

The water table in the surficial aquifer and the potentiometric surface of the Floridan aquifer in a 1,200-square-mile area in west-central Florida are mapped semiannually by the U.S. Geological Survey. Maps are based on water levels measured in wells each May to coincide with seasonal low levels and each September to coincide with seasonal high levels. The mapped area shows 14 well fields that supplied 141.8 million gallons to municipalities on September 18, 1980. The water is withdrawn from the Floridan aquifer, the major aquifer in Florida. The effect of localized withdrawal of ground water is shown on the maps as depressions in both the potentiometric and water-table surfaces. Potentiometric levels in the Floridan aquifer were higher in September 1980 than in May 1980 and generally lower than in September 1979. Annual change of water levels ranged from a decrease of 6 feet at Morris Bridge well field to an increase of 2 feet at Eldridge-Wilde well field. (USGS)

Open-File Report↗
USGS1979

Potentiometric surface of Floridan Aquifer, southwest Florida Water Management District and adjacent areas, May 1979

A May 1979 potentiometric-surface map depicts the annual low water-level period. Potentiometric levels declined 4 to 21 feet between September 1978 and May 1979, in the citrus and farming sections of southern Hillsborough, northern Hardee, southwestern Polk, northwestern DeSoto, and Manatee Counties. Water levels in these areas are widely affected by pumping for irrigation and have the greatest range in fluctuations. Water-level declines ranged from 0 to 6 feet in coastal, northern, and southern areas of the Water Management District. Generally potentiometric levels were higher than previous May levels due to heavy rains in April and May. In parts of Hillsborough, Pasco, and Pinellas Counties, May 1979 potentiometric levels were 18 feet higher than those of September 1978.

Florida↗
USGS1979

Water table in the surficial aquifer and potentiometric surface of the Floridan Aquifer in selected well fields, west-central Florida, May 1979

The water table is the surficial aquifer and the potentiometric surface of the Floridan aquifer in a 1,200-square-mile area in west-central Florida are mapped semiannually by the U.S. Geological Survey. Maps are prepared showing water levels measured in wells each May to coincide with seasonal low levels, and each September to coincide with seasonal high levels. The mapped area shows 16 well fields which supplied 128 million gallons to municipalities on May 15, 1979. The water is withdrawn from the Floridan aquifer, the major aquifer in Florida. Water levels were significantly higher in May 1979 than in May 1978. Heavy rains on May 7 and 8th deluged the well-field areas with 2 to 18 inches of rain. The maximum increase in water levels from May 1978 to May 1979 was more than 8 feet at the Eldridge-Wilde well field. (USGS)

Open-File Report↗
USGS1978

Potentiometric surface of the Floridan Aquifer, Southwest Florida Water Management District and adjacent areas, September 1978

A September 1978 potentiometric-surface map depicts the annual high water-level period of the Floridan aquifer in the Southwest Florida Management District. Potentiometric levels increased 10 to 25 feet between May 1978 and September 1978, in the citrus and farming sections of southern Hillsborough, northern Hardee, southwestern Polk and Manatee Counties. These areas are widely affected by pumping for irrigation and have the greatest fluctuations in water-levels between the low and high water-level periods. Water-level rises in coastal, northern and southern areas of the Water Management District ranged from 0 to 10 feet. (Woodard-USGS)

Open-File Report↗
USGS1978

Ground water withdrawn for municipal, industrial, and irrigation use in the Upper Peace and Alafia River basins, west-central Florida, 1970-74

Data are presented for ground-water withdrawals for municipal, industrial and irrigation use in the upper Peace and Alafia River basins during 1970-71. Within the 1,160-square-mile study area, the principal source of ground water is the Floridan aquifer. Methods used to determine ground-water withdrawal include: metering water use; relating measured well discharge to power consumption of pumping time; and relating water use to phosphate production, citrus irrigation or processing. About 90 percent of municipal pumpage is metered, and annual pumpage increased from 11,165 million gallons in 1970 to 13,455 in 1974. Water use per ton of phosphate produced is estimated to be 3,320 gallons per ton prior to 1971 and 2,460 gallons per ton from 1971 through 1974. Estimated ground-eater use by the phosphate industry has declined from 93.3 billion gallons in 1970 to 78.7 in 1974. Citrus irrigation pumpage is obtained by extrapolating pumpage obtained from pilot areas of unmeasured areas and has declined from 33.4 billion gallons in 1970 to 31.3 in 1974. The citrus processing industry used about 4.9 billion gallons in 1970 and about 5.9 in 1974. (Woodard-USGS)

Open-File Report↗
USGS1978

Water table in the surficial aquifer and potentiometric surface of the Floridan Aquifer in selected well fields, west-central Florida, September 1977

The water table in the surficial aquifer and the potentiometric surface of the Floridan aquifer in a 1,200 square-mile area in west-central Florida are mapped semiannually by the U.S. Geological Survey. Maps are prepared on the basis of water levels measured in wells each May to coincide with seasonal low levels; and in September, when levels are high. The mapped area for this report contains nine producing wells fields which supplied 76.2 million gallons on September 21, 1977, to municipalities in the Tampa Bay area. The effect of localized withdrawal of groundwater from the Floridan aquifer is shown on the maps as cones of depression in both the potentiometric surface and water table. In September, water levels in observation wells in the Floridan aquifer were above those measured in May. These increases ranged from about 1 foot at the Eldridge-Wilde well field to about 25 feet at the Sun City well field. (Woodard-USGS)

Open-File Report↗
USGS1978

Water table in the surficial aquifer and potentiometric surface of the Floridan Aquifer in selected well fields, west-central Florida, May 1978

The water table in the surficial aquifer and the potentiometric surface of the Floridan aquifer in a 1,200-square-mile area in west-central Florida are mapped semiannually by the U.S. Geological Survey. Maps are prepared showing water levels measured in wells each May to coincide with seasonal low levels, and each September to coincide with seasonal high levels. The mapped area shows 11 well fields which supplied 144.0 million gallons to municipalities on May 16, 1978. The water is withdrawn from the Floridan aquifer, the major aquifer in Florida. The effect of localized withdrawal of ground water is shown on the maps as depressions in both the potentiometric and water-table surfaces. Water levels were generally lower in May 1978 than in September 1977 because of seasonal rainfall. The maximum decrease determined was more than 17 feet at Sun City well field. Water levels in May 1978 were generally higher than in May 1977 because of heavy rainfall in early May. However, water levels in well fields with significant increases in pumpage were lower.

Florida↗
USGS1978

Hydrogeologic factors affecting the availability and quality of ground water in the Temple Terrace area, Hillsborough County, Florida

Ground water occurs in two aquifers in the Temple Terrace area of Hillsborough County, Fla. The lower one is the artesian Floridan aquifer; the upper is the water-table aquifer. The Floridan aquifer is a thick sequence of limestone and dolomite layers which include several permeable zones that generally are treated as a single hydrologic unit. The top of the Tampa Limestone is considered to be the top of the Floridan in the Temple Terrace area. The public supply wells of the city tap the Tampa Limestone and the underlying Suwannee Limestone, in the upper part of the Floridan. The general direction of ground-water movement in the Floridan aquifer is from north to south, but within the city the direction of movement is from northeast to southwest. The quantity of water moving southwest through a 1.8 mile section of the aquifer is about 2.7 million gallons per day. Ample supplies of water in a cavernous limestone, considered to be the most productive water-yielding zone in the aquifer, are available for additional development from the Floridan aquifer. Water-quality data are included also. (Woodard-USGS)

Florida↗
USGS1978

Potentiometric surface of Floridan aquifer, Southwest Florida Water Management District and adjacent areas, September 1977

A potentiometric-surface map of the Southwest Florida Water Management District depicts the annual high water-level period. Potentiometric levels increased 15 to 30 feet between May 1977 and September 1977 in the citrus and farming sections of southeastern Hillsborough, northern Hardee, and southwestern Polk Counties. These areas are widely affected by pumpage for irrigation and have the greatest range in water-level fluctuations between the low and high water-level periods. Water-level rises in coastal, northern, and southern areas of the Water Management District ranged from 0 to 15 feet. (Woodard-USGS)

Florida↗
USGS1977

Water table in the surficial aquifer and potentiometric surface of the Floridan Aquifer in selected well fields, west-central Florida, May 1976

The water table in the surficial aquifer (sand) and the potentiometric surface of the Floridan aquifer (limestone) in a 1,200-square-mile area in west-central Florida are mapped semiannually by the U.S. Geological Survey. Maps are prepared each May and September to coincide with seasonal low and high ground-water levels. The mapped area contains nine producing well fields which supplied 92.8 million gallons on May 12, 1976 to municipalities along the Gulf Coast. This pumpage came from the Floridan aquifer, the major aquifer in the State of Florida. The effect of well-field withdrawals is shown on the maps as cones of depression in both the potentiometric and water-table surfaces. The May 1976 maps indicate that water levels have declined below sea level in some areas. The decline results from reduced recharge during the dry spring combined with an increase in pumpage for lawn irrigation.

Open-File Report↗
USGS1977

Water table in the surficial aquifer and potentiometric surface of the Floridan Aquifer in selected well fields, west-central Florida, September 1976

The water table in the surficial aquifer and the potentiometric surface of the Florida aquifer in a 1200 square-mile area in west-central Florida are mapped semiannually by the U. S. Geological Survey. Maps are prepared on the basis of water levels measured in wells each May to coincide with seasonal low levels, and in September, when levels are high. The mapped area contains nine producing well fields which supplied 67.2 million gallons on September 8, 1976, to municipalities along the Gulf Coast. The water is from the Floridan aquifer, the major aquifer in Florida. The effect of localized withdrawal of ground water is shown on the maps as cones of depression in both the potentiometric and water-table surfaces. The September 1976 maps show the seasonal rise in water levels from the low levels of the previous May.

Open-File Report↗