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R.K. Krulikas

Publications and source records attributed to R.K. Krulikas.

4 recordsLinked to original sources
USGS1995

Recharge to the surficial aquifer system in Lee and Hendry counties, Florida

Protection of ground-water recharge areas against contamination is of great interest in Florida, a State whose population depends heavily on ground water and that is experiencing rapid growth. The Florida Legislature is considering implementation of a tax incentive program to owners of high-rate recharge lands that remain undeveloped. High-rate recharge was arbitrarily set at 10 or more inches per year. The U.S. Geological Survey, in cooperation with the South Florida Water Management District, conducted a study to investigate the efficacy of several methods for estimating recharge to the surficial aquifer system in southwestern Florida and to map recharge at a scale of 1:100,000. Four maps were constructed at a scale of 1:100,000 for Lee and Hendry Counties, depicting the configuration of the water table of the surficial aquifer system, direction of ground-water flow, general soil characteristics, and recharge rates. Point recharge rates calculated for 25 sites in Lee County from comparisons of chloride concentrations in precipitation and in water from the surficial aquifer system ranged from 0.6 to 9.0 inches per year. Local recharge rates estimated by increases in flow along theoretical flow tubes in the surficial aquifer system were 8.0 inches per year in a part of Lee County and 8.2 inches per year in a part of Hendry County. Information on oxygen isotopes in precipitation and water from the surficial aquifer system was used to verify that the source of chlorides in the aquifer system was from precipitation rather than upward leakage of saline water. Soil maps and general topographic and hydrologic considerations were used with calculated point and local recharge rates to regionalize rates throughout Lee and Hendry Counties. The areas of greatest recharge were found in soils of flatwoods and sloughs, which were assigned estimated recharge rates of 0 to 10 inches per year. Soils of swamps and sloughs were assigned values of 0 to 3.0 inches per year; soils of tidal areas and barrier islands, soils of the Everglades, and soils of sloughs and freshwater marshes were assigned values of 0 to 2.0 inches per year; lastly, soils of manmade areas were assigned values of 0.5 to 1.5 inches per year. Small isolated areas of high-rate recharge (greater than 10 inches per year) might exist in Lee and Hendry Counties, but the maximum rate calculated in this study was 9.0 inches per year. Despite low natural recharge rates, lowering of the water table through pumping or canalization could create a potential for induced recharge in excess of 10 inches per year in parts of Lee and Hendry Counties.

Water-Resources Investigations Report↗
USGS1986

Hydrologic appraisal of the Pine Barrens, Suffolk County, New York

The groundwater resources of the Pine Barrens, in southeastern Suffolk County, were appraised during 1982-83 for their potential for use as a supply of potable water. The study area encompasses approximately 50 square miles. The Precambrian bedrock is overlain by Cretaceous, Pleistocene, and Holocene deposits. The surficial material consists of morainal and outwash deposits overlain by recent beach and marsh deposits. The groundwater reservoir consists of three aquifers--the Lloyd and the Magothy of Cretaceous age and the upper glacial of Pleistocene age. The water is generally of suitable quality for drinking and most other uses except in several localized spots where point-source contamination has been documented. Precipitation is the sole source of recharge. Average annual precipitation recorded in the area during 1943-82 was 43 inches, about half of which reaches the groundwater reservoir. Overland runoff is estimated to be 0.5 inches per year, and evapotranspiration 23 inches per year. Total public water-supply withdrawal in the area in 1982 is estimated to have been 9.09 million gallons per day (Mgal/d). The upper glacial aquifer is the major source of public water; pumpage in 1982 was 7.88 Mgal/d; pumpage from the Magothy was 1.02 Mgal/d, and pumpage from the Lloyd aquifer was 0.19 Mgal/d. Stream discharge is measured periodically at 17 streamflow measurement sites on the 11 streams in the Pine Barrens. (USGS)

Water-Resources Investigations Report↗
USGS1983

Geologic reconnaissance of an extensive clay unit in north-central Suffolk County, Long Island, New York

Recent geologic data indicate an extensive lacustrine clay unit within the glacial deposits in the area between the Harbor Hill and Ronkonkoma moraines in north-central Suffolk County, New York. The unit, locally known as the ' Smithtown clay unit ' (informal usage), is an integral part of the glacial aquifer in this area. The clay occurs at depths varying from 90 ft above to 150 ft below National Geodetic Vertical Datum of 1929 (NGVD) and attains a maximum thickness of 170 ft in the northern part of the Town of Smithtown. Its upper surface is mostly above NGVD and reaches a maximum altitude of 90 ft in the Town of Huntington. The unit is predominantly clay but locally contains lenses of sand, silt, and gravel. The upper part of the clay is generally light to dark brown; the lower part is light gray, which is characteristics of other clays in the glacial aquifer. (USGS)

Water-Resources Investigations Report↗