Search USGS⌕ Search

SEARCH · Search USGS

Results for “Special Report”

Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 73 records · Page 4Linked to original sources
USGS2019

Genetic and morphological differences between water chestnut (Myrtales: Lythraceae: Trapa) populations in the northeastern United States, Japan, and South Africa

This Special Report (SR) outlines preliminary work conducted under the Aquatic Plant Control Research Program (APCRP) to investigate genetic and morphological differences of Trapa taxa (water chestnut) in the Northeastern (NE) US. Comparisons of morphological characteristics and genetics were made between Trapa populations from the native region of Eurasia and Africa versus the NE US. Unpublished data suggests a new introduction of Trapa (herein referred to as Trapa sp.) has occurred in the Commonwealth of Virginia, US with unknown biology and life history. Observations of morphological and phenological characteristics of this potential new taxon of Trapa differ from those typically found with naturalized Trapa natans reported in the NE US. A better understanding of the biology and ecology of Trapa sp. is warranted to identify control strategies that would benefit water resource managers tasked with management of water chestnut.

Technical Report↗
USGS2018

Water use in Louisiana, 2015

In 2015, approximately 8,720 million gallons per day (Mgal/d) of water was withdrawn from groundwater and surface-water sources in Louisiana, a 2.6 percent increase from 2010. Total groundwater withdrawals were about 1,750 Mgal/d, an increase of 12 percent from 2010, and total surface-water withdrawals were about 6,970 Mgal/d, an increase of 0.44 percent from 2010 to 2015. Total water withdrawals, in Mgal/d, in 2015 for the various categories of use were as follows: public supply—715, industry—2,155, power generation—4,265, rural domestic—39, livestock—6, rice irrigation—825, general irrigation—225, and aquaculture—490. From 2010 to 2015, Louisiana’s total withdrawals for public supply decreased by 3.4 percent, industry increased by 5.7 percent, power generation decreased by 3.9 percent, rural domestic decreased by 4.1 percent, livestock decreased by 21 percent, rice irrigation increased by 20 percent, general irrigation decreased by 6.0 percent, and aquaculture increased by 58 percent. About 48 percent (approximately 850 Mgal/d) of all groundwater withdrawn was from the Chicot aquifer system and 22 percent (approximately 385 Mgal/d) was withdrawn from the Mississippi River alluvial aquifer. Since 2010, withdrawals from the Chicot aquifer system increased by 30 percent and withdrawals from the Mississippi River alluvial aquifer decreased by 2.9 percent. About 70 percent (4,905 Mgal/d) of all surface water withdrawn was from the Mississippi River mainstem. This value represents a 1.1-percent decrease in withdrawals from 2010 to 2015. All water-withdrawal and water-use data presented in this report should be considered estimates. Because of rounding, totals and percentages presented in the tables, figures, and text in the report may differ slightly from totals or percentages calculated individually

Louisiana↗
USGS1978

Drought in California; water resources data for 1977

The 2-year dry period 1976-77 was the most severe drought in northern California 's history, and the quantity and quality of all water-supply sources in the State were affected. This report contains special water-resources data collected by the Geological Survey during 1977. These data include: streamflow at 11 selected stations, comparing the 1977 mean monthly and yearly flow to the period-of-record medians; base-flow measurements at 189 selected sites; water quality at 131 selected sites; ground-water levels in wells and river stages along a 158-mile reach of the Sacramento River; and, finally, graphs showing the effect of tidal action on suspended-sediment concentration at the stream-gaging station on the Sacramento River at Sacramento. (Woodard-USGS)

Open-File Report↗
USGS1951

Preliminary report on the geology and ground-water supply of the Newark, New Jersey, area

In the Newark area, ground water is used chiefly for industrial cooling, air-conditioning, general processing, and for sanitary purposes. A small amount is used in the manufacture of beverages. Total ground-water pumpage in Newark is estimated at not less than 20,000,000 gallons daily. The Newark area is underlain by formations of Recent, Pleistocene and Triassic age, and the geology and hydrologic properties of these formations are discussed. Attention is called to the important influence of a buried valley in the rock floor beneath the Newark area on the yield of wells located within it. Data on the fluctuation of the water levels and the variation in pumpage are presented, and their significance discussed. The results of a pumping test made during the investigation were inconclusive. The beneficial results of artificially recharging the aquifers in one part of the area are described. The intrusion of salt water into certain parts of the ground-water body is described and graphically portrayed by a map showing the chloride concentration of the ground water in various parts of the City. Insofar as available data permit, the chemical quality of the ground water is discussed and records are given of the ground-water temperatures in various parts of the City. There has been marked lowering of the water table in the eastern part of the area, accompanied by salt water intrusion, indicating that the safe yield of the formations in this part of Newark has probably been exceeded. It is recommended that the study of the ground-water resources of this area be continued, and that artificial recharging of the aquifers be increased over as wide an area as possible.

New Jersey↗
USGS1958

Ground-water resources in the tri-state region adjacent to the Lower Delaware River

The purpose of this report is to appraise and evaluate the groundwater resources of a tri-state region adjacent to the lower Delaware River that is centered around Philadelphia, Pa., and Camden, N. J., and includes Wilmington, Del., and Trenton, N.J. Specifically, the region includes New Castle County, Del.; Burlington, Camden, Gloucester, Mercer, and Salem Counties in New Jersey; and Bucks, Chester, Delaware, Montgomery, and Philadelphia Counties in Pennsylvania. The peculiar advantages of ground water, such as its availability in many places without the necessity for expensive pipelines and its relatively uniform temperature and quality, make it an especially valuable resource in an industrial area. Large, readily available supplies of good, fresh water have contributed substantially to the recent rapid industrial growth of the lower Delaware River basin and will be vital to its continued prosperity. The major part of these supplies is drawn from the streams passing through the region, but very large quantities of ground water also are used. The region is divided almost equally by the Fall Line, which extends in a southwesterly direction along the general course of the Delaware River from Trenton, N.J., to Wilmington, Del., and beyond. Northwest of the Fall Line is a region of consolidated rocks in which ground water occurs mainly in cracks, crevices, and openings created or enlarged by weathering. The capacity of the various geologic formations to yield water depends largely upon the degree to which they have been fractured and weathered. The yield of individual wells in this part of the region is generally small to moderate and not readily predictable. Ground water in this part of the region is generally low in dissolved minerals and suitable for many uses without treatment. Southeast of the Fall Line lie the unconsolidated rocks of the Coastal Plain. Ground water occurs in these rocks largely in the pore spaces between the individual mineral grains. The major formations and the principal aquifers are rather uniform in their water-bearing characteristics over large areas. The yield of individual wells is moderate to very large and may be predicted with a reasonable degree of assurance. Sufficient quantities of ground water are available in most places for all ordinary purposes. The chemical quality of the ground water from the Coastal Plain aquifers is generally acceptable for most uses, but objectionable quantities of iron or other minerals are found in some places, and some waters have a low pH and are corrosive. More than 40 distinct geologic formations occur in the region. They range in age from Precambrian to Recent. Nearly all will yield some water to wells. However, only about a dozen yield water freely enough to be considered major aquifers. Of these, the sands of the Raritan and Magothy formations have been developed most intensively, and the Cohansey sand appears to have the greatest capacity for additional development. The present withdrawal of ground water in the region is estimated to average more than 200 mgd, of which more than half is drawn from the aquifers in the Raritan and Magothy formations. It is estimated that additional supplies of ground water, aggregating more than 1 billion gallons a day, can be developed within the region. Furthermore, substantial additional quantities can be developed outside the region for use within it if the need should ever arise. Induced recharge from the Delaware River supplies a substantial portion of the total water drawn from the Raritan and Magothy formations. In some areas, the quality of the water from these aquifers is approaching that of the river. Increased withdrawals of water from wells along the river will tend to increase induced recharge. Thus, the maintenance of a good quality of water in the river, which is desirable for many other reasons, is imperative if the quality of the ground-water supply is to be maintained. The proposed deepening of the Delaware River channel from Philadelphia to Trenton will greatly increase the opportunity for the interchange of water between the river and the adjacent aquifers. Whether this will be beneficial or detrimental to the ground-water supplies will depend upon the quality of the water in that reach of the river. If an acceptable quality of river water is maintained, the groundwater resources of the region will be augmented. If salt water from the ocean or excessive contamination from other sources should render the river water undesirable as a source of recharge, actual and potential ground-water supplies aggregating about 250 mgd would be endangered. The danger of salt-water encroachment into the aquifers normally yielding fresh water may limit the optimum yield of some of the most important aquifers in the region. Encroachment may come either from salt water in the surface-water bodies of the region or from parts of the aquifers, normally containing salt water. The protection of ground-water supplies against salt-water encroachment can be maintained only by constant vigilance, careful distribution of the pumping from the aquifers, regular sampling of outpost wells in exposed localities, and adjustment of rates of pumping in the light of changing conditions. The maximum beneficial utilization of the ground-water resources cannot be accomplished in haphazard fashion. It must be planned and controlled on the basis of sound, current information about the hydrology of the various aquifers. Continued and, in some areas, intensified investigations of the ground-water resources of the region should form the basis for such planning and control.

New Jersey, Pennsylvania, Delaware↗
USGS1936

Supplementary report on the ground-water supplies of the Atlantic City region

This report is the second progress report on the ground-water investigations in the Atlantic City region. Many important problems still remain to be solved, however, and it is in no sense a final report. The report covers the area immediately surrounding Atlantic City, extending from Brigantine to Sea Isle City along the coast and from Absecon to Somers Point on the mainland. In addition to this, a few data are presented bearing on the area along the coast as far south as Wildwood. The area lies in the southern part of the New Jersey Coastal Plain, and the water-bearing formations considered are all unconsolidated and of Miocene or more recent age. The major formations in the region dip gently toward the ocean and possibly extend out under the ocean to the edge of the Continental Shelf, about 100 miles from Atlantic City. The principal ground-water supplies in the area are derived from the so-called "800-foot sand," a member of the Kirkwood formation, and from the overlying Cohansey sands. The 800-foot sand is of wide extent and apparently fairly uniform. The Cohansey sands, on the other hand, cover a wide area but are by no means uniform. At the Atlantic City Water Works two Cohansey sands are recognized-the so-called "100-foot" and "200-foot" sands. Neither of these sands can be differentiated from the other sands of the Cohansey formation over a distance greater than 4 or 5 miles in any direction. In addition to the supplies derived from ground water, some surface water is used at present by two of the public water supplies. The quality of the water from all the sources of supply now used is satisfactory. The total consumption of water in the region has increased gradually over the entire period of record, except for a moderate decline from 1929 to 1934. Additional water supplies can be obtained from either of two fairly large streams near the region, and possibly also from a more widespread development of the Cohansey sands. The 800-foot sand should not be counted upon as a source of additional water supply, in view of its liability to salt-water contamination. The same danger also exists in the Cohansey sands on the mainland near the shore, but farther inland it is not a serious menace to the supply from these sands The 100-foot sand at the Atlantic City Water Work has been overdeveloped since 1930, with the result that the head of the water in it has been lowered materially and salt water has been drawn into it through holes in the overlying clay beneath the nearby salt marshes. Three of the five new large-capacity wells drilled to this sand in 1930 have been temporarily or permanently abandoned on account of salt-water intrusion, and the two others will probably have to be abandoned also, unless suitable remedial measures are promptly adopted. It is recommended that the wells to the 100-foot sand be used only when needed to supply the seasonal peak demand and that consideration be given to a project to transform the tidal marshes into a fresh-water pond by means of a suitable dam in order to protect the formation from further contamination. If detailed study proves that the dam and fresh-water pond would not be economically justified, a smaller pond and an embankment and tide gates on the main stream to keep the salt water from flooding the marshes are recommended as less effective but less expensive remedial measures. In view of the experience with the 100-foot sand at the Atlantic City Water Works, it is further recommended that any additional development of the Cohansey sands be preceded by a comprehensive test-well program that will indicate not only the capacity of the sands, but the location of salt water in them and the possibility of its being drawn into existing wells or the proposed new wells. The salt-water intrusion into the 100-foot sand was effectively studied by means of driven-well points, which, it was found, could easily be driven to a depth of about 100 feet. The fact that the screen of these wells was driven with the casing and that no water was used in the drilling process made it possible to collect true samples of water from every sand encountered in them. This, in turn, made it possible to study the vertical distribution of salt water in each well. The interpretation of the vertical distribution of salt water in these wells was very helpful in arriving at a final decision as to the source of the salt water. The 200-foot sand at the Atlantic City Water Works has also been subjected to a considerably increased draft since 1930. Although there is no evidence at present that this sand has been overdeveloped, a study of its characteristics suggests that it may not be capable of yielding permanently the capacity of the present wells that tap it. Three test wells have been installed between the well field and the source from which this sand might derive salt water, and they should be sampled regularly to determine the danger of salt-water intrusion into the sand. In a landward direction this sand merges into the other Cohansey sands. It is therefore advisable that any additional development of the Cohansey sands should be undertaken so far inland that the pumping from it will not affect the present wells to the 200-foot sand and thereby increase the danger of salt-water contamination in them. At present more potable water is taken from the Atlantic City 800-foot sand than from any other source of supply for the region. This sand is the sole source for some of the smaller communities on the barrier beaches. The original static head of the water in it at Atlantic City was between 20 and 25 feet above sea level. The head has been lowered more than 50 feet over much of the region, and in parts of Atlantic City it has been lowered considerably more than 100 feet. A consideration of the principles governing the relation between salt water and fresh water in water-bearing sands indicates that the 800-foot sand probably contained salt water at a distance of 5 or 10 miles out from Atlantic City before any water was pumped from it. The evidence collected in this investigation indicates that the cone of depression created by the pumping from this sand in the Atlantic City region has probably extended inland to the intake area of the sand, the nearest part of which is probably about 40 miles from Atlantic City. If this is so, the conclusion is almost inescapable that it has also extended oceanward for a distance considerably greater than the 5 or 10 miles to the original zone of contact between the fresh and salt waters, and that salt water is probably being drawn toward the Atlantic City region through this sand. The time of its arrival will depend primarily upon the rate of pumping in the region and upon how much of the fresh water that originally lay between the region and the zone of contact must be removed before the salt water can reach the region. It may arrive in the near future if it advances in the form of a narrow tongue. On the other hand, if it advances along a broader front; so that more of the intervening fresh water must be pumped out of the formation, its arrival may be delayed for some time.

New Jersey↗
USGS2008

Validation of exposure time for discharge measurements made with two bottom-tracking acoustic doppler current profilers

Previous work by Oberg and Mueller of the U.S. Geological Survey in 2007 concluded that exposure time (total time spent sampling the flow) is a critical factor in reducing measurement uncertainty. In a subsequent paper, Oberg and Mueller validated these conclusions using one set of data to show that the effect of exposure time on the uncertainty of the measured discharge is independent of stream width, depth, and range of boat speeds. Analysis of eight StreamPro acoustic Doppler current profiler (ADCP) measurements indicate that they fall within and show a similar trend to the Rio Grande ADCP data previously reported. Four special validation measurements were made for the purpose of verifying the conclusions of Oberg and Mueller regarding exposure time for Rio Grande and StreamPro ADCPs. Analysis of these measurements confirms that exposure time is a critical factor in reducing measurement uncertainty and is independent of stream width, depth, and range of boat speeds. Furthermore, it appears that the relation between measured discharge uncertainty and exposure time is similar for both Rio Grande and StreamPro ADCPs. These results are applicable to ADCPs that make use of broadband technology using bottom-tracking to obtain the boat velocity. Based on this work, a minimum of two transects should be collected with an exposure time for all transects greater than or equal to 720 seconds in order to achieve an uncertainty of ??5 percent when using bottom-tracking ADCPs. ?? 2008 IEEE.

Conference Paper↗
USGS1975

Radiometric dates from Alaska: A 1975 compilation

The following table of radiometric dates from Alaska includes published material through 1972 as well as some selected later data. The table includes 726 mineral and whole-rock dates determined by the K-Ar, Rb-Sr, fission-track U-Pb, and Pb-alpha techniques. The data are organized in alphabetical order of the 1:250,000 scale quadrangles in which the dated rocks are located. The latitude and longitude of each sample are given. In addition, each sample is located on a 1:250,000 quadrangle map by a grid system. The initial point of the grid is taken as the southwest corner of the quadrangle and the location of the sample is measured in inches east and inches north from that corner, e.g., "156E 126N" indicated 15.6 inches east and 12.6 inches north of the southwest corner of the quadrangle. Zeroes in the location columns for some dates indicate that accurate locations are not available. Rock type, dating method, mineral dated, radiometric age, sample identification number, and reference are also listed where possible. Short comments, mostly geographic locality names, are given for some dates. These comments have been taken from the original references. Sample identification numbers beginning with "AA" or "BB" have been assigned arbitrarily in cases where sample numbers were not assigned in the original references. Abbreviations are explained in the appendix at the end of table 1.

Alaska↗
USGS1971

Ground-water resources: Cumberland County, New Jersey

Cumberland County is located in the Atlantic Coastal Plain physiographic province along the northeastern shore of Delaware Bay in Southwestern New Jersey. An average annual hydrologic budget was computed for Cumberland County. Water gains are: precipitation, 1,050 mgd (million gallons per day); surface-water inflow, 142 mgd; ground-water inflow negligible. Water losses are: evapotranspiration, 685 mgd; surface-water outflow, 370 mgd; ground-water outflow, 137 mgd. Unconsolidated and semiconsolidated Coastal Plain sediments, 2,500 to 4,500 feet thick, and ranging in age from Cretaceous to Holocene, consist of layers of clay, silt, sand and gravel. Aquifers composed mainly of sand and gravel occur in the Potomac Group and Raritan and Magothy Formations, the Wenonah Formation and Mount Laurel Sand, the Piney Point Formation, and the Kirkwood Formation and Cohansey Sand. Aquifers in the Potomac-Raritan-Magothy sequence contain saline water and are not currently utilized in Cumberland County. However, they may be utilized in the future for underground storage of fresh water, or possibly other uses when more is known about this aquifer system. The aquifer in the Wenonah Formation and Mount Laurel Sand is not presently utilized in Cumberland County. It is probably suitable for future development, however of wells yielding as much as 300 gpm (gallons per minute) of good quality water in the northern part of the county. The Piney Point Formation is tapped in Cumberland County by only a few wells; each of these generally yield less than 100 gpm. Additional small supplies can be developed from this aquifer. Water from this aquifer requires little or no treatment for domestic use. Two principal aquifers occur in the Kirkwood Formation and Cohansey Sand: (1) the lower Kirkwood aquifer and (2) the Cohansey-Kirkwood aquifer. Most wells tapping the lower Kirkwood aquifer yield less than 50 gpm but are capable of yielding as much as 400 gpm. Wells in the lower Kirkwood range in depth from 200 to 370 feet. The Cohansey-Kirkwood aquifer is the shallowest and most important source of ground-water in the county but is highly susceptible to surface contamination. This aquifer is highly permeable; analysis of data from two pumping tests indicates permeabilities of 1,200 and 2,700 gpm per square foot. It generally yields large supplies of water (300 to 1,200 gpm) to wells from depths of less than 180 feet. Water in the Cohansey-Kirkwood aquifer is characterized by 1mv dissolved-solids content (63 mg/l, median), low hardness (21 mg/l, median), and low pH values (5.5 pH units, median). Water use in Cumberland County varies and is highly seasonal, mainly because of increasing requirements for irrigation and the food processing industries in the county. In 1964 seasonal use ranged from 27 mgd in March to 145 mgd in August. This is much higher than withdrawals in neighboring Salem and Cape May Counties. In 1964 withdrawals in Cumberland County averaged about 51 mgd; almost all of this, 49.4 mgd, was from ground-water supplies. The total annual water use in 1964 according to type of use was: for public supply, 10.6 mgd; for industrial uses, 19.0 mgd; irrigation, 15.4 mgd; suburban, rural, residential, institutional, farm, and commercial, 5.9 mgd.

New Jersey↗
USGS1973

Geology and water resources of the Wharton Tract and the Mullica River basin in southern New Jersey

The Wharton Tract is an area of 150 square miles located in the Mullica River basin in southern New Jersey's Pine Barrens region. The tract is a relatively flat, low-lying, generally sandy area containing shallowly incised streams. The larger streams are commonly bordered by swamps. The tract was purchased by the State primarily as a water-supply preserve, but also for conservation and recreational purposes. Mean streamflow at three continuous record gaging stations in the Wharton Tract is: Mullica River near Batsto (46.1-square mile drainage area), 6 mgd (million gallons per day); Batsto River at Batsto (70.5-square mile drainage area), 81 mgd; Oswego River at Harrisville (64.0-square mile drainage area), 55 mgd. Thus mean discharge from this 180.6-sq mi (square mile) area is 202 mgd or 1.12 mgd per sq mi. Principal aquifers in the Wharton Tract and Mullic River basin are in the Kirkwood Formation of middle Miocene age, Cohansey Sand of Miocene(?) and Pliocene(?) age, and in overlying hydraulically connected deposits of Quaternary age. The Kirkwood Formation is composed of sand, silt, and clay. Diverse lithologies represent deposition in different environments such as nearshore marine, barrier bar, lagoonal, estuarine, and tidal marsh. Hydraulic characteristics of the Kirkwood in the Mullica River basin are virtually unknown. Most Kirkwood aquifers in the basin are believed to be hydraulically connected with the overlying Cohansey Sand. The Cohansey Sand is dominantly a quartz sand containing minor amounts of pebbly sand, silty sand, and interbedded clay. Almost all of the Wharton Tract and most of the Mullica River basin lie within the sandier area of the Cohansey, which contains approximately 75 percent sand beds and 25 percent silt and clay beds. Data from test drilling show that the upper 100 feet of sediments in the Wharton Tract contain about 93 percent sand beds, 3.5 percent clay beds, and 3.5 percent silt beds. The Cohansey in the Tract ranges in thickness from less than 50 feet to about 180 feet; the average thickness is about 125 feet. The Cohansey Sand is believed to be, in overall aspect, a deltaic deposit. It contains materials that were deposited locally in nearshore-marine, fluvial, estuarine, lagoonal, and beach environments. The hydraulic conductivity of Cohansey aquifer material ranges from about 90 to 250 feet per day (660 to 1,885 gallons per day per square foot) in southern New Jersey. One aquifer test in the Wharton Tract gives an average value of 130 feet per day (1,000 gallons per day per square foot). The transmissivity of the Cohansey Sand aquifer through most of the Wharton Tract is typically between 10,000 and 20,000 square feet per day (75,000 and 150,000 gallons per day per foot). Deposits of Quaternary age form a discontinuous veneer lying unconformably above the Cohansey Sand. The most important hydrologic function of most of these deposits is to absorb precipitation and transmit the water to the underlying Cohansey Sand. Thicker deposits of estuarine sand and clay of the Cape May Formation fill a channel in the underlying Cohansey Sand along the lower reaches of the Mullica River. This channel deposit is 85 feet thick near Batsto. Ground water and surface water in the Mullica River basin are low in dissolved solids, generally less than 50 mg/1 (milligrams per liter). Iron concentrations are generally high, up to 49,000 micrograms per liter (49 mg/1) in ground water and up to 7,100 micrograms per liter (7.1 mg/1) in the streams. The water is acidic as indicated by typical pH values of from 4.5 to 6.5. Color of the surface water is commonly high, ranging from 3 - 150 platinum-cobalt units. After appropriate treatment these waters are acceptable for most uses. The Wharton Tract is well situated to support the growing water needs of nearby New Jersey communities. Maximum development of water can be achieved by conjunctive use of ground and surface water. During most of the year, some water would be withdrawn either directly from streams or from adjacent wells. During periods of low flow during summer or fall water would be pumped from wells farther from the stream~. From analysis of flow-duration curves it is estimated that 70 mgd of water could be developed with minimal effect upon low flows in the half of the tract above the gaging stations on the Mullica and Batsto Rivers. The quantity available in the entire tract is greater, possibly in the order of 150 mgd. With augmentation of streamflow by pumping from ground water, it is likely that considerably more water could be safely used on a perennial basis. A possibility exists for multiple use of the water resources of the Mullica River through construction of an inexpensive tide barrier at the Garden State Parkway. This would create a fresh water lake in a State forest, park, and recreational area, which would also provide a flexible and economical water supply for much of the Atlantic coastal resort development.

New Jersey↗
USGS1968

Ground-water resources of Monmouth County, New Jersey

Monmouth County includes an area of 538 square miles in east-central New Jersey. The climate is characterized by moderate temperature, moderate humidity, and moderate precipitation. The exposed rocks in the area are chiefly sands and clays, which range in age from Late Cretaceous through Recent. The formations strike northeast-southwest and dip gently to the southeast. These rocks range in total thickness from about 500 to 1,200 feet or more and are underlain by basement rocks of late Precambrian (?) age. The principal aquifers underlying Monmouth County occur in the Raritan and Magothy Formations, the Englishtown Formation, the Wenonah Formation and Mount Laurel Sand, the Vincentown Formation, and the Kirkwood Formation. Ground water constituted about 50 percent of the total water use in 1958. The daily withdrawal of ground water was at an average rate of 21.6 mgd (million gallons per day) in 1958 and about 32 mgd in 1965 (N. J. Division of Water Policy and Supply). The water demand is expected to increase to about 133 mgd by the year 2000. An analysis of streamflow records for the period 1932 to 1950 suggests that, excluding the Raritan and Magothy Formations, the major aquifers that occur under water-table conditions in the county discharge an average of about 178 mgd to streams. The aquifers in the Raritan and Magothy Formations contribute little or no water directly to streams in Monmouth County. These aquifers have been the most productive in the county. However, because salt water has been found in the lower parts of these formations in Ocean County, further development should proceed watchfully to assure that salt water does not threaten existing supplies. Aquifers in the Raritan and Magothy Formations and the Englishtown Formation supplied 76 percent of the ground water used in 1958. These aquifers, in conjunction with the Wenonah Formation and Mount Laurel Sand of Late Cretaceous age, are capable of providing relatively large yields to wells. The average yield of 63 large-diameter wells tapping these aquifers is 580 gpm, at depths randing from 100 to 1,140 feet. In general, the concentrations of chemical constituents in water from the aquifers would not restrict the use of the water for most purposes. High concentrations of iron do occur and require treatment. The concentrations of dissolved solids in 39 to 41 samples were 160 ppm (parts per million) or less.

New Jersey↗
USGS1968

Geology and ground-water resources of Burlington County, New Jersey

Burlington County, which lies between Trenton, Atlantic City and Camden, has an area of 827 square miles. The county is in the Atlantic Coastal Plain physiographic province, has moderate temperatures and a dependable rainfall of 44 inches per year. The area is attracting new industries and additional population. Water usage is increasing with this economic growth; 26 mgd (million gallons per day) of ground water were used in 1960. The Raritan and Magothy Formations are the most prolific producers, but the Cohansey Sand and Kirkwood Formation have a great and, as yet, untapped potential. Small to moderately large supplies have been obtained from other aquifers. The maximum average potential recharge to the ground-water reservoirs is estimated to be about 790 mgd. Presently, most of it is rejected because the aquifers are essentially full. On this basis, it is believed that ground-water supplies in Burlington County are sufficient for the foreseeable future. However, well spacing must be planned to avoid local overdevelopment.

New Jersey↗