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A. H. Ludwig

Publications and source records attributed to A. H. Ludwig.

15 recordsLinked to original sources
USGS1990

Ground-water resources of the upper White River basin in Arkansas

The upper White River basin in Arkansas lies almost entirely within the Ozark Plateaus physiographic province, which consists of deeply dissected plateaus underlain by limestone, shale, and dolomite. Significant water-yielding units within the upper White River basin include the Eminence and Potosi Dolomites, the Roubidou Formation, the Gasconade Dolomite and the Van Buren Formation, outcrops of undifferentiated Paleozoic rocks, the Nacatoch Sand, and quaternary deposits. Water in the Quaternary deposits is the most heavily used, but areally, other units are significant sources of groundwater for domestic and rural use. The quality of groundwater withdrawn from the various units generally is suitable for most uses, although groundwater in the study area is typically very hard. Iron concentrations commonly exceed allowable limits. Yields from the different water-yielding units are highly variable. The Eminence and Potosi Dolomites are known to yield as much as 230 gal/min. Nearer the surface, the Gunter Sandstone Member of the Van Buren Formation yields as much as 500 gal/min. Above the Gunter Sandstone, the Roubidoux Formation yields as much as 450 gal/min to wells. In contrast to the high yields from these deeper units , the outcrops of Paleozoic rocks commonly yield less than 10 gal/min. The Quaternary deposits yield as much as 2,500 gal/min of very hard water. Elevated nitrate concentrations that exceed U.S. Environmental Protection Agency primary drinking-water standards occur in Marion County. In addition, saline water is present in the Quaternary deposits near Bald Knob and Cord, Arkansas. (USGS)

Open-File Report↗
USGS1990

Ground-water resources of the Arkansas River basin in Arkansas

The Arkansas River basin in Arkansas lies almost entirely within the Interior Highlands physiographic division. The Interior Highlands consist of hilly to mountainous terrain underlain by sandstone, shale, limestone, and dolomite. That part of the basin southeast of Little Rock lies within the Gulf Coastal Plain and is characterized by flat to hilly topography. Significant water-yielding units within the Arkansas River basin include subsurface Paleozoic units such as the Eminence and Potosi Dolomites, the Gasconade Dolomite, and the Van Buren Formations, and Roubidoux Formation as well as outcrops of Paleozoic rocks, the Sparta Sand, and Quaternary deposits. The quality of groundwater withdrawn from the various aquifers in the study area is generally suitable for most uses, although commonly very hard and highly mineralized. Only the Sparta Sand yields a soft, less mineralized water. Yields from the different water-bearing units are highly variable. Several of the subsurface Paleozoic rocks rarely yield more than 10 gal/min. In the Coastal Plain, the Sparta Sand and the Quaternary deposits yield as much as 2,000 and 2,500 gal/min, respectively. Several studies have indicated substantial bacterial contamination of both wells and springs in this part of the study area. Also, nitrate concentrations that exceed U.S. Environmental Protection Agency primary drinking water standards occur in some areas. (USGS)

Open-File Report↗
USGS1990

Simulation of ground-water flow in the Mississippi River Valley alluvial aquifer in eastern Arkansas

The U.S Geological Survey has developed and calibrated a digital model of the flow system in the alluvial aquifer as part of a multiagency Eastern Arkansas Region Comprehensive Study being conducted by the U. S. Army Corps of Engineers. Other cooperating agencies include the U.S. Soil Conservation Service, the Arkansas Soil and Water Conservation Commission, and the University of Arkansas. The study was prompted by the growing concern about significant water level declines in the Mississippi River Valley alluvial aquifer north of the Arkansas River in eastern Arkansas. The declines are a result of large groundwater withdrawals, mainly for irrigation. After calibration, the flow model was used to simulate the effects of projected groundwater pumpage through the year 2050, based on estimates made by the U.S. Soil Conservation Service for pumpage scenarios with and without water conservation measures. Simulations of projected pumpage indicated that by the year 2050 water level declines would reduce the saturated thickness of the aquifer to less than 20 ft in large areas of eastern Arkansas. More than 26% of the active cells in the scenario without conservation had saturated thicknesses of 20 ft or less and mroe than 16% in the scenario with conservation. The principal areas where the saturated thickness is expected to reach these critical levels are in the Grand Prairie region and in two areas on the east and west sides of Crowleys Ridge. (USGS)

Water-Resources Investigations Report↗
USGS1980

Methods and applications of digital-model simulation of the Red River alluvial aquifer: Shreveport to the mouth of the Black River, Louisiana

The Red River Waterways Project provides for the construction of five locks and dams on the Red River from the Mississippi River to Shreveport, La. The methodology used by the U.S. Geological Survey in studying the effects of the navigation pools on the ground-water-flow regime involved digital modeling of steady- and nonsteady-state conditions. The steady-state model, GWFLOW, computes the head response in an aquifer due to various boundary conditions. The nonsteady-state model, SUPERMOCK, was designed to simulate transient stress and response in an alluvial-flow system. In addition to the simulation models several computer programs were developed during the study to aid in the preparation of field data for input to the models and in the calibration of the models. Calibration techniques unique to each of the models were developed for the investigation. (USGS)

Louisiana↗
USGS1979

Preconstruction and postconstruction ground-water levels, Lock and Dam 1, Red River Valley, Louisiana

Proposed construction of a series of locks and dams in the Red River in Louisiana will cause a permanent increase in average river stage. The potentiometric surface of the shallow alluvial aquifer and the water table in the fine-grained material confining the aquifer will be affected. The purpose of this study, using digital-modeling techniques, was to predict the average postconstruction potentiometric surface (steady state) and the water table (nonsteady state) so that potential effects of the water-level changes could be evaluated. Plans for Lock and Dam 1 at mile 44 (kilometer 71) above the mouth of the Red River call for a pool elevation of 40 feet (12.2 meters) and will cause an average increase in river stage of 9 feet (2.7 meters). As a result, ground-water levels will be raised 1 foot (0.3 meter) or more within 4 miles (6.4 kilometers) of the river. The potentiometric surface may be near land surface in low-lying areas, and above land surface along the course of drainage features near the dam. The magnitude of ground-water-level fluctuations near the river will be reduced.

Louisiana↗
USGS1979

Preconstruction and postconstruction ground-water levels, Lock and Dam 2, Red River Valley, Louisiana

Proposed construction of a series of locks and dams in the Red River in Louisiana will cause a permanent increase in average river stage. The potentiometric surface of the shallow alluvial aquifer and the water table in the fine-grained material confining the aquifer will be affected. The purpose of this study using digital-modeling techniques, was to predict the average postconstruction potentiometric surface (steady state) and the water table (nonsteady state) so that potential effects of the water-level changes could be evaluated. Plans for lock and dam 2 at mile 87 (kilometer 140) above the mouth of the Red River call for a pool elevation of 58 feet (17.7 meters) and will cause an average increase in river stage of 12.5 feet (3.8 meters). As a result, ground-water levels will be raised 1 foot (0.3 meter) or more within 4 miles (6.4 kilometers) of the river and will be near land surface in low areas. The potentiometric surface may be as much as 1 to 2 feet (0.3 to 0.6 meter) above land surface south of Latanier along Chatlin Lake Canal and south of the Annandale area of Alexandria. The magnitude of ground-water-level fluctuations near the river will be reduced.

Louisiana↗
USGS1979

Preconstruction and postconstruction ground-water levels, Lock and Dam 3, Red River Valley, Louisiana

Proposed construction of a series of locks and dams in the Red River in Louisiana will cause a permanent increase in average river stage. The potentiometric surface of the shallow alluvial aquifer and the water table in the fine-grained material confining the aquifer will be affected. The purpose of this study, using digital-modeling techniques, was to predict the average postconstruction potentiometric surface (steady state) and the water table (nonsteady state) so that potential effects of the water-level changes could be evaluated. Plans for lock and dam 3 at realined mile 111 (kilometer 179) above the mouth of the Red River call for a pool elevation of 87 feet (27 meters) and will cause an average increase in river stage ranging from 21 to 3.5 feet (l.4 to 1.1 meters). As a result, ground-water levels will be raised to near land surface in low areas east of the river from the damsite to Aloha and in a 0.5-mile (0.8-kilometer) strip along the west side extending 9 miles (14 kilometers) above the dam. The potentiometric surface may be above land surface locally near the dam. The magnitude of ground-water-level fluctuations near the river will be reduced to less than half the preconstruction range.

Louisiana↗
USGS1979

Preconstruction and postconstruction ground-water levels, Lock and Dam 4, Red River Valley, Louisiana

Proposed construction of a series of locks and dams in the Red River in Louisiana will cause a permanent increase in average river stage. The potentiometric surface of the shallow alluvial aquifer and the water table in the fine-grained material confining the aquifer will be affected. The purpose of this study, using digital-modeling techniques, was to predict the average postconstruction potentiometric surface (steady state) and the water table (nonsteady state) so that potential effects of the water-level changes could be evaluated. Plans for lock and dam 4 at realined mile 154 (kilometer 250) above the mouth of the Red River call for a pool elevation of 115 feet (35 meters) and will cause an average increase in river stage ranging from 24 to 4.5 feet (7 to 1.4 meters). As a result, ground-water levels will be raised 1 foot (0.3 meter) or more between the Red River and Bayou Pierre from the dam to Coushatta , and below Campti, east of the river. The potentiometric surface may be at or near land surface in low areas between the Red River and Bayou Pierre, and above land surface locally upstream from the dam. The magnitude of ground-water-level fluctuations near the river will be reduced to less than half the present range.

Louisiana↗
USGS1979

Preconstruction and postconstruction ground-water levels, Lock and Dam 5 and 6, Red River Valley, Louisiana

Proposed construction of a series of locks and dams in the Red River in Louisiana will cause a permanent increase in average river stage. The potentiometric surface of the shallow alluvial aquifer and the water table in the fine-grained material confining the aquifer will be affected. The purpose of this study, using digital-modeling techniques, was to predict the average postconstruction potentiometric surface (steady state) and the water table (nonsteady state) so that potential effects of the water-level changes could be evaluated. Plans for lock and dam 5 at mile 243 (kilometer 390) above the mouth of the Red River call for a pool elevation of 145 feet (44 meters) and will cause an average increase in river stage of 23 feet (7.0 meters). As a result, ground-water levels in the pool area will be raised to near land surface in much of the area between the river and Bayou Pierre and as much as 2 miles (3.2 kilometers) east of the river from the dam upstream to realined mile 220 (kilometer 350). Areas of Barksdale Air Force Base where levels are now near land surface would be enlarged and extend downstream along Flat River to near Curtis. The potentiometric surface may be above land surface near Howard, Anderson Island, and Dixie Gardens. (Woodard-USGS)

Louisiana↗
USGS1979

Water-resources appraisal of the south-Arkansas lignite area

The feasibility of developing lignite resources in south-central Arkansas is an important question at the present time (1978). Part of the concern is related to the possible impacts that mining and processing of lignite will have on water resources. Not only will the disturbance caused by excavating affect the quantity and quality of surface and ground water but, the mining, processing, and conversion processes will require the use and consumption of significant quantities of water. In order to assess the magnitude of the effects of strip mining upon both surface and ground water, baseline conditions (hydrologic conditions in the area prior to mining) must be well defined. A thorough data file and literature search was made so that baseline conditions in the area could be defined. In addition, data-collection networks have been established for the collection of quantitative and qualitative information on streamflow and water levels in the aquifers. Data collected to date at these sites are included in the report. Collection of data at these sites will continue through at least September 1979. Information presented in this report can be used to estimate the quantities of water available for use and the possible effects of mining and associated dewatering on water resources.

Arkansas↗
USGS1974

Quality of water in the Red River alluvial aquifer, Shreveport, to the mouth of the Black River, Louisiana

Chemical analyses of water samples from 296 wells in the Red River alluvial aquifer indicate that the ground water in the valley is generally hard (more than 120 milligrams per liter) and has a high iron concentration (greater than 6,000 micrograms per liter). The predominant ions found in the water were calcium and bicarbonate. However, in places in the vicinity of Natchitoches, saline water, probably from underlying formations, has infiltrated the aquifer and sodium and chloride are the principal constituents.

Louisiana↗