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Matthew E. Broom

Publications and source records attributed to Matthew E. Broom.

4 recordsLinked to original sources
USGS1984

A reconnaissance study of saltwater contamination in the El Dorado aquifer, Union County, Arkansas

Since 1960 chloride concentrations in the El Dorado aquifer have increased near El Dorado, Arkansas. The aquifer is a major source for municipal and industrial water supply in Union County. Greatest withdrawal occurs near El Dorado. Because of this withdrawal, the potentiometric surface at El Dorado has been lowered more than 300 feet. Geologic, hydrologic, and chemical data indicate that water from a graben south and east of El Dorado is the source of contamination from salt within the El Dorado aquifer. The data indicates that surface brines and deeper aquifers are not the sources of chloride contamination. Lowering the potentiometric surface near El Dorado has caused water to move out of the graben toward El Dorado. Estimates based on interpretation of electric logs for two wells in the graben indicate chloride equivalents may be as high as 2,500 milligrams per liter in the aquifer. Concentrations outside the graben range from 130 to 650 milligrams per liter at the west end of the graben and from 25 to 150 milligrams per liter farther west and north. (USGS)

Water-Resources Investigations Report↗
USGS1981

Alluvial aquifer of the Cache and St. Francis River basins, northeastern Arkansas

The alluvial aquifer underlies about 9,000 square miles of the study area. Well yields from the aquifer commonly are from 1,000 to 2,000 gallons per minute. Flow toward the main area of pumping stress is eastward from the Cache River and westward from the St. Francis River. The Memphis aquifer acts as a conduit through Crowleys Ridge for induced flow from the St. Francis River basin to the Cache River basn. Water use from the alluvial aquifer since the early 1900 's has been mostly for rice irrigation. Total pumpage for rice in 1978 was about 1,650 ,000 acre-feet, of which about 88 percent was pumped from the aquifer west of Crowleys Ridge. Water levels in wells west of the ridge in parts of Poinsett, Cross, and Craighead Counties in 1978 were 75 feet below land surface and declining about 2 feet per year. Digital-model analysis indicated that at the end of 1978 water was being removed from aquifer storage at the rate of 540,000 acre-feet per year, and streamflow, mostly from the Cache River and Bayou DeView, was being captured at the rate of 430,000 acre-feet per year. Projecting the 1978 pumping rate of 1,460,000 acre-feet per year, the pumping rate would have to be reduced by about 110,000 acre-feet per year by 1990 to sustain sufficient aquifer saturation for water needs through the year 2000 in all parts of Poinsett, Craighead, and Cross Counties west of Crowleys Ridge.

Arkansas, Mississippi, Missouri, Tennessee↗
USGS1979

Digital model of the Bayou Bartholomew alluvial aquifer stream system, Arkansas

A digital model of the Bayou Bartholomew aquifer-stream system in Arkansas was calibrated for the purpose of predicting hydrologic responses to stresses of water development. The simulated-time span for model calibration was from 1953 to 1970, during which time the system was stressed largely by ground- and surface-water diversions for rice irrigation. The model was calibrated by comparing groundwater-level and streamflow data with model-derived groundwater levels and streamflow. In the calibrated model, the ratio of model-derived to observed streamflows for 17 subbasins averaged 1.1; the ratios among the subbasins ranged from 0.8 to 1.6. The average deviation of the differences between model-derived and observed groundwater levels at 47 nodes was 0.2; the average among the nodes ranged from -2.3 to 10.4. The average standard deviation of the differences between the model-derived and observed groundwater levels was 3.5; the average among the nodes ranged from 0.4 to 10.5. The model will provide projections of changes in the potentiometric surface resulting from (1) changes in the rate or distribution of groundwater pumpage or (2) changes in the stage of streams and reservoirs. The model will provide only approximate projections of the streamflow.

Arkansas↗