Publications

Arkansas experienced wide extremes in climate variability during the period of 2005 to 2010, recording the largest annual precipitation ever recorded in the State (100.05 inches) in 2009. Many weather stations across the State reported between 80 to 90 inches of rainfall in 2009. For comparison, the average annual precipitation in Little Rock, Arkansas, for the period 1878 to 2010 was 47.1 inches.

Water-level fluctuations in wells completed in the Mississippi River Valley alluvial aquifer in eastern Arkansas were compared to variability in annual precipitation, an indicator of climate variability. The wettest year on record in Little Rock, Arkansas, occurred in 2009 with 81.79 inches of precipitation compared to an average of 47.1 inches per year. In contrast, 2005 and 2010 were the 7th and

Blowing Spring Cave in northwestern Arkansas is representative of cave systems in the karst of the Ozark Plateaus, and stable isotopes of water (δ18O and δ2H) and inorganic carbon (δ13C) were used to quantify soil-water, bedrock-matrix water, and precipitation contributions to cave-spring flow during storm events to understand controls on cave water quality. Water samples from recharge-zone soils

Lake Maumelle, located in central Arkansas northwest of the cities of Little Rock and North Little Rock, is one of two principal drinking-water supplies for the Little Rock, and North Little Rock, Arkansas, metropolitan areas. Lake Maumelle and the Maumelle River (its primary tributary) are more pristine than most other reservoirs and streams in the region with 80 percent of the land area in the e

Dissolved oxygen (DO) concentrations in lowland streams are naturally lower than those in upland streams; however, in some regions where monitoring data are lacking, DO criteria originally established for upland streams have been applied to lowland streams. This study investigated the DO concentrations at which fish and invertebrate assemblages at 35 sites located on lowland streams in southwester

Predictive equations were developed for 19 ecologically relevant streamflow characteristics within five major groups of flow variables (magnitude, ratio, frequency, variability, and date) for use in the Tennessee and Cumberland River basins using stepbackward regression. Basin characteristics explain 50% or more of the variation for 12 of the 19 equations. Independent variables identified through

The Mississippi Embayment Regional Aquifer Study groundwater-flow model was used to simulate the potential effects on future groundwater withdrawals at five powerplant sites-Gleason, Weakley County, Tennessee; Tenaska, Haywood County, Tennessee; Jackson, Madison County, Tennessee; Southaven, DeSoto County, Mississippi; and Magnolia, Benton County, Mississippi. The scenario used in the simulation c

In 2005, about 30.6 million gallons per day (Mgal/d) of water was withdrawn in Beauregard Parish, Louisiana, including about 30.4 Mgal/d from groundwater sources and 0.1 Mgal/d from surface water sources. Industrial use, primarily for wood products, accounted for about 72 percent (22.0 Mgal/d) of the total water withdrawn. Other categories of use included public supply, rural domestic, livestock,

In 2005, approximately 29.2 million gallons per day (Mgal/d) of water were withdrawn in Allen Parish, Louisiana, including about 26.8 Mgal/d from groundwater sources and 2.45 Mgal/d from surface-water sources. Rice irrigation accounted for 74 percent (21.7 Mgal/d) of the total water withdrawn. Other categories of use included public supply, industrial, rural domestic, livestock, general irrigation

In 2005, about 6.67 million gallons per day (Mgal/d) of water were withdrawn in Vernon Parish, Louisiana, including about 6.46 Mgal/d from groundwater sources and 0.21 Mgal/d from surface-water sources. Public-supply use accounted for about 76 percent (5.06 Mgal/d) of the total water withdrawn. Other categories of use included rural domestic, livestock, general irrigation, and aquaculture. Based o

Stream hydrology is foundational to aquatic ecosystems and has been shown to be a structuring element for fish and invertebrates. The relations among urbanization, hydraulics, and invertebrate communities were investigated by the U.S. Geological Survey, National Water-Quality Assessment Program by using measures of stream hydraulics in two areas of the United States. Specifically, the hypothesis t

The Mississippi River-Gulf Outlet navigation channel (MRGO) was constructed in the early 1960s to provide a safer and shorter route between the Gulf of Mexico and the Port of New Orleans for deep-draft, ocean-going vessels and to promote the economic development of the Port of New Orleans. In 2006, the U.S. Army Corps of Engineers developed a plan to de-authorize the MRGO. The plan called for a ro