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J. Brian Atkins

Publications and source records attributed to J. Brian Atkins.

9 recordsLinked to original sources

Water quality in the Mobile River Basin, Alabama, Georgia, Mississippi, and Tennessee, 1999-2001

This report contains the major findings of a 1999?2001 assessment of water quality in the Mobile River Basin. It is one of a series of reports by the National Water-Quality Assessment (NAWQA) Program that present major findings in 51 major river basins and aquifer systems across the Nation. In these reports, water quality is discussed in terms of local, State, and regional issues. Conditions in a particular basin or aquifer system are compared to conditions found elsewhere and to selected national benchmarks, such as those for drinking-water quality and the protection of aquatic organisms. This report is intended for individuals working with water-resource issues in Federal, State, or local agencies, universities, public interest groups, or in the private sector. The information will be useful in addressing a number of current issues, such as the effects of agricultural and urban land use on water quality, human health, drinking water, source-water protection, hypoxia and excessive growth of algae and plants, pesticide registration, and monitoring and sampling strategies. This report is also for individuals who wish to know more about the quality of streams and ground water in areas near where they live, and how that water quality compares to the quality of water in other areas across the Nation. The water-quality conditions in the Mobile River Basin summarized in this report are discussed in detail in other reports that can be accessed from the Mobile River Basin Web site (http://al.water.usgs.gov/pubs/mobl/mobl.html). Detailed technical information, data and analyses, collection and analytical methodology, models, graphs, and maps that support the findings presented in this report in addition to reports in this series from other basins can be accessed from the national NAWQA Web site (http://water.usgs.gov/nawqa).

Alabama, Georgia, Mississippi, Tennessee

Occurrence and distribution of nutrients, suspended sediment, and pesticides in the Mobile River Basin, Alabama, Georgia, Mississippi, and Tennessee, 1999-2001

The Mobile River Basin is one of more than 50 river basins and aquifer systems being investigated as part of the U.S. Geological Survey's National Water- Quality Assessment (NAWQA) Program. This basin is the sixth largest river basin in the United States and the fourth largest in terms of streamflow. The Mobile River Basin encompasses parts of Alabama, Georgia, Mississippi, and Tennessee, and almost two-thirds of the 44,0000-square-mile basin is located in Alabama. The extensive water resources of the Mobile River Basin are influenced by an array of natural and cultural factors, which impart unique and variable qualities to the streams, rivers, and aquifers and provide abundant habitat to sustain the diverse aquatic life in the basin. From January 1999 to December 2001, a study was conducted of the occurrence and distribution of nutrients, suspended sediment, and pesticides in surface water of the Mobile River Basin. Nine sampling sites were selected on the basis of land use. The nine sites included two streams draining agricultural areas, two urban streams, and five large rivers with mixed land use. Surface-water samples were collected from one to four times each month to characterize the spatial and temporal variation in nutrient and pesticide concentrations. Nutrient and suspended-sediment concentrations were highest in watersheds dominated by urban or agricultural land uses. Forty-two percent of the total phosphorus concentrations at all nine sites exceeded the U.S. Environmental Protection Agency's recommended maximum concentration of 0.1 milligram per liter. Flow-weighted mean concentrations at the Mobile River Basin sites generally were in the lower to middle percentile ranges compared with data from other NAWQA studies across the Nation. However, flow-weighted mean concentrations of ammonia, total nitrogen, orthophosphate, and total phosphorus at Bogue Chitto Creek, an agricultural watershed, ranked in the upper 20th percentile of agricultural sites sampled across the Nation as part of the NAWQA Program. Nutrient loads in the Tombigbee River were nearly twice as high compared with nutrient loads in the Alabama River. Nutrient yields were highest in Bogue Chitto Creek, Cahaba Valley Creek, and Threemile Branch because of agricultural and urban land uses in these watersheds. Of the 104 pesticides and degradation products analyzed in the stream samples, 69 were detected in one or more samples. Of the 69 detected pesticides, 51 were herbicides, 15 were insecticides, and 3 were fungicides. A relatively small number of heavily used herbicides accounted for most of the detections, including atrazine and its metabolites (deethylatrazine, 2-hydroxyatrazine, deisopropylatrazine, and deethyldeisopropylatrazine), simazine, metolachlor, tebuthiuron, prometon, diuron, and 2,4-D. Diazinon, chlorpyrifos, and carbaryl were the most frequently detected insecticides; metalaxyl was the most frequently detected fungicide in the Mobile River Basin. Concentrations of pesticides detected in surface water of the Mobile River Basin were among the highest concentrations recorded nationally by the NAWQA Program during 1991 to 2001. The three highest concentrations of atrazine detected at sites across the country were recorded at Bogue Chitto Creek; the highest concentrations of 2,4-D, imazaquin, and malathion recorded nationally were detected at Threemile Branch. Aquatic-life criteria were exceeded by concentrations of five herbicides (2,4-D, atrazine, cyanazine, diuron, and metolachlor), six insecticides (carbaryl, chlorpyrifos, diazinon, dieldrin, malathion, and p,p'-DDE), and one fungicide (chlorothalonil). Drinking-water standards were exceeded by concentrations of four herbicides (2,4-D, atrazine, cyanazine, and simazine), three insecticides (alpha- HCH, diazinon, and dieldrin), and one fungicide (chlorothalonil). The types and concentrations of pesticides found in surface water are linked to land use and to the types of pesti

Alabama, Georgia, Mississippi, Tennessee

Environmental setting and water-quality issues of the Mobile River Basin, Alabama, Georgia, Mississippi, and Tennessee

The Mobile River Basin is one of over 50 river basins and aquifer systems being investigated as part of the U.S. Geological Survey National Water-Quality Assessment (NAWQA) Program. This basin is the sixth largest river basin in the United States, and fourth largest in terms of streamflow, encompassing parts of Alabama, Georgia, Mississippi, and Tennessee. Almost two-thirds of the 44,000-square-mile basin is located in Alabama. Extensive water resources of the Mobile River Basin are influenced by an array of natural and cultural factors. These factors impart unique and variable qualities to the streams, rivers, and aquifers providing abundant habitat to sustain the diverse aquatic life in the basin. Data from Federal, State, and local agencies provide a description of the environmental setting of the Mobile River Basin. Environmental data include natural factors such as physiography, geology, soils, climate, hydrology, ecoregions, and aquatic ecology, and human factors such as reservoirs, land use and population change, water use, and water-quality issues. Characterization of the environmental setting is useful for understanding the physical, chemical, and biological characteristics of surface and ground water in the Mobile River Basin and the possible implications of that environmental setting for water quality. The Mobile River Basin encompasses parts of five physiographic provinces. Fifty-six percent of the basin lies within the East Gulf section of the Coastal Plain Physiographic Province. The remaining northeastern part of the basin lies, from west to east, within the Cumberland Plateau section of the Appalachian Plateaus Physiographic Province, the Valley and Ridge Physiographic Province, the Piedmont Physiographic Province, and the Blue Ridge Physiographic Province. Based on the 1991 land-use data, about 70 percent of the basin is forested, while agriculture, including livestock (poultry, cattle, and swine), row crops (cotton, corn, soybeans, sorghum, and wheat), and pasture land accounts for about 26 percent of the study unit. Agricultural land use is concentrated along the Black Prairie Belt district of the Coastal Plain. Urban areas account for only 3 percent of the total land use; however, the areal extent of the metropolitan statistical areas (MSA) may indicate more urban influences. The MSAs include urban areas outside of the city boundaries and can include adjacent counties. Seven MSAs are delineated in the Mobile River Basin, including Montgomery, Mobile, Tuscaloosa, Birmingham, Gadsden, Anniston, and Atlanta. The total population for the Mobile River Basin was about 3,673,100 in 1990. State water-quality agencies have identified numerous causes and sources of water-body impairment in the Mobile River Basin. In 1996, organic enrichment, dissolved oxygen depletion, elevated nutrient concentrations, and siltation were the most frequently cited causes of impairment, affecting the greatest number of river miles. Bacteria, acidic pH, and elevated metal concentrations also were identified as causes of impairment. The sources for impairment varied among river basins, were largely a function of land use, and were attributed primarily to municipal and industrial sources, mining, and agricultural activities.

Water-Resources Investigations Report

Ground-water resources of the Tallapoosa River basin in Georgia and Alabama - Subarea 5 of the Apalachicola-Chattahoochee-Flint and Alabama-Coosa-Tallapoosa river basins

Drought conditions in the 1980's focused attention on the multiple uses of the surface- and ground-water resources in the Apalachicola-Chattahoochee-Flint (ACT) and Alabama-Coosa-Tallapoosa (ACT) River basins in Georgia, Alabama, and Florida. State and Federal agencies also have proposed projects that would require additional water resources and revise operating practices within the river basins. The existing and proposed water projects create conflicting demands for water by the States and emphasize the problem of water-resource allocation. This study was initiated to describe ground-water availability in the Tallapoosa River basin of Georgia and Alabama, Subarea 5 of the ACF and ACT River basins, and to estimate the possible effects of increased ground-water use within the basin. Subarea 5 encompasses about 4,675 square miles (mi2) in Georgia and Alabama and contains parts of the Piedmont and Coastal Plain physiographic provinces. The Piedmont Province is underlain by a two-component aquifer system that is composed of a fractured, crystalline-rock aquifer and the overlying porous-media regolith aquifer. The Coastal Plain is underlain by a porous-media aquifer formed from the poorly consolidated deposits of sand, gravel, and clay. The conceptual model described for this study qualitatively subdivides the ground-water flow system into local (shallow), intermediate, and regional (deep) flow regimes. Ground-water discharge to tributaries mainly is from local and intermediate flow regimes and varies seasonally. The regional flow regime probably approximates steady-state conditions and discharges chiefly to major drains such as the Tallapoosa River, and in upstream areas, also to the Little Tallapoosa River and the Tallapoosa River. Ground-water discharge to major drains originates from all flow regimes. Mean-annual ground-water discharge to steams (baseflow) is considered to approximate the long-term, average recharge to ground water. The mean-annual baseflow was estimated using an automated hydrograph- separation method, and represents discharge from the local, intermediate, and regional flow regimes of the ground- water flow system. Mean-annual baseflow in Georgia was estimated to be 534 cubic feet per second (from the headwaters to the Georgia-Alabama State line), 3,250 ft3/s in Alabama, and 3,780 ft3/s for all of Subarea 5 (at the Subarea 5-Subarea 8 boundary). Stream discharge for selected sites on the Tallapoosa River and its tributaries were compiled for the years 1941, 1954, and 1986, during which sustained droughts occurred throughout most of the ACF-ACT area. Stream discharges were assumed to be sustained entirely by baseflow during the latter periods of these droughts. Estimated stream discharges near the end of the 1941, 1954, and 1986 drought years were 48, 15, and 85 ft3/s, respectively, at the Georgia-Alabama State line; and 481 , 126, and 448 ft3/s, respectively, at the mouth of the Tallapoosa River. Estimated baseflow near the end of the individual drought years was about 9 percent of the estimated mean-annual baseflow in Subarea 5. The potential exists for the development of ground-water resources on a regional scale throughout Subarea 5. Estimated ground-water use in 1990 was less than 1 percent of the estimated mean-annual baseflow, and about 6 percent of baseflow during the droughts of 1941, 1954, and 1986. Because ground-water use in Subarea 5 represents a relatively minor percentage of ground-water recharge, even a large increase in ground-water use in Subarea 5 in one State is likely to have little effect on ground-water and surface-water occurrence in the other. Indications of long-term ground-water levels declines were not observed; however, the number and distribution of observation wells for which long-term water-level measurements are available in Subarea 5 are insufficient to draw conclusions.

Alabama, Georgia

Ground-water resources of the Alabama River Basin in Alabama; Subarea 8 of the Apalachicola-Chattahoochee-Flint and Alabama-Coosa-Tallapoosa River Basins

Drought conditions in the 1980's focused attention on the multiple uses of the surface- and ground-water resources in the Apalachicola-Chattahoochee-Flint (ACF) and Alabama-Coosa-Tallapoosa (ACT) River basins in Georgia, Alabama, and Florida. State and Federal agencies also have proposed projects that would require additional water resources and revise operating practices within the river basins. The existing and proposed water projects create conflicting demands for water by the States and emphasize the problem of water-resource allocation. This study was initiated to describe ground-water availability in the Alabama River basin of Alabama, Subarea 8 of the ACF and ACT River basins, and to estimate the possible effects of increased ground-water use within the basin. Subarea 8 encompasses about 6,750 square miles in the Coastal Plain physiographic province in central and southwestern Alabama. The Alabama River extends from the juncture of the Coosa and Tallapoosa Rivers near the city of Montgomery, to its juncture with the Tombigbee River, near the town of Calvert in Washington County. Subarea 8 includes the Cahaba River basin from the physiographic 'Fall Line' at the city of Centreville in Bibb County, to its mouth in Dallas County; and the Alabama River basin from near Montgomery to the Alabama River cutoff, about 6 miles northeast of its juncture with the Tombigbee River. The study area is underlain by sedimentary deposits of Cretaceous, Tertiary, and Quaternary ages. Major aquifers underlying Subarea 8 are, from shallowest to deepest, the Coastal lowlands aquifer system, the Floridan aquifer system, the Lisbon aquifer, The Nanafalia-Clayton aquifer, the Ripley aquifer, the Eutaw aquifer, and the Tuscaloosa aquifer. The conceptual model described for this study qualitatively subdivides the ground-water flow system into local (shallow), intermediate, and regional (deep) flow regimes. Ground-water discharge to tributaries mainly is from local and intermediate flow regimes and varies seasonally. The regional flow regime probably approximates steady- state conditions and discharges chiefly to major drains such as the Alabama River, and in upstream areas, to the Cahaba River. Ground-water discharge to major drains originates from all flow regimes. Mean-annual ground-water discharge to streams (baseflow) is considered to approximate the long-term, average recharge to ground water. The mean-annual baseflow was estimated using an automated hydrograph- separation method, and represents discharge from the local, intermediate, and regional flow regimes of the ground-water flow system. Mean-annual baseflow discharging from Subarea 8 was estimated to be 20,300 cubic feet per second. Mean-annual baseflow represented about 61 percent of total mean-annual stream discharge for the period of record. Estimated and measured stream discharge for selected sites on the Alabama River and its tributaries were compiled for the years 1941, 1954, and 1986, during which sustained droughts occurred throughout most of the ACF-ACT area. Stream discharges were assumed to be sustained entirely by baseflow during the latter periods of these droughts. Estimated baseflow near the end of the individual drought years was about 17 percent of the estimated mean-annual baseflow at the Alabama River cutoff, the most downstream point of Subarea 8. The potential exists for the development of ground-water resources on a regional scale throughout Subarea 8. Estimated ground-water use in 1990 was less than 1 percent of the estimated mean-annual baseflow, and about 2.4 percent of baseflow during the droughts of 1941, 1954, and 1986. Because ground-water use in Subareas 5 and 6 represents a relatively minor percentage of ground-water recharge, even a large increase in ground-water use in Subareas 5 and 6 in Georgia probably would have little effect on the quantity of ground water and surface water in Alabama. In addition, ground-water use in Subarea 3 in Georgia probably h

Open-File Report

Magnitude and frequency of floods in Alabama

Methods of estimating flood magnitudes for recurrence intervals of 2, 5, 10, 25, 50,100, 200, and 500 years are described for rural streams in Alabama that are not affected by regulation or urbanization. Flood-frequency characteristics are presented for 198 gaging stations in Alabama having 10 or more years of record through September 1991, that are used in the regional analysis. Regression relations were developed using generalized least-squares regression techniques to estimate flood magnitude and frequency on ungaged streams as a function of the drainage area of a basin. Sites on gaged streams should be weighted with gaging station data that are presented in the report Graphical relations of peak discharges to drainage areas are also presented for siter along the Alabama, Black Warrior, Cahaba, Choctawhatchee, Conecuh, and Tombigbee Rivers. Equations for estimating flood magnitudes on ungaged urban streams (taken from a previous report) that use drainage area and percentage of impervious cover as independent variables also are given.

Alabama

Scour at selected bridge sites in Alabama, 1991-94

Scour data were collected at 15 sites on streams in Alabama during high flow conditions. The recurrence intervals of the streamflows ranged from less than 2 to 10 years. Scour depths measured near bridge piers ranged from 0.3 to 5.8 feet. The Colorado State University (CSU) local scour equation recommended in the Federal Highway Administration Hydraulic Engineering Circular No. 18 was used to estimate scour depths at the study sites. Estimated scour depths based on the CSU equation ranged from 2.5 to 12.7 feet with residuals (measured scour depth minus estimated scour depth) ranging from -8.1 to -1.4 feet. A comparison of the residuals with the estimated scour depths indicated that the CSU equation overestimated the measured scour depths throughout the range of measured data by an average of 434 percent.

Water-Resources Investigations Report