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Research about Apalachicola-Chattahoochee-Flint River basin

Source-linked reports with geographic coverage including Apalachicola-Chattahoochee-Flint River basin.

7 recordsLinked to original sources
USGS1996

Influences of environmental settings on aquatic ecosystems in the Apalachicola-Chattahoochee-Flint River basin

The watershed boundary of the Apalachicola-Chattahoochee-Flint (ACF) River basin defines an aquatic ecosystem whose water quality is the result of complex interactions of natural and human influences on land and water resources. Topics relating to the basin's environmental setting-its physical, biological, and cultural characteristics-are summarized to provide an understanding of factors that influence water quality and the health of aquatic ecosystems. The ACF River basin lies partly in southwestern Georgia, southeastern Alabama, and northwestern Florida and covers 19,800 square miles in the Blue Ridge, the Piedmont, and the Coastal Plain Provinces. The basin includes the drainages of the Chattahoochee River and the Flint River, which meet to form the Apalachicola River. The Apalachicola River flows into the Gulf of Mexico at Apalachicola Bay. Basin hydrology and water quality are influenced by 16 mainstem reservoirs, 13 of which are on the Chattahoochee River. Ground water in the basin is contained in six aquifers-the surficial aquifer system, the Floridan aquifer system, the Claiborne aquifer, the Clayton aquifer, the Providence aquifer, and the crystalline-rock aquifer. Physiography, climate, and hydrology of the ACF River basin provide natural conditions that support a rich and abundant diversity of plants and animals. Although most of the ACF River basin has been altered by human activities, the basin's environment is noteworthy for its remaining biological diversity and the role it plays in sustaining biological productivity in Apalachicola Bay. The Bay produces 90 percent of Florida's and 13 percent of the Nation's oyster harvest; and functions as a nursery for penaeid shrimp, blue crabs, and a variety of fin fish. The diversity of the basin's aquatic fauna is noteworthy because the basin is home to (1) the largest number of fish species among Gulf Coast drainages east of the Mississippi River, (2) the largest assemblage of freshwater fish in Florida, (3) the largest number of mollusc species among western Florida drainages, and (4) the highest species density of amphibians and reptiles on the continent north of Mexico. Population of the ACF River basin in 1990 was estimated at 2.6 million. Nearly 90 percent of the total population lived in Georgia, and nearly 60 percent lived in the Metropolitan Atlanta area. The 1990 basin population is projected to increase by 15 percent to 3.0 million by the year 2000, and by 30 percent to 3.4 million by 2010. The largest increases in populations are projected for the Metropolitan Atlanta area. In 1972-76, approximately 59 percent of the basin was covered by forest, 29 percent was agricultural, 5 percent was wetland, 4 percent was urban, and 3 percent was water or barren land. Most of the original land cover of the basin has been transformed by human activity. Timber is the basin's largest cash crop and most forests consist of second-growth stands or large acreages of planted pine. The dominant agricultural land use in the Piedmont Province is pasture and confined feeding for dairy, livestock, and poultry production. Row-crop agriculture, orchards, and silviculture are most common in the Coastal Plain Province. The top five crops in order from most to least acres harvested in 1990 were peanuts, corn, soybeans, wheat, and cotton. The water in the basin is used for public and industrial supply, irrigation, power generation, navigation, and recreation. Although most public-supply withdrawals in the Blue Ridge and Piedmont Provinces are from surface-water sources, with the exception of counties near or immediately below the Fall Line, all publicly supplied water in the Coastal Plain is withdrawn from ground-water sources. Ground water supplied 18 percent of the basin's population served by public supply. Total water withdrawn in the ACF River basin in 1990 was 2,098 million gallons per day (Mgal/d), of which Georgia withdrew 82 percent and Florida and Alabama each withdrew 9 percent. Power generation is the single largest water use. Sixteen of the basin's 22 power generating plants are located along the mainstem of the Chattahoochee River. The U.S. Army Corps of Engineers maintains a navigation channel from the mouth of the Apalachicola River to Columbus, Ga., on the Chattahoochee River and to Bainbridge, Ga., on the Flint River. Water quality in the basin is influenced by the operation of 137 municipal wastewater-treatment facilities. In 1990, 354 Mgal/d of municipal wastewater was discharged within the ACF River basin. Eighty-eight percent of the wastewater was discharged into the Chattahoochee River basin, 10.6 percent into the Flint River basin, and 1.4 percent into the Apalachicola River basin. Two-thirds of the 938 stream miles in the Georgia portion of the ACF River basin having water quality that does not meet or only partially meets the designated-use criteria in the Chattahoochee River basin. The Chattahoochee River is the most heavily-used water resource both in the ACF River basin and in Georgia. Urban runoff or unknown nonpoint sources are cited as the causes of water-quality regulations in 72 percent of violations. The remaining causes primarily are combined sewer overflows in the Atlanta area, and discharges from municipal or industrial treatment facilities with inadequate treatment capabilities or operational deficiencies.

Alabama, Florida, Georgia↗
USGS1996

Nutrient sources and analysis of nutrient water-quality data, Apalachicola-Chattahoochee-Flint River basin, Georgia, Alabama, and Florida, 1972-90

In 1991, the U.S. Geological Survey began full-scale implementation of the National Water-Quality Assessment (NAWQA) program. One of the initial tasks of the NAWQA program is to compile and evaluate existing data from individual study units. Available nutrient data from 1972 through 1990 water years were used to estimate nutrient sources to the Apalachicola–Chattahoochee–Flint (ACF) River basin and describe the presence, distribution, and transport of nutrients in surface and ground waters. In 1990, about 2,500 tons of nitrogen and 1,100 tons of phosphorus were discharged as point-source loads by 127 municipal wastewater-treatment facilities (WWTF). Nonpoint-source inputs, an unknown percentage of which entered the hydrologic system, included about 120,000 tons of nitrogen and 28,000 tons of phosphorus from animal manure; 82,000 tons of nitrogen and 20,000 tons of phosphorus applied as fertilizer; and 24,000 tons of nitrogen from atmospheric deposition. Estimates of nutrient input to the ACF River basin were not made for natural sources and for the following anthropogenic sources: industrial-wastewater effluent; storm drains; sanitary and combined sewer outflows; and runoff from agricultural, urban, and suburban areas. Nutrient outflow from the Apalachicola River into Apalachicola Bay, Fla., was about 13 percent of estimated nitrogen sources and about 3 percent of estimated total-phosphorus sources in the ACF River basin. For 1972–90, nutrient concentrations in surface water were high enough to warrant concerns about accelerated eutrophication based on total-phosphorus concentrations and to warrant concerns intermittently about toxicity to fish based on dissolved-ammonia concentrations downstream of wastewater-treatment outfalls from Metropolitan Atlanta and LaGrange, Ga. Many improvements to the water quality of the Chattahoochee and Flint Rivers in the 1980’s and early 1990’s can be directly attributed to improvements in WWTF, legislation directed at decreasing point-source loads of phosphorus, and changes in locations of wastewater-treatment outfalls. However, limited data indicate that nonpoint-source inputs increased upstream of Atlanta and in the Chipola River watershed. Significant increases in nutrient concentrations, loads, and yields occurred from upstream to downstream of the metropolitan areas of Atlanta, Ga.; Columbus, Ga., and Phenix City, Ala.; and Albany, Ga. The highest mean-annual yields estimated in the ACF River basin for total nitrogen (2.9 tons per square mile (tons/mi 2 )), total-inorganic nitrogen (2.0 tons/mi 2 ), dissolved ammonia (1.1 tons/mi 2 ), and total phosphorus (0.75 tons/mi 2 ) were downstream of Atlanta. Most significant trends in nutrient-concentration data from 1980–90 in the Chattahoochee River and the Middle and Lower Flint River basins were increasing, except dissolved ammonia which decreased at several sampling sites in reaches downstream of Atlanta, Columbus and Phenix City, and Albany. At sampling sites on the Chattahoochee and Flint Rivers downstream of Atlanta and Albany, decreasing trends in dissolved-ammonia concentration and increasing trends in dissolved-nitrate concentration were the result of improved wastewater treatment at WWTF. Dissolved-ammonia concentrations decreased and dissolved-nitrate concentrations increased along river reaches downstream of wastewater-treatment facility outfalls for Atlanta and Albany because of nitrification of ammonia to nitrate. Increasing trends in total-phosphorus concentrations are an accurate representation of data for the period 1980–90. However, legislated restrictions on the use of phosphate detergents and improvements to WWTF in the late 1980’s and early 1990’s, resulted in substantial reductions of phosphorus concentrations in wastewater effluent and in rivers at many locations in the 1990’s. Reservoirs affect nutrient transport because of uptake by phytoplankton and aquatic plants, denitrification,and accumulation of phosphorus associated with sediment in reservoirs. Yields of total-inorganic nitrogen, dissolved ammonia, dissolved nitrate, and total phosphorus decreased between sampling sites upstream and downstream of four reservoirs on the Chattahoochee River. The only exception was the yield of dissolved ammonia increased slightly from upstream to downstream of Lake Sidney Lanier. Much of the nutrient load in the Chattahoochee River downstream of Atlanta is utilized by algae or settles out primarily in West Point Lake, and to a lesser extent, in Lake Harding and Walter F. George Reservoir. In general, the Flint River arm of Lake Seminole had significantly higher concentrations of nutrients than the Chattahoochee River arm of Lake Seminole, which may be the result of the large percentage of the Middle and Lower Chattahoochee River in backwater from reservoirs, the absence of reservoirs on the Flint River downstream of Albany until Lake Seminole, and nonpoint-source inputs of nutrients from intensively farmed areas in the Lower Flint River basin. Decreases in dissolved-ammonia, dissolved-nitrate, and total-phosphorus concentrations in reservoirs and backwater along the Chattahoochee River from West Point Lake to Lake Seminole during summer months are related to the seasonality of phytoplankton production. The Chipola River had the highest yields of dissolved nitrate (1.2 tons/mi 2 ) estimated in the ACF River basin. Estimated loads of dissolved nitrate increased fairly steadily from 500 to 1,500 tons per year from 1972–90. These factors strongly suggest an agricultural nonpoint source of elevated dissolved-nitrate concentrations from increased irrigated agriculture and fertilizer applications in the Chipola River watershed. Analyses of nutrients in ground water within the ACF River basin for 1972–90 water years were restricted because of limited available data. The distribution of nitrate concentrations in the ACF River basin for 1972–90 water years included 10 percent of wells and 6 percent of springs with concentrations that probably have elevated nitrate concentrations (3.1 to 10 milligrams per liter (mg/L)), and 1 percent of wells with median nitrate concentrations exceeding the maximum contaminant level of 10 mg/L. Dissolved-nitrate concentrations were significantly lower in the Providence aquifer than in the Floridan aquifer system and the crystalline-rock aquifers. Dissolved-nitrate concentrations in wells used for public supply were significantly lower than in wells used for domestic use or unused wells.

Alabama, Florida, Georgia↗
USGS1995

Use and occurrence of pesticides in the Apalachicola-Chattahoochee-Flint River basin, Georgia, Alabama, and Florida, 1960-91

The Apalachicola-Chattahoochee-Flint (ACF) River basin was one of the first 20 study units selected in 1991 by the U.S. Geological Survey for its National Water-Quality Assessment (NAWQA) program. Because pesticide contamination of surface water and ground water is a concern nationwide, a major emphasis of the NAWQA program is to examine the occurrence and distribution of pesticides in the water resources of these study unit basins. An understanding of the types and distribution of land uses; pesticide properties, pest-control practices, and pesticide use; and an evaluation of the occurrence and distribution of pesticides in the water resources of the ACF are necessary to meet this objective of the NAWQA program. This report describes land use and pesticide use at a county level, and the occurrence and distribution of pesticides in the water resources of the ACF River basin on the basis of previously-collected data. About 33 percent of the ACF River basin is used for agriculture, 16 percent is used for silviculture, and about 5 percent of the basin is in urban and suburban settings; primarily the Columbus, Albany, and Atlanta Metropolitan areas. The remainder is in wetlands and non-silvicultural forest. A broad range of synthetic-organic herbicides, insecticides, and fungicides are applied to land in agricultural, silvicultural, urban, and suburban areas. The period of intensive pesticide applications extends from March to October. Pesticide data available for the period from 1971 through 1989 in the U.S. Geological Survey National Water Information System (NWIS) and for the period from 1960 through 1991 in the U.S. Environmental Protection Agency Storage and Retrieval System (STORET) were analyzed to describe the occurrence and distribution of pesticides in water resources of the ACF River basin. Collectively, the NWIS and STORET databases contain about 19,600 individual analyses for pesticide concentration in the ACF River basin. Pesticide concentrations were at or above a minimum reporting level in about five percent of all analyses. Most of the pesticide analyses and most of the analyses having concentrations above minimum reporting levels in these databases are for organochlorine insecticides in samples collected five or more years before this study. With few exceptions, most of organochlorine insecticides are now banned from use in the United States. Concentrations of currently (1991) used pesticides were at or above a minimum reporting level in about 0.3 percent of the analyses. The geographic patterns in the occurrence and distribution of pesticides in the ACF River basin (as defined by data collected during 1960-91) are, as expected, somewhat defined by land-use patterns. DDT (together with DDD and DDE) were detected in wide distribution in the sediments and aquatic biota of primarily mainstem and reservoir sites in the Chattahoochee, Flint, and Apalachicola drainages. DDT was used through 1973 as an insecticide on cotton, fruits, and vegetables; and for mosquito control, so its widespread occurrence in both urban and agricultural settings is consistent with its use. Chlordane, heptachlor, dieldrin, and related compounds were agriculturally used through 1974, but predominantly as termiticides through the late 1980’s. Compounds in these groups have been found in the sediments and aquatic biota of tributary streams draining the Atlanta Metropolitan area and of mainstem reaches and reservoirs of the Chattahoochee River downstream from the Atlanta and Columbus, Ga., Metropolitan areas. The phenoxy-acid herbicides are widely used in residential, commercial/industrial, agricultural, and silvicultural areas of the ACF River basin. Detectable concentrations of 2,4-D were found in most of the surface-waters sampled in the Atlanta Metropolitan area. It is unfortunate that only limited inference can be drawn on temporal patterns. Many of the Federal and State agency pesticide-monitoring programs have been targeted to known sources and areas of contamination, an approach consistent with regulatory requirements focused on human health; and either were synoptic in nature or were conducted during a limited period of time. Thus, the composite temporal picture represented by these sampling efforts is inherently patchy.

Alabama, Florida, Georgia↗
USGS1993

Estimated use of water in the Apalachicola-Chattahoochee-Flint River basin during 1990, with state summaries from 1970 to 1990

The Apalachicola-Chattahoochee-Flint River basin covers approximately 19,800 square miles in parts of Alabama, Florida, and Georgia. Most of the basin lies within Georgia as does most of the population. Most of the water withdrawn in the basin in 1990 was withdrawn in Georgia (82 percent). Withdrawals in Florida and Alabama each accounted for 9 percent of the total withdrawal in the basin. Water with- drawn in the basin for 1990 totaled 2,098 million gallons per day, of which approximately 17 percent (351 million gallons per day) was consumed. Of the total water used, nearly 86 percent was withdrawn from surface-water sources, and the remaining 14 percent was withdrawn from ground-water sources. Nearly 63 percent of the surface water used in the basin during 1990 was for thermoelectric power generation; other surface water uses included public supply (24 percent), self-supplied commercial- industrial use (12 percent), and agricultural use (4 percent). Nearly 58 percent of the ground water used in the basin for 1990 was used for agricultural irrigation; other ground-water uses included public supply (21 percent), self-supplied domestic use (11 percent), self-supplied commercial-industrial use (9 percent), and thermoelectric power generation (less than 1 percent). The Chattahoochee River supplied most of the surface water used in the basin (64 percent) and the Floridan aquifer system supplied most of the ground water used (44 percent) in 1990. During 1990, 39,815 Mgal/d of water was used to produce 35,843 gigawatthours of electricity. Of that total, 1.076 Mgal/d was used to produced 33,460 gigawwatthours of electricity at 8 fossil fuel facilities and 38,740 Mgal/d was used to produce 2,384 gigawatthours of electricity at 14 hydroelectric facilities.

Alabama, Florida, Georgia↗