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Research about Georgia

Source-linked reports with geographic coverage including Georgia.

At least 577 records · Page 32Linked to original sources
USGS1977

Techniques for Estimating Flood-Depth Frequency Relations on Natural Streams in Georgia

Regional relations are defined for estimating the depth of floods having recurrence intervals of 10, 50, and 100 years on streams with natural flow in Georgia. Multiple-regression analysis of station data is used to define the relations between flood depths and frequency for streams draining from 1 to 1,000 square miles, and for 10 climatological and physical basin characteristics. The analysis indicates that the drainage area of the basin is the most significant variable. Five regions having distinct flood-depth frequency characteristics are delineated. The developed relations, expressed as equations and graphs, are considered usable for any site in Georgia where the drainage area is between 1 and 1,000 square miles, and the flow is natural; exceptions include streams that are urbanized, regulated, tide affected, channelized, or where manmade structures significantly affect peak stages.

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USGS1977

Urban and regional land use change detected by using Landsat data

The Atlanta Regional Commission and the Earth Resources Observation Systems Data Center participated in a demonstration of the use of Landsat digital data to detect land use change in the Atlanta, Ga., area. Temporal overlays combining Landsat band-5 data from October 1972 and 1974 were made by using the General Electric Image 100 system. The 1972 data were divided by the 1974 data, and low ratios indicate areas where land use and land cover had changed. These low ratios were classified into a land-use-change theme. A classification based on the use of the four bands of the multispectral scanner data, taken in 1974, yielded six land use categories: (1) Commercial-industrial-multifamily, (2) single-family residential, (3) cleared land, (4) open space, (5) forested land, and (6) water. These six 1974 categories and the change theme were combined to determine changes between 1972 and 1974.

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USGS1976

Floodflow characteristics, North Fork Peachtree Creek at Interstate 85, DeKalb County, Georgia

This report has been prepared as part of a program of water-resources investigations, under the provisions of a cooperative agreement between the Highway Division, Department of Transportation, State of Georgia, and the U.S. Geological Survey. The Highway Division plans modification of the bridge crossing of North Fork Peachtree Creek at Interstate 85 and the addition of frontage roads and bridges upstream and downstream of Interstate 85, DeKalb County, Ga. The purpose of the study was to determine the flood characteristics for North Fork Peachtree Creek in the vicinity of Interstate 85 in relation to (1) major changes that have occurred since 1956 and (2) the effects of the proposed highway modifications and additions in the vicinity of the Interstate 85 crossing. Analyses of flow characteristics for the 50- and 100year floods were made for the following conditions: Natural conditions before construction of Interstate 85 (1952). Conditions after construction of Interstate 85 but prior to construction of Century Center, an office complex downstream from Interstate 85 (1968). Present conditions (1975) after construction of Interstate 85 and Century Center. Conditions for proposed bridge modification and highway additions, assuming that both frontage road bridges will be constructed higher than the 100-year flood. In addition, the study included backwater computations, area of opening under high water, and average velocity at the proposed Interstate 85 bridge opening for both the 50- and 100-year floods. All elevations referred to in this report are to highway datum, which is mean sea level.

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USGS1976

Occurrence and distribution of color and hydrogen sulfide in water of the principal artesian aquifers in the Valdosta area, Georgia

Hydrogen sulfide and color occur in objectionable amounts in ground water from the principal artesian aquifer in the Valdosta area. Any future ground-water development should be planned with this in mind. Areas where water high in hydrogen sulfide or color is likely to be tapped by wells occur north (color) and south (sulfide) of the city. A hydrogen sulfide concentration of 1.0 mg/1 (milligram per litre) and a color intensity of 15 platinum-cobalt units were chosen as limits. Water with high sulfate is likely to be a problem in wells deeper than about 540 ft (165 m). At that depth, high-sulfate water was found in the northern part of Valdosta. Heavy pumpage concentrated in a small area may cause high-sulfate water to migrate vertically upward into shallower wells.

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USGS1976

Flood-frequency analysis for small natural streams in Georgia

Flood information from 104 project basins (0.1 to 20 square miles) and data available from 170 larger basins (20 to 1,500 square miles) are analyzed to provide planners and designers with relations for estimating the magnitude and frequency of flood-peak discharges on small natural streams in Georgia. In 1963 the U.S. Geological Survey, in cooperation with the Georgia Department of Transportation and the Federal Highway Administration,U.S. Department of Transportation, began this program to collect and analyze flood-peak data from small drainage basins. More than 90 percent of the project activity was directed toward the acquisition and processing of data for more than two thousand rainfall-runoff periods occurring during 1964-74 at the 104 project stations. Storm rainfall data were computed at 5-minute intervals from records of six long-term (about 75 years) National Weather Service stations. The U.S. Geological Survey mathematical rainfall-runoff model is used to synthesize long-term flood records for about 80 percent of the project stations. Station flood-frequency data are developed, using the log-Pearson Type III distribution with regionalized skew coefficients. Multiple regression analysis is used to define relations between flood-frequency station data for small and large streams and 10 physical and climatological basin characteristics. The analysis indicates the drainage-basin size is the most significant variable. Five regions having distinct flood-peak characteristics are delineated. One of these regions, known as the Sand Hills, has not been delineated previously as an area of "low" flood runoff. The developed relations, expressed as equations and nomographs, are considered usable for virtually any site in Georgia where ne drainage area is between 0.1 and 20 square miles, and the flow is natural.

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USGS1976

Water resources data for Georgia, water year 1975

Water resources data for the 1975 water year for Georgia consists of records of stage, discharge, · and water quality of streams; stage and contents of lakes and reservoirs. This report contains discharge records for 91 gaging stations; stage only records for one gaging station; stage and contents for 16 lakes and reservoirs; water quality for 16 continuous stations and 78 periodic stations. Also included are 99 crest-stage partial-record stations and two low-flow partial-record stations. Additional water data were collected at various sites, not part of the systematic data collection program, and are published as miscellaneous measurements. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Georgia.

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USGS1975

Cedar Creek at Cedartown, Georgia-- floodflow characteristics at bridge site of Georgia Avenue relocation (supplement to open-file report 75-46)

The May 1974 U.S. Geological Survey open-file report 75-46, "Cedar Creek at Cedartown, Georgia, Floodflow Characteristics at Georgia Avenue, Relocation and Canal Street Extension," prepared at the request of the Georgia Department of Transportation, described the hydraulic characteristics of the Georgia Avenue relocation as constructed in April 1974, and evaluated the effects of three proposed changes in roadway grades at this crossing.

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USGS1975

Palynological evidence for late Cretaceous, Paleocene, and early and middle Eocene ages for strata in the kaolin belt, central Georgia

Falynomorphs of Late Cretaceous (Maestrichtian), Paleocene, Paleocene or early Eocene (Wilcox), and middle Eocene (Claiborne) ages have been found in lignitic and carbonaceous clays and silts in the Tuscaloosa Formation, as used in central and east-central Georgia. The occurrence of palynomorphs of Maestrichtian (Navarro) age above thick kaolin deposits at one locality and a suite of Claiborne age fossils below a thick deposit at another locality establish that kaolins of both Late Cretaceous and middle Eocene or younger ages are present. However, the recognition of the Paleocene and middle Eocene beds in the Tuscaloosa Formation of several authors indicates that part of it is much younger than previously thought. The palynomorphs and other characteristics of the carbonaceous materials of Cretaceous and middle Eocene ages indicate freshwater accumulation. The beds of Paleocene age contain both terrestrial and marine forms indicating deposition in marine swamps or estuaries. These findings and the range in ages support the conclusion that the deptositional history of the Late Cretaceous and early Tertiary formations in Georgia is complex.

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USGS1974

Water resources data for Georgia, water year 1973

Water resources data for the 1973 water year for Georgia include records of streamflow or reservoir storage at gaging stations, partial record stations, miscellaneous sites, and records of water-quality data on the chemical and physical characteristics of surface-water as well as records for a few pertinent gaging and water-quality stations in bordering States. The records were collected and computed by the Water Resources Division of the U.S. Geological Survey under the direction of John R. George, district chief. These data represent the Georgia portion of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies.

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USGS1974

Geologic and hydrologic control of chloride contamination in aquifers at Brunswick, Glynn County, Georgia

Water from a brackish-water zone (1,050-1,350 ft) has concentrations as high as 2,150 milligrams per liter chloride, and concentrations are suspected to be higher than 3,000 milligrams per liter chloride. This brackish water has been identified as the source of the water that contaminates the upper and lower fresh-water-bearing zones of the principal artesian aquifer. The confining unit separating the fresh and brackish water seems to contain breaks that act as vertical conduits for the movement of brackish water into the fresh-water zones of the aquifer. Faults are suspected to be responsible for the breaks in the confining unit. The rate of upward movement of brackish water seems to be a function of the rate of water-level decline in the aquifer. There are two main areas of brackish-water intrusion. One area is near Bay and Prince Streets, and the other area is near Reynolds and Q Streets. Successive maps showing chloride ion concentration trace the movement of the chloride front northward in the Bay Street area at the rate of about 350 feet per year toward the center of pumping. An average of about 400 gallons per minute of water containing 2,000 milligrams per liter chloride invaded the upper water-bearing zone between December 1962 and December 1966. A like amount may have entered the lower water-bearing zone. Maximum chloride concentration in the upper water-bearing zone is 1,540 milligrams per liter in the Bay Street area and 640 milligrams per liter in the Reynolds Street area. In a few areas, where individual wells have been drilled deep enough to penetrate the confining unit over the brackish-water zone, the well furnishes a conduit for brackish water to recharge the fresh-water aquifer. Plugging the lower part of these wells usually reduces the chloride concentration of the water. The chloride concentration of water in the principal artesian aquifer can probably be reduced by use of interceptor wells, relief wells, or well-field spacing. Interceptor wells would prevent laterally moving brackish water from contaminating a well field. A relief well would tap and withdraw poor quality water from only the brackish-water zone to lower the head in that zone and decrease the rate of leakage into the fresh-water aquifer. Wider spacing of wells would prevent the development of a deep cone of depression and the steeper hydraulic gradients that accompany it. The brackish water pumped by the interceptor or relief wells could be used for industry, aquaculture, recreation, or for other processes in which the chloride content is not critical.

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USGS1973

Water resources data for Georgia, water year 1972

Water resources data for the 1972 water year for Georgia include records of streamflow or reservoir storage at gaging stations, partial-record stations, and records of water-quality data on the chemical and physical characteristics of surface-water as well as records for a few pertinent gaging and water-quality stations in bordering States. The records were collected and computed by the Water Resources Division of the U.S. Geological Survey under the direction of John R. George, district chief. These data represent the Georgia portion of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies. Through September 30, 1960, the records of discharge and stage of streams and contents and stage of lakes or reservoirs were published in an annual series of U.S. Geological Survey water-supply papers entitled, "Surface Water Supply of the United States." Beginning with the 1961 water year, streamflow records and related data have been released by the Geological Survey in annual reports by State. Distribution of these reports is limited; they are designed primarily for rapid release of data shortly after the end of the water year to meet local needs. The streamflow records for 1961-65 are published in the Geological Survey water-supply paper series entitled, "Surface Water Supply of the United States, 1961-65", and those for 1966-70 will be published in a similar series. The Geological Survey has published records of chemical quality, suspended sediment, and water temperatures since 1941 in an annual series of water-supply papers entitled, "Quality of Surface Waters of the United States." Beginning with the 1964 water year, water-quality records also have been released by State in conjunction with stream-flow records or in a separate volume.

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