U.S. Department of the Interior

U.S. Geological Survey

Fact Sheet 2013–3002

January 2013

In 2011, new 

record-low monthly 

discharge occurred 

at 52 of 113 streamgages that have 

20 or more years 

of data. These 

52 streamgages are 

located throughout Georgia. Most of the State received lower-than-normal precipitation; 

from central Georgia to Florida, the State received 50–75 percent of normal precipitation. 

Normal is defined as a 30-year average for 1971–2000.

New record-low 7-day average discharge occurred at 24 of 113 streamgages that have 20 or 

more years of data in 2011. The majority of these streamgages were located in southern Georgia.

These maps represent hydrologic conditions during 

the 2011 WY compared to available historical data. The 

colors represent runoff (flow per unit area) as a percentile 

of long-term averages. Runoff was calculated for each basin 

and assumed to be uniform over the entire basin area. Only 

streamflow stations with a complete daily-flow dataset for 

the 2011 WY were used (U.S. Geological Survey, 2012c). For 

the first quarter of the 2011 WY (October–December 2010), 

much of the State was observing “below normal” and 

“much below normal” runoff conditions as a result of 

extreme temperatures and lack of precipitation during the preceding summer months of 

the 2010 WY (A). Little to no precipitation kept the majority of the State in drought during 

the second and third quarter of the 2011 WY (B, C). After receiving 50–75 percent of normal 

precipitation from central Georgia to Florida during the 2011 WY, the majority of the State 

was in an extreme drought during the fourth quarter as runoff was “much below normal,” 

and large areas of the State observed some of the lowest runoff conditions on record (D). 

Much above normal, > 90

Highest

Much below normal < 10

Lowest

Above normal, 76 to 90

Normal, 25 to 75

Below normal, 10 to 24

EXPLANATION

Percentile classes

B. 01/01/11–

 03/30/11

D. 07/01/11–

 09/30/11

C. 04/01/11–

 06/30/11

A. 10/01/10–

 12/31/10

GEORGIA

New monthly minimum 2011 New 7 day minimum 2011

Percent of normal 

 precipitation during 2011

New monthly minimum

Streamgage

New 7-day average minimum

50–74 percent

75–89 percent

90 percent and greater

EXPLANATION

1

Water year is the period October 1 through 

September 30 and is designated by the year 

in which it ends. For example, the 2011 water 

year began on October 1, 2010, and ended on 

September 30, 2011.

Quarterly Hydrologic Conditions in Georgia for 2011 WY, Based on Drainage Basin Runoff 

Extreme Drought: Summary of Hydrologic Conditions 

in Georgia, 2011

The United States Geological Survey 

(USGS) Georgia Water Science Center 

(GaWSC) maintains a long-term hydrologic 

monitoring network of more than 320 realtime streamgages, including 10 real-time 

lake-level monitoring stations and 63 realtime water-quality monitors. Additionally, the 

GaWSC operates more than 180 groundwater 

wells, 35 of which are real-time. One of the 

many benefits from this monitoring network 

is that the data analyses provide an overview 

of the hydrologic conditions of rivers, creeks, 

reservoirs, and aquifers in Georgia. 

Streamflow data are verified throughout 

the year by USGS hydrographers, and this 

information is available to water-resource 

managers, recreationalists, and Federal, State, 

and local agencies. Hydrologic conditions are 

determined by comparing the results of statistical analyses of the data collected during the 

current water year1 (WY) to historical data 

collected over the period of record. Changing 

hydrologic conditions emphasize the need for 

accurate, timely data to help Federal, State 

and local officials make informed decisions 

regarding the management and conservation 

of Georgia’s water resources for agricultural, 

recreational, ecological, and water-supply needs 

and for use in protecting life and property. 

On August 31, 2011, the Office of the 

State Climatologist reported extreme drought 

conditions in almost all areas of Georgia 

south of the Georgia mountains and that all 

counties in Georgia were classified as being 

in moderate, severe, or extreme drought. 

Also reported were soil moistures at the 

fifth percentile, indicating that, statistically, 

soils would have more moisture 95 out of 

100 years based on historical data. Wildfire 

danger was rated from high to extreme by 

the Georgia Forestry Commission, and in 

August 2011 Georgia had twice as many 

acres of scorched land compared to the 

long-term August average (Stooksbury, 

2011). The GaWSC network reported several 

streamgages with 20 or more years of record 

experiencing record low flows, including 

02202500 Ogeechee River near Eden, Ga., 

02226000 Altamaha River at Doctortown, 

Ga., and 02353000 Flint River at Newton, 

Ga. Also, several streamgages recorded no 

flow for several days, including 02314500 

Suwanee River at U.S. 441 at Fargo, Ga., 

for only the fifth time in 79 years of record. 

Streamflow and Groundwater Data

Daily, monthly, and yearly streamflow 

and groundwater statistics from the 

2011 USGS annual data report (ADR; 

U.S. Geological Survey, 2012a) were 

used to develop this summary. Data for 

WYs 1999–2011 can be accessed online 

at http://ga.water.usgs.gov/publications/

pubswdr.html. At this Web site, a digital map 

allows the user to search for current and 

historical data and graphics collected as part 

of the USGS monitoring network. 

New Minimum Streamflows
2

C O A S T A L P L A I N

PIEDMONT

BLUE

RIDGE

VALLEY

AND

RIDGE

Satilla–Suwannee–

St Marys–Ochlockonee

Oconee– Ocmulgee–Altamaha

Savannah–Ogeechee

Chattahoochee–Flint

Coosa– Tallapoosa–

Tennessee

Base modified from U.S. Geological Survey

1:2,000,000-scale digital data

N

0 30 60 MILES

0 30 60 KILOMETERS

Streamgage 

 and number

EXPLANATION

Atlanta

GEORGIA

ALABAMA

SOUTH

CAROLINA

FLORIDA

02213000

Chattahoochee

Altamaha River

Ogeechee River

Atlantic Ocean

Savannah River

Flint River

Oconee River

River

River

Ocmulge e

Withlacoochee

Chattooga R

Sweetwater

Jackson

Lake

Weiss

Lake

River

Creek

02213000

02318500

02337000

02398000

2010 2011

2010 2011

02398000 Chattooga River at Summerville, Georgia

100

1,000

10,000

100

1,000

10,000

7-day average discharge,

in cubic feet per second

Daily discharge,

in cubic feet per second

10

100,000

O N D J F M A M J J A S

2010 2011

10

100,000

Historical daily flow

2011 daily mean

EXPLANATION

Minimum

Median

Maximum

2011 water year

Much above normal, ≥ 90

Much below normal ≤ 10

Above normal, 76 to 89

Normal, 25 to 75

Below normal, 11 to 24

Historical (percentile)

EXPLANATION

Ocmulgee River at Macon, Ga. 02213000

The Ocmulgee River flows out of Jackson Lake and 

joins the Oconee River to form the Altamaha River (U.S. 

Geological Survey, 1975). The 7-day average streamflows 

were mostly in the normal range from October through 

March. After an extended period of lower-than-normal 

precipitation, streamflows were “much below normal” 

for the remainder of the 2011 WY and came close to 

setting new record lows. Daily discharge remained near 

historical median flows for most of the 2011 water year.

Chattooga River at Summerville, Ga. 02398000

The Chattooga River flows in the northwestern 

corner of Georgia and into Alabama where it flows 

into Weiss Lake (U.S. Geological Survey, 1975). The 

northwestern corner of Georgia received 90–110 percent 

of normal precipitation in the 2011 WY. Daily discharge 

and 7-day average streamflow for the 2011 WY was 

predominately in the “normal” range.

Daily Discharge 

Hydrographs show the 7-day average for 2011 as compared to 

historical 7-day averages. Data are categorized in percentile ranges 

from “much above normal” (greater than the 90th percentile) to 

“much below normal” (less than the 10th percentile) (U.S. Geological 

Survey, 2012a).

7-Day Average Discharge 

Hydrographs show 2011 daily-mean streamflow, in cubic feet per 

second, as compared to historical minimum and median streamflow 

for the entire period of record (U.S. Geological Survey, 2012a).

Daily Discharge and 7-Day Average 

Streamflow Conditions, 2011 Water Year

7-day average discharge,

in cubic feet per second

Daily discharge,

in cubic feet per second

100

1,000

10,000

100,000

O N D J F M A M J J A S

2010 2011

02213000 Ocmulgee River at Macon, Georgia 

100

1,000

10,000

100,000
3

02337000 Sweetwater Creek near Austell, Georgia

100,000

100

10

1

1,000

10,000

100,000

100

10

1

1,000

10,000

O N D J F M A M J J A S

2010 2011

7-day average discharge, 

in cubic feet per second

Daily discharge,

in cubic feet per second

10

1

100

1,000

10,000

10

1

100

1,000

10,000

02318500 Withlacoochee River at US 84, near Quitman, Georgia

O N D J F M A M J J A S

2010 2011

7-day average discharge,

in cubic feet per second

Daily discharge,

in cubic feet per second

100,000

100,000

0 

5 

10 

15 

20 

0

5

10

15

20

25

Well 03PP01, Walker County 

O N D J F M A M J J A S

2010 2011

Depth to water level

below land surface, in feet

Depth to water level

below land surface, in feet

Daily mean discharge,

in cubic feet per second

Precipitation,

in inches

0

1,000

2,000

3,000

4,000

5,000

6,000

7,000

03568933

03PP01

0

2

4

6

8

10

02384500

Elevation above National

Geodetic Vertical Datum

of 1929, in feet

730

725

720

705

710

715

Sweetwater Creek near Austell, Ga. 02337000

Sweetwater Creek is a major tributary of the 

Chattahoochee River (U.S. Geological Survey, 1975). The 

7-day average streamflow fluctuated between “normal” 

and “much below normal” from October through April 

gradually declining to “much below normal” during 

the latter part of the 2011 WY as the area received 

10 –20 percent below-normal precipitation. Several daily 

discharges reached new record lows during the months 

of August and September.

Withlacoochee River at US 84 near Quitman, Ga. 

02318500

The Withlacoochee River flows in the Ochlockonee 

River basin in the southern coastal plain of Georgia (U.S. 

Geological Survey, 1975). For most of the 2011 WY, 7-day 

average streamflow conditions were “below normal” to 

“much below normal” and came close to the record low 

recorded in 1940. Several daily discharges reached new 

record lows during the months of January, May, June, 

July, August, and September.

Well 03PP01 is 

in Walker County 

in northwestern 

Georgia and is 

completed in the 

valley and ridge 

aquifer in the 

Chickamauga 

limestone. Water 

storage is in the 

regolith, primary 

openings, and 

secondary 

fractures and 

solution openings 

in rock (Peck and 

others, 2011). 

Water levels are 

influenced mainly 

by precipitation 

and local pumping 

(Cressler, 1964). The 

water level in well 

03PP01 responds to 

seasonal change 

similarly to streamflow at the nearby streamgage on Lookout Creek 

near New England, Ga. (03568933), which indicates atmospheric, 

surface-water, and groundwater interactions. The water level in well 

03PP01 was near the historical daily median for much of the 2011 WY. 

Climate Response Network 

The USGS maintains a network of groundwater wells to 

monitor the effects of droughts and other climate variability on 

groundwater levels. These wells are part of the Climate Response 

Network, which is designed to measure the effects of climate on 

groundwater levels in unconfined aquifers or near-surface confined 

aquifers where pumping or other human influences on groundwater 

levels are minimal (U.S. Geological Survey, 2007, 2012b). The 

national network consists of about 130 wells, of which 15 are 

located in Georgia. These wells are monitored as part of the USGS 

Groundwater Resources and Cooperative Water Programs. Current 

conditions of groundwater wells in the Climate Response Network 

can be accessed online at http://groundwaterwatch.usgs.gov. The 

hydrographs presented are for selected wells in Georgia with at 

least 5 years of continuous data. 
4

Range of historical daily 

 minimum and maximum 

Daily mean Daily mean water level

Historical median

2011 groundwater level

EXPLANATION

Stream discharge

Groundwater level

EXPLANATION

2010 2011 2010 2011

GA

Surficial

Aquifers in Georgia

Upper

Floridan

SC

AL

FL

Crystalline- rock

0 

5 

10 

15 

20 

25 

–10

0

10

20

30

Well 07H003, Miller County 

O N D J F M A M J J A S

2010 2011

Depth to water level

below land surface, in feet

Depth to water level

below land surface, in feet

Daily mean discharge,

in cubic feet per second

Precipitation,

in inches

Elevation above National

Geodetic Vertical Datum

of 1929, in feet

157

167

197

187

177

0

100

200

300

400

500

02353500 07H003

0

5

10

02333500

Streamgage and number

Monitoring well and identifier

EXPLANATION

02333500

16MM02

6.5 

7 

7.5 

8 

8.5 

9 

7

6

8

9

10

Well 37P116, Chatham County 

O N D J F M A M J J A S

2010 2011

Depth to water level

below land surface, in feet

Depth to water level

Daily mean discharge,

below land surface, in feet

in cubic feet per second

Precipitation,

in inches

0

10

20

30

40

50

02203559

37P116

0

2

4

6

8

02226000

Elevation above National

Geodetic Vertical Datum

of 1929, in feet

4

3

0

1

2

0

2

4

6

8

Well 16MM03, White County 

O N D J F M A M J J A S

2010 2011

Depth to water level

below land surface, in feet

Depth to water level

below land surface, in feet

Daily mean discharge,

in cubic feet per second

Precipitation,

in inches

0

200

400

600

800

1,000

02330450

16MM03

0

4

8

12

16

02330450

Elevation above National

Geodetic Vertical Datum

of 1929, in feet

1,550 

1,548 

1,542 

1,544

1,546 

0 

1 

2 

3 

4 

5 

6 

02333500

11FF04

21BB04

12Z001

11AA01

21T001

02223500

02224500

02202600

Black Cr

35P094

13M007

13J004

02356000

10G313

07H002

Dublin

Bainbridge

Chattahoochee

Ocmulgee River

Ogeechee River

Oconee River

Savannah River

River Altamaha

River

Atlantic Ocea

F

n

lint River

Base modified from

U.S. Geological Survey

1:2,000,000-scale digital data

N

0 30 60 MILES

0 30 60 KILOMETERS

Atlanta

ALABAMA

GEORGIA

CAROLINA

SOUTH

FLORIDA

16MM03

02330450

07H003

03PP01

02203559

02226000

02353500

02384500

03568933

37P116

Well 07H003 is 

in Miller County 

in southwestern 

Georgia and is 

completed in the 

surficial aquifer, 

which is an 

unconfined aquifer 

in this area (Peck 

and others, 2011). 

The water level in 

this well generally 

rises rapidly 

during wet periods 

and declines 

slowly during 

dry periods. The 

water level in well 

07H003 responds 

to seasonal 

change similarly 

to streamflow 

at the nearby 

streamgage on 

Ichawaynochaway 

Creek at Milford, Ga. (02353500), which indicates atmospheric, 

surface-water, and groundwater interactions. In the 2011 WY, 

water levels in well 07H003 were below the historical daily 

median for much of the year. For a brief period in January 2011, 

the daily mean water level fell below the historical daily 

minimum water level.

Well 16MM03 is 

in White County in 

northeastern Georgia 

and is completed in the 

crystalline-rock aquifer. 

Water is stored in the 

regolith and fractures, 

and the water level is 

affected by precipitation 

and evapotranspiration 

(Cressler and others, 

1983). Precipitation can 

cause a rapid water-level 

rise in wells tapping 

aquifers overlain by thin 

regolith (Peck and others, 

2011). The water level in 

well 16MM03 responds 

to seasonal change 

similarly to streamflow at 

the nearby streamgage 

on Chattahoochee River 

at Helen, Ga. (02330450), 

which indicates 

atmospheric, surfacewater, and groundwater interactions. The water level in well 16MM03 

remained below the historical daily median for much of the 2011 WY. 

Well 37P116 is in Chatham 

County in southeastern 

Georgia and is completed 

in the surficial aquifer. 

Water levels in this well 

generally rise rapidly 

during wet periods and 

decline slowly during dry 

periods. The water level 

in well 37P116 responds to 

seasonal change similarly 

to streamflow at the nearby 

streamgage on Peacock 

Creek near McIntosh, Ga. 

(02203559), which indicates 

atmospheric, surfacewater, and groundwater 

interactions. The water 

level in well 37P116 

fluctuated above and 

below the historical daily 

minimum for most of the 

2011 WY.

Georgia’s Climate Response Network

The hydrographs presented are for selected wells in 

Georgia with at least five years of continuous data.
5

Walter F

George

Lake

Hartwell Lake

J Strom 

 Thurmond

 Lake

Lake

Sidney

Lanier

West

Point

Lake

Lake Seminole

(Jim Woodruff)

Allatoona

Lake

Lake

Sinclair

Richard B 

 Russell Lake

Atlantic Ocean

Weiss

Lake

Savannah

Atlanta

GEORGIA

SC

AL

FL

EXPLANATION

2011 USGS–GA EPD discrete QW station

Water planning region name

Altamaha

Coastal Georgia

Coosa–North Georgia

Lower Flint–Ochlockonee

Metro North Georgia

 Water Planning District

Middle Chattahoochee

Middle Ocmulgee

Savannah–Upper 

 Ogeechee

Suwannee–Satilla

Upper Flint

Upper Oconee

Lakes and Reservoirs

Major lakes and reservoirs 

throughout Georgia are managed 

primarily by the U.S. Army Corps of 

Engineers and Georgia Power Company 

to provide water for public and industrial 

use, flood protection, power generation, 

wildlife management, and recreation. 

Managing lakes and reservoirs requires 

computer models that rely on USGS 

data to predict changes in climate and 

water demands. 

Lake Sidney Lanier on the 

Chattahoochee River is the primary 

drinking-water source for the Atlanta 

metropolitan area. Lake Sidney Lanier 

is the most upstream reservoir in a series 

of reservoirs that include West Point 

Lake, Walter F. George Lake, and Lake 

Seminole. Lake Lanier had 24 percent 

more outflow than inflow during the 

2011 WY, and the lake elevation fell 

nearly 10 feet from April through 

September. The water-level elevation of 

West Point Lake remained near the top 

of conservation pool until May when 

the lake level dropped nearly 6 feet 

during the remainder of the WY. West 

Point Dam provides flood protection and 

hydroelectric power to Troup County, 

and its construction was authorized by 

the Flood Control Act of 1962 (U.S. 

Army Corps of Engineers, 2012c).

Hartwell Lake is on the border 

between Georgia and South Carolina 

on the Savannah and Tugaloo Rivers. 

Hartwell Lake is the most upstream 

major reservoir on the Savannah River. 

Water is released to the downstream 

reservoirs, Richard B. Russell and 

J. Strom Thurmond. These three lakes 

on the Savannah River are managed by 

the U.S. Army Corps of Engineers for 

water supply, power generation, and 

water-quality needs of the Savannah 

River from below Thurmond Dam 

to Savannah, Ga., and the Atlantic 

Ocean (U.S. Army Corps of Engineers, 

2012a). Hartwell Lake reached full 

pool after having nearly 2.4 times more 

inflow than outflow in March but then 

dropped nearly 8 feet from May through 

September as outflow was 1.7 times 

greater than inflow. 

Allatoona Lake is on the Etowah 

River and is managed by the U.S. 

Army Corps of Engineers. During the 

2011 WY, Allatoona Lake remained 

above or just below the top of conservation pool from October through June. 

By the end of the 2011 WY, the lake 

level was nearly 7 feet below the top 

of conservation pool, as outflow was 

2.4 times greater than inflow from July 

through September.

Water-Quality Monitoring in 

Georgia in Cooperation with the 

Georgia Department of Natural 

Resources Environmental 

Protection Division (EPD)

The USGS, in cooperation with the 

Georgia Department of Natural Resources 

Environmental Protection Division (GaEPD), 

collects nearly 1,000 monthly chemical and 

nutrient samples and about 800 fecal coliform 

samples at 49 long-term monitoring stations 

across the State in addition to data from 

3 continuous water-quality monitors. Four fecal 

coliform samples typically are collected within 

30 days twice during the May-to-October period 

when the standard for water contact applies, and 

then twice during the November-to-April period 

when the alternate standard applies, which 

provides the basis for computing the geometric 

mean fecal coliform density once-quarterly each 

calendar year. In addition, about 200 qualityassurance samples for all constituents are 

collected concurrently to verify the accuracy of 

sampling techniques and analytical methods. 

The USGS provides the GaEPD and 

the public a relevant, nationally consistent 

database of long-term water-quality data, 

which assists the GaEPD in meeting its 

responsibilities under the Clean Water Act, 

including, (1) identifying the beneficial uses 

of surface waters within the State, (2) establishing water-quality standards to maintain 

the full beneficial uses of surface waters, and 

(3) identifying water bodies where stream 

standards are not met and beneficial uses are 

impaired (Grams, 2011). Water-quality data 

for Georgia streams are available on a publically accessible Web site at http://waterdata.

usgs.gov/ga/nwis/qw/.

O N D J F M A M J J A S

2010 2011

Inflow and outflow, in cubic feet per second

Water level elevation, in feet above National Geodetic Vertical Datum of 1929

Alatoona Lake

Hartwell Lake

Lake Sidney Lanier

West Point Lake

Inflow

Outflow

Water

level

Top of conservation

pool

652 

654 

656 

658 

660 

662 

0

50,000

100,000

150,000

200,000

624

626

628

630

632

634

636

0

50,000

100,000

150,000

200,000

250,000

300,000

815

820

825

830

835

840

845

0

20,000

40,000

60,000

80,000

100,000

120,000

50,000

25,000

75,000

100,000

125,000

0 

150,000

1,060

1,065

1,075

1,070

Atlanta
Water-quantity and quality information are 

equally important for insuring adequate water 

availability for human consumption, industrial uses, 

and aquatic ecosystems. Streamflow conditions are 

a primary driver of nonpoint-source-related water 

quality and the most important component affecting 

water quality in streams (Hirsch and others, 2006). 

The USGS–GaEPD discrete water-quality 

sampling program is designed to collect data 

systematically, regardless of hydrologic conditions. 

The graph (top right) shows the water-quality 

sampling efforts by the USGS at Ogeechee River 

near Oliver, Ga., during the 2011 WY. Samples 

were collected throughout the year during periods 

of high and low discharges.

The relations between water-quality 

constituents and discharge are shown in the graph. 

The discrete water-quality sample on February 10 

during a period of higher discharge, when compared 

to samples collected during lower discharge 

on January 27 and May 26, shows a decline in 

specific conductance because of the lower amount 

of dissolved constituents from rainfall runoff. 

Conversely, non-dissolved constituents, such as 

total suspended solids and fecal-coliform bacteria, 

increase with rainfall runoff because these constituents are washed from the land into the stream.

The USGS collected additional water-quality 

samples at Ogeechee River near Oliver on May 26 

after a large fish kill was reported by the GaEPD on 

May 21, which was believed to have been Columnaris disease, a bacterial disease related to environmental stressors, such as non-point source pollutants 

(Georgia Environmental Protection Division, 

2011b). USGS monitoring data can provide useful 

information for understanding the water-quality 

conditions that may be conducive for Columnaris 

outbreaks and could be used for predicting and 

possibly avoiding such outbreaks in the future.

The USGS–GaEPD cooperative program 

collects continuous water-quality data at three sites 

in Georgia, including USGS station 02337170 

Chattahoochee River near Fairburn, Ga. This 

stream reach is classified as “Fishing” under 

Georgia Code 391-3-6-.03 “Water Use Classifications and Water Quality Standards,” which 

requires that the daily mean dissolved oxygen (DO) 

concentrations in the stream remain at or above 

5.0 milligrams per liter (Georgia Environmental 

Protection Division, 2011a). The daily mean DO 

and daily mean discharge for the Chattahoochee 

River near Fairburn, Ga., is shown in graph (bottom 

right) for the 2011 WY. No daily mean DO levels 

fell below the “Fishing” criteria in Georgia streams 

during the 2011 WY.

References

Cressler, C.W., 1964, Geology and groundwater resources of 

Walker County, Georgia: Georgia Geologic Survey Information Circular 63, 144 p.

Cressler, C.W., Thurmond, C.J., and Hester, W.G., 1983, 

Groundwater in the greater Atlanta region, Georgia: 

Georgia Geological Survey Information Circular 63, 15 p.

Georgia Department of Natural Resource, Environmental 

Protection Division, 2011a, Existing rules and corresponding 

laws, 391-3-6 Water quality control: Accessed July 16, 2012, 

at http://www.gaepd.org/Documents/rules_exist.html.

Georgia Department of Natural Resource, Environmental 

Protection Division, 2011b, Ogeechee River fish kill 

information: Accessed July 16, 2012, at http://www.gaepd.

org/Documents/ogeecheefishkill.html.

May 21, 2011, reported fish kill

0

1,000

2,000

3,000

4,000

8/10 9/29 11/18

2010 2011

1/7 2/26 4/17 6/6 7/26 9/14 11/3

Daily mean discharge 

EXPLANATION

Daily mean discharge, in cubic feet per second 

Discrete water-

 quality sample 

Ogeechee River at Ga. 24, near Oliver, Ga. 02202190

Sample date 1/27/11

Discharge 689 ft3

/s

WT 6.2 °C

SC 103 μg/L 

TSS 3.9 mg/L

BacT-FC 40 MPN

 

Sample date 5/26/11

Discharge 178 ft3

/s

WT 27.8 °C

SC 158 μg/L 

TSS 1.3 mg/L

BacT-FC 20 MPN

 

Sample date 2/10/11

Discharge 2,750 ft3

/s

WT 8.0 °C

SC 71 μg/L 

TSS 9.5 mg/L

BacT-FC 170 MPN

 

Discharge In cubic feet per second (ft3/s)

WT Water temperature, in degrees Celsius (° C)

SC Specific conductance, in micrograms per liter (μg/L)

TSS Total suspended solids, in milligrams per liter (mg/L)

BacT-FC Bacteria, total fecal coliform, most probable number 

per 100 milliters of water

Grams, S.C., 2011, Benefits of long-term water-quality 

monitoring in Georgia [abs.], in Carroll, G.D., ed., 

Proceedings of the 2011 Georgia Water Resources 

Conference, April 11–13, 2011, Athens, Georgia: 

Georgia Water Resources Institute, 6. Water informatics, 6.1 Watershed data, 1 p. 

Hirsch, R.M., Hamilton, P.A., and Miller, T.L., 2006, 

U.S. Geological Survey perspective on water-quality 

monitoring and assessment: Journal of Environmental 

Monitoring, v. 8, p. 512–518.

Peck, M.F., Painter, J.A., and Leeth, D.C., 2011, Groundwater conditions and studies in Georgia, 2009–2010: 

U.S. Geological Survey Scientific Investigations 

Report 2009–5048, 83 p., available at http://pubs.

usgs.gov/sir/2011/5048/.

National Oceanic and Atmospheric Administration, 2011, 

National Weather Service advanced hydrologic prediction service, 2011 precipitation maps for Georgia: 

Accessed June 1, 2012, at http://water.weather.gov.

Stooksbury, D.E., 2011, Extreme drought spreads into 

north Georgia, in News to use about Georgia family, 

agricultural consumer & environmental sciences, 

August 31, 2011: University of Georgia, accessed 

June 26, 2012, at http://georgiafaces.caes.uga.edu/

index.cfm?public=viewStory&pk_id=4207.

Torak, L.J., Painter, J.A., and Peck, M.F., 2010, 

Geohydrology of the Aucilla–Suwannee–Ochlockonee River Basin, south-central Georgia and adjacent 

parts of Florida: U.S. Geological Survey Scientific 

Investigations Report 2010–5072, 78 p.

U.S. Army Corps of Engineers, 2012a, Hartwell Dam & 

Lake: U.S. Army Corps of Engineers, Savannah District, accessed June 1, 2012, at http://www.sas.usace.

army.mil/lakes/hartwell/. 

U.S. Army Corps of Engineers, 2012b, Lake elevations, 

inflows and outflows: Accessed June 1, 2012, at 

http://www.sas.usace.army.mil/. 

U.S. Army Corps of Engineers, 2012c, West Point Lake: 

U.S. Army Corps of Engineers, Mobile District, accessed 

June 1, 2012, at http://www.sam.usace.army.mil/

Missions/CivilWorks/Recreation/WestPointLake.aspx. 

U.S. Geological Survey, 1975, Hydrologic unit map 1974, State

of Georgia: U.S. Geological Survey, scale 1:500,000, 1 sheet.

U.S. Geological Survey, 2007, U.S. Geological Survey 

Ground-Water Climate Response Network: U.S. Geological Survey Fact Sheet 2007–3003, 4 p., accessed 

July 1, 2009, at http://pubs.usgs.gov/fs/2007/3003/.

U.S. Geological Survey, 2012a, U.S. Geological Survey 

annual data report for Georgia, water year 2011: 

Accessed June 1, 2012, at http://ga.water.usgs.gov/

publications/pubswdr.html. 

U.S. Geological Survey, 2012b, U.S. Geological Survey 

groundwater watch, Climate Response Network: Accessed 

June 1, 2012, at http://groundwaterwatch.usgs.gov/.

U.S. Geological Survey, 2012c, WaterWatch–Current 

water resources in Georgia: Accessed June 1, 2011, 

at http://waterwatch.usgs.gov/.

6

0 

2,000 

4,000 

6,000 

8,000 

10,000 

12,000 

Daily mean discharge,

in cubic feet per second

Daily mean dissolved oxygen, 

in milligrams per liter

4 

5 

6 

7 

8 

9 

10 

11 

12 

13 

14 

Oct. Nov.

2010 2011

Dec. Jan. Feb.

GaEPD daily mean dissolved oxygen minimum threshold

Mar. Apr. May June July Aug. Sept.

By Andrew E. Knaak, Eric R. Frantz, and 

Michael F. Peck

For more information contact:

Director, USGS Georgia Water Science Center

3039 Amwiler Road, Suite 130

Atlanta, Georgia 30360

770–903–9100

http://ga.water.usgs.gov/