Etowah River Basin Profile

The Etowah River Basin is located in the northwestern portion of the District and represents 24 percent of its total area and 63 percent of the overall Hydrologic Unit Code (HUC)-8 Basin area. With 1,183 square miles, it is the largest river basin in the District.

Allatoona Lake, located on the mainstem of the Etowah River in the center of this basin, is managed by the United States Army Corps of Engineers (Corps) and is a significant recreational destination and water supply source within the District, state, and Southeast U.S.

There are 99 unique soil components in the Etowah basin that overlap with the District. These soil components were mapped using the USDA's Gridded National Soil Survey Geographic Database ( gNATSGO ). Scroll to the map below to explore where each of these components are located.

Protected species include all species listed as threatened or endangered by the U.S. Fish and Wildlife Service (USFWS) and those listed as endangered, threatened, or rare by the State of Georgia. The current listings of these endangered species, including their status, range, and habitat, can be accessed via the USFWS’s automated Information, Planning and Conservation System (IPaC,   http://ecos.fws.gov/ipac/  ) or  Georgia's Biodiversity Portal .

The Metro Water District is home to a number of species that are considered threatened or endangered. Protecting watershed health is more than protecting water quality; it also includes protection of biological resources. Within the District, there are a number of protected animal species that spend all or part of their life cycle in rivers and streams or depend on streams for a significant portion of their life history. There are 27 protected species potentially found within the counties that intersect the Etowah River Basin of the District. View the table to the right for species status.

Trout streams are classified in accordance with the primary and secondary designations and criteria defined in Section 15 of Georgia’s Water Use Classifications and Water Quality Standards (391-3-6-.03). Streams designated as primary trout streams are waters supporting a self-sustaining population of rainbow, brown or brook trout. Streams designated as secondary trout streams are those with no evidence of natural trout reproduction but are capable of supporting trout throughout the year.

Seasonal secondary trout streams are located in Boston Creek in Bartow County and Cherokee County upstream of Georgia Highway 20. Seasonal secondary trout streams are located on Pumpkinvine Creek and Raccoon Creek in Paulding County. Year-round trout streams are located in the following Bartow County streams: Connesena Creek, Dykes Creek, Pine Log Creek, Pyle Creek, Salacoa Creek, Spring Creek, Stamp Creek upstream from Bartow County Road 269, Toms Creek upstream from Bartow County Road 82, Two Run Creek, and Ward Creek. Year-round trout streams are located in the following Cherokee County streams: Bluff Creek, Pine Log Creek, Salacoa Creek, Soap Creek, Stamp Creek, and Wiley Creek. Year-round trout streams are located in the following Paulding County streams: Possum Creek, Powder Creek, Pyle Creek, Thompson Creek, and Ward Creek.

 Click here  to visit Georgia Department of Natural Resource's Web App of trout streams.

Draining the northwestern portion of the District, the central portion of the Etowah River Basin is bisected by Interstates 75 and 575, while its headwaters are crossed by Georgia 19 (GA 400) in northern Forsyth County. It also includes major east-west corridors, such as Georgia Highways 20 and 92 and the corresponding development that accompanies them.

Overall, 28 percent of the Etowah River Basin within the District is developed, 54 percent of the area is forested, and 18 percent of the area falls within the remaining land cover classes found in the following pie chart.

The level of watershed imperviousness has long been linked to impacts on changes in hydrologic regimes that lead to increased intensity and frequency of peak stormwater flows, which affect stream stability, water quality, and aquatic habitat and biotic community integrity. In general, the most sensitive aquatic organisms are affected at impervious levels greater than 10 percent.

Impervious surfaces (such as roofs, streets, parking lots) have a significantly different hydrologic response from pervious surfaces (lawns, forests). Therefore, it is important to clearly define terms and assumptions related to the calculation of pervious and impervious areas for the purposes of watershed management.

“Total impervious area” quantifies all of the land surfaces impervious to rainfall for the particular land cover category while “effective impervious area” (EIA) refers to the directly connected impervious area used for water quality and stormwater conveyance modeling.

For the 2022 District-wide Plan, the EIA of the HUC-1 subwatersheds within the District was calculated using a mathematical model developed by Sutherland for U.S. Environmental Protection Agency (EPA) based on land cover data from the 2019 USGS National Land Cover Database.

Of the 64 HUC-12s within the District portion of Etowah River Basin, 13 had an EIA of greater than 10 percent, primarily those HUCs that either straddle a major transportation corridor such as the I-75/I-575 interchange or the HUCs that include the more densely urbanized areas of the cities of Acworth and Cartersville.

Scroll to the map below to explore the Etowah River Basin's spatial distribution of land cover classes, undeveloped and developed area, and effective impervious area.

To explore land use and imperviousness with the ability to toggle layers on and off while zoomed in, please visit  this  web app.

The Etowah River Basin is a primary drinking water supply source for several of the District counties including Bartow, Cherokee, Cobb, Forsyth, and Paulding. Withdrawals from this basin provide approximately 14 percent of the District’s total public water supplies.

Recognizing the linkage between watershed management and water quality for water supply, the Georgia Department of Natural Resources (GADNR) Rule 391-3-16-.01 includes environmental planning criteria (or Part V criteria) to protect natural resources, such as wetlands, stream buffers, water supply watershed areas, groundwater recharge areas, protected rivers, and protected mountains.

A small water supply watershed is a watershed that has less than 100 square miles of land within the drainage basin upstream of a water supply reservoir. In this context, a water supply reservoir is a governmentally owned impoundment of water for the primary purpose of providing water to one or more governmentally owned public drinking water systems, which excludes the multipurpose reservoirs owned by the United States Army Corps of Engineers.

GADNR Rule 391-3-16-.01(7) requires 100-foot undisturbed buffers and 150-foot impervious surface setbacks for streams in small water supply watersheds within 7 miles upstream of water supply intakes and within 7 miles upstream of water supply reservoirs, excluding federal reservoirs. That portion of a small water supply watershed that includes the corridors of streams within a 7‑mile radius upstream of a governmentally owned public drinking water supply intake or a non‑federal water supply reservoir is called the protected small water supply watershed.

To facilitate implementation of GADNR Rule 391-3-16-.01(7) and Action Item Integrated-7, all areas of small water supply watersheds that are subject to protection through additional buffers and setbacks have been mapped for all local governments within the District. Additional information and guidance can be found on the District Technical Assistance webpage in a memorandum titled, “ District TAP Memo – Integrated-7 Additional Buffers in Small Water Supply Watersheds .”

The Etowah River Basin has 3 square miles of protected small water supply watersheds in Paulding County as shown in the map below.

Permitted Wastewater Facility Service Areas

There are 19 municipal wastewater treatment facility in the Etowah River Basin with a permitted capacity of 74.9 maximum monthly flow – million gallons per day (MMF-MGD).

Additionally, the Etowah River Basin has 27 non-municipal wastewater treatment facilities with a permitted capacity of 11.3 MMF-MGD.

Combined-sewer Overflow Areas

There are no combined-sewer overflow areas in the Etowah River Basin.

The Georgia EPD establishes water quality standards for the state’s surface waters. Section 303(d) of the federal Clean Water Act requires that all states list water bodies that do not meet water quality standards. The Georgia EPD publishes a biennial list of streams that do not meet State water quality standards, referred to as the  305(b)/303(d)list.  If a water body does not support its designated use (drinking, recreation, fishing, wild/scenic rivers, or coastal fishing) because conditions violate water quality standards, it is considered an “impaired” stream or water body. Explore the  Water Quality in Georgia StoryMap  by Georgia EPD for summaries of the 305(b)/303(d) Integrated Report and interactive maps of the related data.

The District portion of the Etowah River Basin contains 2,593 stream miles, 559 of which were assessed for impairments. A total of 274 stream miles, 11 percent of total streams or 49 percent of assessed streams, did not meet State water quality standards based on the 2024 303(d) list. Criteria violated include biota, dissolved oxygen, E. coli, and fish consumption guidance.

Biota listings typically indicate high sediment loads in streams, which decreases habitat quality for benthic macroinvertebrates and fish. Sediment sources include runoff from construction sites as well as from streambank erosion due to accelerated streamflow velocities from impervious cover associated with urbanization.

Allatoona Reservoir has a designated use of Recreation and Drinking Water with corresponding chlorophyll a and total nitrogen criteria. A portion of the reservoir, the Etowah River arm, is pending assessment of the designated uses of Recreation and Drinking Water by meeting State water quality standards for chlorophyll a.

TMDLs and TMDL Implementation Plans have been developed to help jurisdictions address impaired streams and specific parameters of concern. More information on specific TMDLs in the Etowah River Basin can be found on the Georgia EPD website  https://epd.georgia.gov/total-maximum-daily-loadings 

The following management issues and recommended strategies are identified in the 2022 Water Resources Management Plan, Appendix A. They provide watershed improvement guidance to local jurisdictions by describing the potential causes and potential solutions to watershed issues in the river basin.

Source Water Quality

Issue Description:

Source water watershed protection of Allatoona Lake, Etowah River, and small water supply watersheds

Recommended Strategies:

• Implement source water protection measures in all subwatersheds draining to Allatoona Lake
• Continue collaborative efforts in small drinking water supply watersheds to protect the viability of these supplies

Nutrient Loading

Issue Description:

• Portions of Allatoona Lake are pending assessment for chlorophyll a standards; therefore, Georgia EPD is in the process of reevaluating the chlorophyll a criteria

Recommended Strategies:

• Implement post-construction stormwater controls and infiltration practices to reduce NPS pollutants associated with multiple land uses, particularly suburban/urban and agricultural
• Educate the public on NPS pollution reduction and proper fertilizer application and the impacts of excess nutrients on the lake and local economy
• Coordinate with Georgia EPD NPS Program to develop nutrient management plans and strategies to reduce nutrient loading from animal feeding operations in concentrated production regions, as funding allows
• Participate in efforts to educate agricultural stakeholders about the importance of implementing the Best Management Practices for Georgia Agriculture Manual for animal production facilities (poultry) and grazing operations
• Coordinate with Georgia Department of Agriculture Livestock/Poultry Section on inspections, complaint investigations, nutrient management plan reviews, permit administrative support and enforcement assistance (Georgia EPD, 2014)

Increases in Impervious Cover

Issue Description:

Increases in impervious cover can lead to a change in the hydrologic regime of a watershed by causing more intense, high-velocity stormwater flows and increased erosion and sedimentation

Recommended Strategies:

• Nonpoint source pollution management
• Adopt and enforce the post-construction stormwater control ordinance and use of Georgia Stormwater Management Manual design standards
• Watershed improvement projects, such as stream restoration and bank stabilization, are recommended in areas to reduce instream sediment load contributions

Inadequate Stormwater Controls on Existing Impervious Cover

Issue Description:

• Much of the development in the basin occurred prior to current Georgia Stormwater Management Manual design standards
• Limited resources and cost of maintaining and repairing stormwater infrastructure
• Varying local strategies of funding stormwater management

Recommended Strategies:

• Implement an asset management program to identify and prioritize maintenance and capital improvement projects to maximize benefit
• Consider updating stormwater controls during redevelopment
• Identify opportunities for watershed improvement projects to retrofit or install updated stormwater controls, green infrastructure, stormwater treatment or other controls
• Consider dedicated funding sources, such as stormwater utilities, and seek out opportunities for grants, loans, and partnerships

Aquatic Resources

Issue Description:

Several secondary trout streams are located within the Etowah River Basin

Recommended Strategies:

• Balancing nonpoint source temperature inputs from tributaries with natural cold water base flows to meet secondary trout stream criteria

Biota TMDLs

Issue Description:

• 20% of assessed instream fish communities and 7% of the benthic macroinvertebrate communities are impaired
• Biota impairment in this basin is the result of high sediment loads, primarily associated with existing development with inadequate stormwater controls, which is a concern for drinking water source supplies, biota, and recreation

Recommended Strategies:

• Enforce post-construction stormwater ordinance on new development and seek opportunities to retrofit stormwater controls to maximize water quality and channel protection
• Recommend watershed improvement projects, such as stream restoration and streambank stabilization, in areas with failing stream banks to reduce instream sediment load contributions

Bacteria TMDLs

Issue Description:

29% of assessed stream segments in the Etowah River Basin (within the District) are listed for fecal coliform

Recommended Strategies:

• Identify bacteria sources through inspections, monitoring, source tracing and stream walks
• Educate public on pollution prevention, proper septic system maintenance and reporting a potential illicit discharge
• Address fecal coliform bacteria contributions from SSOs
• Address bacteria loads from agricultural sources as they are identified
• Perform regular maintenance to ensure proper functioning of decentralized systems (such as septic tanks) near the Etowah River and Allatoona Lake

Lake Management

Issue Description:

Allatoona Lake is the largest lake within this basin. There are 303(d) assessments pending for potential chlorophyll (a) exceedances in the Little River Embayment. There are also other publicly and privately held and managed lakes that play a significant role in meeting designated uses, water supply needs, and downstream hydrologic regimes

Recommended Strategies:

• Develop a central inventory of lakes, ownership, and management practices to facilitate pollutant source identification both up and downstream of the lake
• Coordinate available water quality data and management activities for inventoried lakes
• Implement shoreline protection and upstream sediment management to prevent excessive nutrients and sedimentation within the lake
• Facilitate proper maintenance and management, particularly of small lakes by providing resources, links, or other materials to assist with periodic activities such as inspections, water quality sampling or dredging
• Conduct public education and involvement activities to promote watershed stewardship to protect lake quality