GA EPD

Savannah River Basin Partnership

SC DHEC

SC DNR




Savannah Harbor DO Standard and TMDL

The Federal Clean Water Act and the Georgia Water Quality Control Act authorize the Georgia Environmental Protection Division (GA EPD) to develop water quality standards and to periodically review and update those standards. In 2009, GA EPD proposed new dissolved oxygen criteria for the Savannah Harbor.

In 1986, Georgia EPD proposed a seasonal dissolved oxygen standard for the Savannah Harbor from the Seaboard Coastal Railroad at river mile 24.7 to Fort Pulaski at river mile zero. This stretch of the river is designated as Coastal Fishing. The original Coastal Fishing dissolved oxygen criteria for the Savannah River was disapproved by U.S. Environmental Protection Agency (USEPA) in 1989.

In 2006, a total maximum daily load (TMDL) for dissolved oxygen was established for the Savannah Harbor based on this disapproved criteria. The 2006 TMDL established that all dischargers from Augusta to the Harbor (on the Savannah River and its tributaries) would have to meet an oxygen demanding load of zero. USEPA Savannah Harbor Dissolved Oxygen Total Maximum Daily Load (TMDL) Report [2006]

The 2009 dissolved oxygen criteria was adopted in order for the TMDL to be revised and for GA EPD to move forward with wastewater discharge permit issuances and re-issuances.

In 2007 and 2009, GA EPD worked with the USEPA and the South Carolina Department of Health and Environmental Control (SC DHEC) to develop new dissolved oxygen criteria for the designated use Coastal Fishing. GA EPD investigated a number of possible criteria including a modified freshwater standard and criteria based on a modified Virginia Province standard. GA EPD determined that the modified freshwater standard was most appropriate. These dissolved oxygen criteria are consistent with the South Carolina criteria for the Harbor.

The standard is a daily average of 5.0 mg/L, no less than 4.0 mg/L with a provision that if it is determined that the "natural condition" in the waterbody is less than the values stated above, then the criteria would revert to the "natural condition" and the water quality standard would allow for a 0.1 mg/L deficit from "natural." In addition, up to a 10% deficit will be allowed if it is demonstrated that resident aquatic species shall not be adversely affected.

Much work was done to model the "natural condition" of the waterbody and to compare these numbers with the dissolved oxygen needs of aquatic life in the area.

The Savannah Harbor criteria was approved by USEPA on March 31, 2010 and the public notice for the Revised USEPA Savannah Harbor Dissolved Oxygen Total Maximum Daily Load (TMDL) was issued in May 2010.

 

 


Related Links

Update on Savannah Harbor Dissolved Oxygen Standard & Total Maximum Daily Load: Protecting Savannah Harbor, Jeff Larson, Assistant Branch Chief Georgia EPD Watershed Protection Branch, April 5, 2007 [.pdf]

Georgia Senate Resolution 1063 - Urging the Georgia Environmental Protection Division to implement a new water quality standard for the Savannah Harbor based on sound science that is economically achievable; and for other purposes, 2008.

Georgia Triennial Review Process for New Savannah Harbor DO Water Quality Standard, May 2008 [.pdf]

Georgia's Total Maximum Daily Loads (TMDL) for the Savannah River Basin

South Carolina's Total Maximum Daily Loads (TMDLs)

 

 

 

 

Get Acrobat Reader
Watershed Protection Branch
Georgia Environmental Protection Division
4220 International Parkway, Suite 101
Atlanta, GA 30354

Telephone: 404.675.6232
Fax: 404.675.6246
Copyright © 2008 by the Georgia Department of Natural Resources. All rights reserved.
 
DHEC Bureau of Water
South Carolina Department of Health and Environmental Control
2600 Bull Street
Columbia, SC 29201
Phone: (803) 898-4300
Fax: (803) 898-4215