Study looks at nature's role

Although Augusta and its urban sprawl are often blamed for pollution in the Savannah River, a new study suggests that Mother Nature also plays a vital role in water quality.


"Sometimes data and perception don't coincide," said research manager Oscar Flite of the Southeastern Natural Sciences Academy, which is midway through its three-year "Savannah River at Risk" study.

The study, focusing on factors that reduce oxygen levels in the river, involves 10 sampling sites from a few miles below Thurmond Dam down to Clyo, Ga., between Augusta and Savannah.

Each monitor collects seven measurements at 15-minute intervals for two years. The resulting 2.4 million data samples are expected to create a comprehensive glimpse into the ecology of the river and factors affecting its water quality.

The profile developed so far hints that Augusta, with its industrial discharges, urban runoff and municipal wastewater sites, doesn't appear to have a huge effect on oxygen levels in the river.

Part of the reason is that the rocky shoals above and below Interstate 20 vastly increase dissolved oxygen levels just before the river flows through Augusta.

"When water comes into Augusta through the shoals, it is super-saturated," Dr. Flite said. "It comes through as 110 percent saturated, so the shoals area literally generates more dissolved oxygen than the water can hold."

Once the water flows through Augusta, oxygen levels decline to 99 percent, before rising again - to 107 percent - as the water pours over New Savannah Bluff Lock and Dam near Augusta Regional Airport.

Once downstream, levels begin to fall.

"At that point, the river is free to flow like a historic river would," he said. "It snakes back and forth through the Coastal Plain."

That natural meandering path creates cutbanks where silt, mud, decaying wood and trees and other natural organic materials are deposited into the channel.

Such materials can reduce dissolved oxygen levels, which fell to 91 percent near the Savannah River Site property.

The findings are important because regulatory agencies such as the U.S. Environmental Protection Agency have focused on measured discharges of oxygen-demanding materials in Augusta as a potential contributor to low oxygen levels in Savannah Harbor.

Because of those low levels in the harbor, EPA has proposed limits on measured discharges in Augusta in hopes of remedying the downstream deficiencies.

"We think it is necessary to characterize those natural contributions, too," he said. "Floodplains are major sources of organic material, and they add a lot of material to a river."

The study, which will continue for another 18 months, also is expected to shed new light on the effects of temperature changes, chemical discharges, storms and flood events and other factors.

Reach Rob Pavey at (706) 868-1222, ext. 119, or


WHAT IS IT? A three-year, $2 million study by the Southeastern Natural Sciences Academy, an Augusta-based research and education group that also operates Phinizy Swamp Nature Park.

OBJECTIVES: Using sampling devices that take measurements every 15 minutes along 154 miles of river, scientists plan to gather 2.4 million data points to create a comprehensive glimpse into the river's ecology and define factors that affect its water quality.

WHY IT'S IMPORTANT: The U.S. Environmental Protection Agency and other regulators often use known discharges from urban industries and wastewater plants to set policy and pollution limits, but more data is needed on the effect of floods and natural factors in water quality.