Clarkesville explains recent water taste and odor problems

CLARKESVILLE, Ga. — Clarkesville water officials say seasonal changes in reservoir conditions contributed to an earthy taste and odor that recently affected the city’s drinking water.

Joe Deputy, administrator of the city’s Environmental Services Group, addressed the issue during the Nov. 3 City Council meeting, explaining the steps staff took to identify and address the problem.

Deputy said the city began noticing the unusual taste and smell several weeks ago. Initially reported in downtown Clarkesville, the issue eventually spread to other parts of the water system.

After investigating at the water plant, staff determined the problem was associated with what is known as reservoir turnover.

“This happens anytime you hit real hard swings in temperature,” Deputy said.

He said unusually warm daytime temperatures, combined with a lack of rainfall, contributed to the conditions. Lower rainfall reduced the flow of water in the river, which Deputy said also lowered dissolved oxygen levels.

The city took several steps to address the problem, beginning with its treatment process.

Deputy said the city uses copper sulfate to pretreat water for algae and organic material entering the reservoir. Staff also cleaned the raw-water intake, where silt, sticks, leaves and other organic debris had accumulated.

“Raw water intake over the course of the year starts accumulating silt, but with that comes sticks and leaves and other debris that are considered organic,” he said.

Deputy said crews cleaned the intake down to the concrete. The city then brought in activated carbon, which was added during the treatment process to help remove compounds responsible for taste and odor.

The city’s gravity filters are not designed to remove those particular issues, Deputy explained, making activated carbon an additional treatment step.

“Anybody activated carbon will remove most contaminants from any water,” he said, cautioning that staff must carefully control how much is used.

Deputy said the additional treatment appeared to help reduce the taste and odor.

The city plans to continue monitoring and testing the water as staff work to identify and address the conditions earlier if they occur again.

Deputy acknowledged that predicting reservoir turnover can be difficult because it is driven by changing environmental conditions.

“We’ll try to continue testing. We’re trying to catch these things on the front side,” he said.

Residents who continue to notice unusual taste or odor in their water are encouraged to contact the city and identify the affected neighborhood or area. Deputy said staff may be able to flush water lines in specific locations to help alleviate the problem.

“We would ask that anybody still experiencing these issues locally or in their neighborhood, maybe more specifically, we could do some flushing in that immediate area and try to alleviate those things,” he said.

Deputy said larger communities that draw drinking water from reservoirs, including those supplied by Lake Lanier and Lake Allatoona, regularly deal with similar seasonal taste-and-odor issues.

He said the problem was unusual for Clarkesville at this level.

“This is probably the first time in my eight years that we’ve had to deal with this at this level,” Deputy said.

He also distinguished the recent taste-and-odor problem from water discoloration that has occurred in the past. Deputy said those incidents have generally been associated with water-line breaks, when increased water velocity can scour material from the inside of pipes.

“This is something entirely different,” he said.

The city previously said its drinking water remained safe despite the unusual taste and odor. The issue was attributed to seasonal reservoir conditions rather than a water-quality safety concern.

Deputy thanked council members and said the city would continue monitoring the system in hopes of preventing a recurrence.