One of the three installed MPC buoys is shown near the intake of Gainesville’s Riverside Water Treatment Plant.
The City of Gainesville is hoping to use a different kind of wave on Lake Lanier to combat taste and odor issues with its treated water.
For months residents across metro Atlanta including Gainesville have complained about an “earthy” or “dirt” taste to their water. Water officials have conducted “extensive” and recurring testing showing the water is safe for drinking and the issue is one of aesthetics.
“As the 2025 taste and odor event continued, DWR staff continuously searched for additional remedies,” said Gainesville Water Resources Director Linda MacGregor via the city’s Facebook page.
The city settled on Netherlands-based LG Sonic, which she described as “pioneers in ultrasonic algae control.”
“We sought the input of national experts who identified (LG Sonic) as an option worth testing.”
The city said the science behind LG Sonic’s ultrasonic technology has the potential to reduce algae by 95 percent without chemicals, stopping algae growth long-term without harming people, pets, other aquatic life or the lake itself.
In December 2025 Gainesville partnered with the company to place three “MPC’ buoys near its Riverside Water Treatment Plant on north Lake Lanier. MPC stands for monitor, predict and control.
The city says the buoys emit low-power ultrasound waves in the top water layer that block algae’s access to sunlight and nutrients, causing the algae to sink and die off, decomposing naturally. This is made possible by generating a constant pressure cycle around the algal cells, which interferes with the algae’s buoyancy, or its ability to reach the surface for sunlight and the bottom for nutrients. Instead, algae remains suspended between the two – deprived of the optimal environment needed to thrive and multiply.
“By emitting sound waves that disrupt the buoyancy of algae, you’re preventing them from releasing the compounds that cause the musty taste and odor issues,” MacGregor said.
She said the buoys are equipped with real-time water quality monitoring. “They provide an overview of our water quality by collecting the following parameters every 10 minutes: chlorophyll α (green algae), phycocyanin (blue-green algae), pH, turbidity, dissolved oxygen and temperature. Data is key when it comes to understanding this complex natural phenomenon.”
Gainesville is the first in the state of Georgia to use this technology, but not the first to report taste and odor challenges caused by algae blooms.
“All utilities withdrawing water from both Lake Lanier and the Chattahoochee River are expressing these issues to varying degrees,” MacGregor said. “Also, other lakes have experienced identical issues this year, more so than other years.”
According to its website, LG Sonic serves 12 industries and has a presence in over 55 countries – clients who wish to control algae sustainably and maintain aquatic environments devoid of chemicals or other contaminants.
The following entities have turned to LG Sonic following similar complaints of foul taste and odor issues: Town of Johnstown, Colo.; American Water New Jersey, in Short Hills, N.J.; Missouri and Minnesota. Other MPC-Buoy deployments around the world help address algae concerns beyond drinking water, like recreation, hydropower, irrigation and more.
Gainesville’s MPC-Buoys, secured under a six-month rent-to-own contract, were deployed in the immediate vicinity of the water intake at Riverside Water Treatment Plant.
“The sound waves (active component) extend out about 800 meters, or 2,600 feet,” MacGregor said. “We are pilot testing whether this technology effectively impacts the water that Gainesville withdraws. For now, our pilot test will not impact all of Lake Lanier, just the area surrounding the Riverside WTP.”
The city will evaluate the MPC-Buoys’ impact before deciding whether to deploy additional units to other parts of Lake Lanier that would benefit Gainesville’s drinking water system. Until then, minimal maintenance is required (roughly every six months), which is covered by LG Sonic for one year per the City’s contract.
“We want to remedy the issue just as badly as residents want us to remedy the issue,” MacGregor said. “DWR staff have been working around the clock to address taste and odor concerns with every known solution, but unprecedented algae levels in Lake Lanier are proving more difficult to treat than in years past.”
For additional information regarding taste and odor, visit www.gainesville.org.
To learn more about LG Sonic, visit www.lgsonic.com.
Photos: by Vicki and Alan Hope
