James Rada, Jr.
The sonic algae control system has proven itself, both in reducing costs and controlling algae, in Rainbow Lake in Emmitsburg. Even so, there is room for improvement.
“We did see a significant improvement in water quality,” Emmitsburg Town Manager Cathy Willets told the commissioners.
She presented town staff’s comparison of the water system between April and December in 2016, before the LG Sonic algae control system was installed, and the same time frame in 2017, after it was installed.
Backwashes: Although the number of backwashes of the system was expected to decrease, they increased 9 percent (from an average of 10 per day to 10.87 per day).
Backwash water usage: The increase in backwashes was offset by the amount of water wasted to make clean water. This decreased from 19.71 percent in 2016 to 14.08 percent last year. This created a savings of 384,888 gallons of water monthly or the equivalent of 50.5 taps.
Average flow for the lake: The town exceeded its target flow for Rainbow Lake with the new system. The target had been 162,000 gallons a day. It was actually 159,600 gallons.
Overtime: Overtime at the water plant was reduced by 31 percent or nearly $3,000.
Chemical costs: Although some chemical usage increased (DE and coagulants), the overall chemical costs decreased from $33,533 in 2016 to $24,440 in 2017.
One problem that is being worked on by LG Sonic is improving the system’s effect on brown algae. “The device performed excellent when dealing with blue-green algae,” Willets said. “It struggled in the fall with brown algae. We are working on ways to combat brown algae more.”
The new system may actually have put the town ahead of the curve in one regard. The Environmental Protection Agency is monitoring algae toxins to decide on whether federal standards need to be set. The LG Sonic system has reduced the toxins in Rainbow Lake without using lots of potentially harmful chemicals.