A wastewater treatment system installed by the city of Montague will help the California city eliminate built-up sludge in an environmentally responsible manner, according to the system’s manufacturer, Absolute Aeration.
The Blue Frog System was installed on May 3 in the first of four wastewater lagoons at the city’s Water & Sewer Department treatment facility. The technology has already begun the process of digesting organic sludge that was built-up in Montague’s lagoons.
Absolute Aeration says its technology is being used in dozens of municipal facilities nationwide and across California.
The traditional method of managing sludge involves dredging lagoons mechanically and disposing of the “biosolids” on farmland, or sending to a landfill. However, these practices are running into increased regulatory restrictions due to the concerns about what is contained in the biosolids, including chemicals, toxic metals and other pathogens.
“We were faced with odor problems as well as a significant sludge buildup in our primary ponds,” said Chris Tyhurst, Supervisor for the Montague Water & Sewer Department, in a statement. “We were planning on having them dredged, which is quite expensive.”
Tyhurst says after seeing the results firsthand in another California city, Montague officials decided to try the Blue Frog System in one of its ponds. “We are hopeful that we will see a substantial reduction in our sludge levels and odor problems in Pond 1. If all goes as planned, the Frogs should continue to digest the incoming load and keep the sludge level at a minimum for many years to come.”
The three Blue Frog circulators installed in Pond 1 at the facility employ a technique called “biodredging,” which uses natural biological processes to enhance organic sludge digestion. The circulators stir up the water to create radial outflowing currents within the lagoon, each moving up to 7 million gallons of wastewater per day. The system selects indigenous microbes already present in the lagoon and incubates new bacteria to populate high-quality microbes.
Over the coming weeks and months, those microbes will “eat” the organic waste that has been stored up and digest incoming organic solids before they have a chance to settle. No chemicals or outside microbes are ever introduced to the lagoon.
Tyhurst said the engineer’s estimate for dredging both ponds was about $700,000, which would have required grant/loan funding because the funds were not available in the city’s 2016 budget.