Ultrasonic Treatment of Algae in a New Jersey Reservoir

A system of ultrasonic buoys was installed in the Canoe Brook Reservoir 1 in Short Hills, N.J., to assess the impact of the system on controlling algae and cyanobacteria in the reservoir. The four buoys operated for five months in spring/summer 2014. The results of the study indicated that the ultrasonic system was effective for controlling algae when the correct ultrasonic program was used. During the testing period, geosmin and methyl isoborneol concentrations were well controlled. Additionally, the average alum dose used by the plant was reduced by 22% compared with the same period in 2013, with improved dissolved air flotation effluent turbidity and combined filter effluent turbidity and an 83% increase in unit filter run volumes. An economic assessment showed the buoys saved approximately $87,800 in operational costs, with a projected simple payback time of 1.8 years for the system. © 2015 American Water Works Association.