The alum is applied using precise dosing with the help of computer aboard the barge which tell the pumps how much alum to dispense where on the lake. The alum is injected into the lake 2-3 feet under the surface of the water to maximize treatment effectiveness and the GPS on the barge ensures that there are no gaps in coverage on the lake.
Miss the first project update? Check out the summary of mobilization and the first three days of treatment here. This included assembly of the barge’s application boom, launching the barge into the lake, setting up on-shore storage tanks, confirming the delivery plan for the alum and calibrating the barge computer system for application.
For more information on the alum treatment project for Spring Lake and Upper Prior Lake, visit the alum page on the District’s website here.