Main Canal Magnacide Application

We will be treating the main canal with Magnacide H aquatic herbicide to control algae and aquatic weeds from Little Bow to Scope reservoirs Friday June 5 and Saturday June 6, 2026. The amount of Magnacide we use is directly proportional to the flow in the canal, so lower flows during treatments reduce our costs. Magnacide is expensive, and we have spent over $1 million to purchase the amount needed in a year when most treatments were done at high flows. A large portion of our total Magnacide costs are incurred during our two scheduled treatments of this reach of the main canal.

To reduce costs, we encourage irrigators served by this reach of the main canal, including pipelines and laterals which are supplied from the canal, to minimize their irrigation on June 5. On June 6 irrigators in Ranges 18, 19, and 20 could resume normal irrigation, but irrigators in Ranges 14-17 should try to delay normal irrigation until June 7.

It is helpful if all irrigators communicate with their ditchriders and reduce irrigation when their canals are scheduled for Magnacide treatments, especially on larger canals.