WHAT WE DO
Alum Treatment
A proven, science-based treatment that binds legacy phosphorus already sitting in lake sediment so it can no longer fuel algae blooms.
What is Alum?
Aluminum sulfate (alum) is applied at the lake surface, where it forms a flocculent floc that settles to the bottom and binds phosphorus. Done correctly, the effect can last many years.
Alum treats the symptoms of decades of past loading — pairing it with watershed work treats the cause.
Long Lake history
MCWD has implemented alum applications in 1996 to address legacy phosphorus, with monitoring before and after to measure water clarity, total phosphorus, and chlorophyll-a response.
LLWA is currently working with the MCWD on exploring summer data collection to better understand existing conditions and gather preliminary data to inform future decisions about in-lake alum treatment as part of a balanced, two-pronged approach that addresses both external and internal load priorities. Once the data collection and feasibility information is released, LLWA will evaluate the costs, effectiveness and potential timing of any proposed alum project research and/or projects, coordinating our efforts with the MCWD. Stay tuned for next steps!