The City of Eau Claire is sponsoring a Lake Management Planning Implementation project aimed to control internal sediment phosphorus loading in Halfmoon Lake by applying alum. The lake received an initial AL treatment in 2011 and was effective at maintaining TP WQ goals for three years, however after five years the effects have diminished. The initial alum treatment dosage was adequate however the floc did not sink into the upper sediment due to higher bulk density characteristics allowing upward P diffusion and decreasing binding efficiency of phosphorus. The second treatment is needed to bind available TP limiting the amount available to algae uptake. The City continues to address other sources of TP including stormwater management, rain gardens etc.

The City of Eau Claire is sponsoring a Lake Management Planning Implementation project aimed to control internal sediment phosphorus loading in Halfmoon Lake by applying alum. The lake received an initial AL treatment in 2011 and was effective at maintaining TP WQ goals for three years, however after five years the effects have diminished. The initial alum treatment dosage was adequate however the floc did not sink into the upper sediment due to higher bulk density characteristics allowing upward P diffusion and decreasing binding efficiency of phosphorus.