Pine River Watershed Alliance recognizes the work that a number of organizations are doing to reduce phosphorus in Island-Loon Lake on the Whitefish Chain of Lakes. The organizations involved include the City of Crosslake, Crow Wing County, Pine River Watershed Alliance, the Crosslakers, Crow Wing Soil and Water Conservation District, and the Land and Waters Preservation Trust.
In 2015, the MN DNR completed research on Lakes of Phosphorus Sensitivity Significance. Out of 2,795 lakes studied statewide, Island‑Loon Lake ranked in the top 14 for sensitivity. In 2017, RMB Labs determined that Island‑Loon Lake has a declining trend in water clarity 1992 ‑ 2016. Water clarity has declined 48 inches over 14 years or an average loss of 3.5 inches of clarity per year.
In the City of Crosslake, CSAH 66 has a number of sections that have curbs and gutters that collect the runoff from the road and some adjacent land and funnel that runoff, untreated, into the Whitefish Chain of Lakes — specifically, Island‑Loon Lake and Crosslake along with the Pine River. The project intercepts the flow of runoff water along CSAH 66 and Manhattan Point Blvd that comprises a mini-watershed of 42.6 acres that currently runs directly into Loon Lake
A system of three hydrodynamic mechanical filters and a holding pond will reduce six pounds of phosphorus and 1.2 tons of sediment per year from entering Island‑Loon Lake (Whitefish Chain). The system was designed by Widseth Smith Nolting, engineering firm for the City of Crosslake.
Water clarity and phosphorus levels will be monitored to determine the effectiveness of the filtration and holding pond system so that information can be applied to other sites along CSAH 66 through Crosslake where runoff goes directly into one of the lakes or the Pine River. The US Forest Service has identified the Pine River as Minnesota’s number one water protection river for the Twin Cities drinking water supply.