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History-making phosphorus filter installed


Crystal Waters Project is excited to announce the installation of an iron-enhanced sand filter at the mouth of a tile line that empties into County Ditch 56. It is located south of Lake Crystal along the ditch near the horse arena at Jones Park.

 A very efficient way to remove phosphorus, this is how the filter works: As water from the drainage tile moves over the filter, the iron acts as a natural magnet for phosphorus, trapping it and separating it from the water. The iron-sand medium ensures that a significant portion of the phosphorus in the discharge will not enter the ditch, which flows directly into Crystal Lake. Less phosphorus entering the lake will result in less algae and improved water quality. 

While there are other iron-sand filters in Minnesota, this is the first to be installed at the end of a field’s drainage tile. Data will be collected to gauge the filter’s efficacy.

This was a cooperative effort supported by several groups: ISG, Blue Earth County SWCD, Blue Earth County Ditch Authority, Gustafson Drainage, Sandt Farms, the City of Lake Crystal and Crystal Waters Project. 

To watch a video clip shown on KEYC 12 on November 14, 2019, please use this link: