One of the unhealthiest lakes in Minnesota is 5½ miles long and stretches into three pools that, when viewed from above, look like a wasp about to sting. It’s a few miles north of the Iowa border in the city of Worthington, where its waters, cloudy with muck and festering algae, choke out the sun.
In Lake Ocheda few plants grow. Only carp seem to thrive, turning over the lake bottom again and again, swarming and splashing in an otherwise barren basin of bacteria.
The lake was loved once. And clear.
Through 150 years of decisions great and small, Lake Ocheda became one of the most degraded and polluted lakes measured in Minnesota.
Its future may now rely on a somewhat desperate plan to completely drain the lake and keep it dry for two years, in the hope that cleaner water will refill it.
The transfusion, however, won’t save Ocheda forever. Without major changes to the ditches and drainage pipes that surround it, experts say the lake will eventually slip back into a state of filth.
The Minnesota Department of Natural Resources started issuing grades and scores to about 3,000 lakes in 2023. The grades, for the first time, give residents and local governments an easy to way to look up the condition of their lake and compare it to others without needing to scour through reams of pollution data. A searchable database of every lake with a grade was built by the DNR’s Watershed Health Assessment Framework program.
The letter grade, from A+ to F — based on a 0 to 100 score — denotes the health of a lake and how far it has fallen from what a lake of its size, depth and region should be. A lake’s score is based on how polluted it is, whether fish and native plants survive, and the development on its shoreline and watershed.