In the far north of Crow Wing County, about 30 miles beyond Brainerd, there’s a heart-shaped lake that locals don’t want anyone else to know about.
A stony brook runs through it, pouring in from the northwest shore and exiting over gentle rapids on the southeast, where the water is so clear that one could count the pebbles on the bottom, and the sleek bass guarding their nests, and the schools of minnows swarming, darting and feeding in the shallows.
Mitchell Lake in the town of Fifty Lakes may be the best place in Minnesota to be a fish.
The lake is mostly overlooked by anglers and boaters; its larger neighboring lakes are the ones that have made the greater Brainerd area a destination. But by one metric, Mitchell has every other lake in the state beat. Judging by the health of the fish, Mitchell isn’t just excellent or outstanding, it is perfect.
“It’s incredible,” said Jessica Massure, a research scientist for the Minnesota Department of Natural Resources. “Mitchell Lake is a pretty special spot, really.”
Its score is a testament to both the unique geography around Mitchell and the smart, modest development of the cabin and landowners on its shore.
A few houses are illuminated in the late evening light on Mitchell Lake in Fifty Lakes, Minn. (Anthony Soufflé/The Minnesota Star Tribune)
The DNR started issuing grades and scores to about 3,000 lakes in 2023 to help residents learn about their condition. The grades, for the first time, give residents and local governments an easy to way to look up the status of their lake and compare it to others without needing to scour through reams of pollution data. A [searchable database](https://whaf-lakes.dnr.state.mn.us/) 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.