Forget bulldozers and giant shovels. When it comes to gouging away large swaths of land, man-made implements pale in comparison to a river.
Mankato is getting schooled in that reality these days. The Minnesota River has over the past decade or so wiped away more than 50 feet of earth between it and Well No. 15 in Land of Memories Park, and it shows no signs of resting.
The river is now within 15 feet of the municipal well, which reaches into the sands under the Minnesota and Blue Earth rivers to provide some 30% of Mankato’s water supply. With the river chronically high for more than two years, it might not take much — one big storm, a rapid snowmelt — for the river to claim those 15 feet and fatally compromise the well.
Losing the well would likely force the city to impose a watering ban. It would also mean relying more heavily on other wells that draw from the Mount Simon aquifer, a water supply for a large portion of the state that is already being drawn upon too heavily. The risk of depleting the Mount Simon aquifer makes preserving Mankato’s well worthy of the state’s attention.
The threat to the well underscores the issues of runoff. Whether from municipal storm sewers or farmland tilling and ditches, water is getting to the Minnesota faster and in greater quantity than in the past. The water that flows past Mankato comes from 37 counties. This too is emphatically a state and regional issue, not one Mankato can be expected to resolve on its own.
The city is revamping its water-quality proposal to the 2020 state Legislature to focus on stabilizing its riverbanks. That’s well and good, but we fear that by the time the Legislature acts on a capital projects bill — and such legislation has repeatedly proven difficult to pass in an era of divided state government — Well No. 15 may be lost.
That would be a problem for Mankato — and for everybody else in southern Minnesota.