By Janet Kauffman
Bean/Tiffin Watershed Coalition
Recently, in a survey about Bean Creek, the Lenawee Conservation District asked, “Do you think Bean Creek should be a county drain?” Bean Creek, our beautiful natural stream? Bean Creek, flowing naturally from Devils Lake to the Ohio line? Bean Creek, with its abundant fish and mussels, some very rare?
The answer, for many many reasons, is “No, Bean Creek should not now, not ever, be a county drain.” The River Raisin is not a county drain. (Many of the River Raisin’s tributaries are drains, as are some of Bean Creek’s tributaries in flatter areas to the south.)
But Bean Creek and the River Raisin are natural streams and always have been. Their coldwater tributaries are natural streams. It’s important to keep them that way.
In many places the Bean looks like a river up north, thanks to the forested banks, the riffles and rapids, the native shrubs like nannyberry and witch hazel growing along its edges, bending over the water, shading and cooling the stream for 17 species of freshwater mussels, for dozens of species of fish, and for the thousands and thousands of aquatic insects that are food for fish.
Bean Creek’s coldwater tributaries are a rarity in this part of Michigan. Flowing out of the uplands of Hillsdale County, the water is cold enough for fish like trout, documented in the past, and for mottled sculpin and an endangered fish—the redside dace (see it at www.beancreekwatershed.org)—documented in recent years just north of Hudson.
A drain can be cleared, it can be dredged, its banks can be scraped clean. The cost isn’t just the cost people pay for drain work, although those assessments have just doubled with a new Michigan law.
Even more, we could pay an immeasurable cost—the loss of a rare natural stream, its natural flow and function.
The Tangle, the Tea
It’s well-known how trees and shrubs along streams hold the banks in place with their roots, how vegetation holds back sediment. But in many ways people are just discovering how natural streams work, how they feed the whole river system.
The tangle, the overhanging shrubs and trees are even more important than you might guess.
Research at the Stroud Water Research Center has recently revolutionized our understanding of natural streams, especially forested headwater streams like the Bean. Studies of these streams show how solar energy in the form of leaves provides the essential food, a “watershed tea,” that flows downstream and nourishes the whole length of a river system.
Here’s how that “tea” is brewed: leaves and overhanging woody debris fall into the stream and this leaf litter—with attached microbes and aquatic insects collecting, scraping and shredding the organic material—generates a flow of energy that feeds all life in the river downstream, rivers that are too wide to have their own leaves overhead, such as the Maumee River.
When you know how rivers and natural streams work, you see them differently. Instead of a tangle of brush to chop or remove, you see networks of roots holding soil, preventing erosion. You see the cooling canopy. Instead of woody debris in the water as a mess or a problem, you see organic material to feed fish and everything downstream as well.
There’s food, energy and abundant life in leaf litter and woody debris, in the sand bars that build and shift in water, in the cobbles and riffles of a natural stream. Bean Creek has them all. Let’s keep it that way—a rare and beautiful stream, flowing naturally.