U of M builds a stream from the ground up


The trouble with studying rivers is that it's hard to get them to do what you want. Especially if you're just a graduate student, like John Gaffney.

But a new outdoor facility at the St. Anthony Falls Laboratory in Minneapolis is giving researchers like Gaffney a chance to start a stream from scratch.

"I spent a little of my time this summer out here, doing stuff with the riffle sections. These are the sections here where...it looks like the water is moving a little faster and it's kind of ripple on top. I designed those and then we also sort of kept track of the health of them over the summer."

Create a More Connected Minnesota

MPR News is your trusted resource for the news you need. With your support, MPR News brings accessible, courageous journalism and authentic conversation to everyone - free of paywalls and barriers. Your gift makes a difference.

Director of the lab
University of Minnesota professor Fotis Sotiropoulos is director of the St. Anthony Falls Laboratory.
MPR Photo/Tim Nelson

For the last 69 years, that hasn't been possible. The U's original hydro lab, built in 1938, has a giant steel indoor flume where the water runs, but the seasons never change and the sun never shines there.

"Indoors, you've just got a constant temperature, you got a constant amount of light," Gaffney. says. "Out here, we actually can get growth of attached algea, periphyton. You know we can get macro-invertibrates growing, which are just little bugs that hang out in the bottom of the stream channel, and growing this much vegetation inside is really not practical."

The new lab has some other unique features, as well. It's the only gravity powered hydro lab in the world and it actually belongs to Xcel Energy, which owns the hydropower generating plant right next door. It's also already a landmark, lined by weathered walls built of limestone block.

It has a long history, says researcher Anne Lightbody, who manages the outdoor facility.

Scientist Deborah Huddleston works on an experiment in the St. Anthony Falls lab traditional lab space.
MPR Photo/Tim Nelson

"The outdoor stream lab is located in two abandoned spillways from St. Anthony Falls. The spillways were constructed back in the 1870s, when the apron went in on St. Anthony Falls itself. And then in the 1960s, when the lock and dam went in, right across the way, they were no longer needed for flood control, and they've been lying her, waiting for us, since then."

But the new lab isn't just a handy relic, either.

Researchers hope to reuse the other abandoned spillway someday to simulate a bigger, faster flowing stream. It will let researchers better study some of the key environmental issues we face, like threats to water quality, the changing dynamics of the earth's surface brought by climate change and the long term effects of river management like dams, according to Fotis Sotiropoulos, a University of Minnesota professor and director of the U's hydro lab.

"The statistics of rivers and streams in the U.S. are pretty grim. About 45 percent of the three and a half million miles of river in the U.S. are actually degraded. So some of the effects of this we see, for instance, in the poor water quality that many of the streams and rivers have. We see that in the severe effects of the big floods we had recently in the Midwest. With what we do here, we cannot eliminate the floods, but by understanding how we can intelligently intervene, we can actually soften their effect."

Hydraulic lab
The original University of Minnesota laboratory was built by the Works Progress Administration in 1938.
MPR Photo/Tim Nelson

Researchers at the new $600,000 lab are just finishing their first season of study with their man-made stream, focused mainly on figuring out how it works and what opportunities it can offer to other scientists around the world.

But they're opening up the gates for a public grand opening later today. The lab will be open for tours and a kickoff celebration at 3 p.m, at Third and Main, two blocks from the Stone Arch bridge in Minneapolis.