by BEN MCLEOD
The majority of the Whitewater River’s 560 square-mile watershed lies within Winona County. It is easy to locate a map of Winona County, but it’s more difficult to visualize what parts of the area specifically drain into the Whitewater River. Allison Bender, a Minnesota GreenCorps member who is working at the Whitewater State Park this year, has taken on a project to make that visualization easier. She is in the process of building a scale topographical map of all the land that drains into the river, and she’s building it out of Legos.
A river’s watershed is all of the land that drains into it. It expands along every stream and creek that joins the main channel, and the rain and snow melt from all the farmland, bluffs, forests and towns finds its way into that channel. Road salt, fertilizer, silt and other things that travel into a river’s watershed end up in that body of water. And those rivers flow into larger rivers, which flow into lakes and oceans. To determine from where silt or pollutants are coming and how they end up in the water, it is important to identify the features of the watershed. “I guess I’m hoping that this gets people learning ‘What even is a watershed?’ [I hope people will learn] more about the connections to land use and how we have an impact on water quality in Southeast Minnesota, and how these things are interconnected,” said Bender. “Like Beaver Village.” Beaver was a community initially settled in 1854 in the Whitewater Valley. Beaver grew and thrived, becoming one of the larger towns in the region, until farming along the hillsides stripped the rich topsoil, which combined with the gradually exposed sandstone underneath to crush Beaver under frequent floods. The town itself was bought up by the state in 1932 and razed, and now almost nothing remains on the site to show Beaver ever existed. By neglecting the way the land and water interact, the town appeared to have drowned itself. And it’s not the only community that the Whitewater has wiped out of its valley.
A full map of the drainage area of the Whitewater River made out of Lego bricks will provide a clear, visual display of how watersheds work. Bender explained that the map will be color-coded for land use, “Yellow for crops, green for forests and grey for urban areas.” It’s an ambitious project that will take thousands of bricks, and requires specialized plotting programs. “When we began the process we had a crazy idea that the side of it would display the rock strata,” Bender recalled, “but it was way too complicated.”
Dr. Dylan Blumentritt, assistant professor at the Winona State University Department of Geoscience, said of their ambitious project, “It got complicated really quickly. There is some tilting of the beds. We decided from a design standpoint that would have been a little bit too much.” If the entire project will be completed at six feet by four and a half feet, and each Lego “button” represents about 630 feet, this map will be more complex than an afternoon spent building a toy helicopter or castle. “We did the mapping of the watershed and got grid sizes, and a Lego club out of the Twin Cities essentially took our model with elevation and each cell size,” said Blumentritt. “They have a custom computer program which divided up the map into modules and designed instructions for each module.” This is the same kind of program Lego sculptors use to design and build large statues and landscapes, such as those on display at the Mall of America. “I thought, ‘we’ll just design a model and put it together like the pieces of a puzzle,’” explained Blumentritt, “but that would be way more work than this more coherent plan.” The entire map will be broken up into smaller eight-by-eight sections, and each of those will go onto a larger eight-by-eight inch plate, which will then be assembled with the rest of the plates.
Volunteers assisting in the build will appreciate that, and the project will definitely need volunteers. “It’s all about reaching out to community members and students,” said Bender. “We have some tablets but we recommend people bring phones.” The finished project is expected to be separated into four very large parts which can be transported and reassembled for display. “Wabasha, Olmstead and Winona County Water Conservation districts are partners in the project from early on, and we’re offering them the use [of the map] at booths at county fairs, farmers markets, libraries, and Winona State University will use it in the geosciences department,” Bender said. “One volunteer has connections at the Science Museum, and they have a Lego exhibit of the world’s tallest buildings made out of Legos.”
There is an online signup for Sunday’s giant geological assembly. They want exact numbers since they expect to have refreshments on hand, and plan to order pizza in the afternoon. They know that they’ll need precise measurements for this kind of project.
Interested parties can sign up using the Google form that is linked to the project’s Facebook event. Any questions can be emailed attention to Allison Bender at email@example.com.