Springs are an essential part of the St. Croix. Throughout the watershed, they gush or seep out of the ground, down the banks, and into the river.
In this short video, spring expert Greg Brick shares a little about the bubbling streams that people and wildlife have been using for millennia. Before we drilled wells deep underground and installed water systems in cities, springs were the freshest sources of water around. They continue to support plants and animals not found elsewhere along the bluffs.
Brick says there are hundreds of known springs along the length of the St. Croix. They are unique features and critical to the river’s health.
The same water that feels so cold in summer is the warmest thing around in the winter. When the air hits zero degrees and the river is locked in ice, the spring water continues to flow, often keeping open a small pocket of water along the shore. In areas with lots of springs, it can create enough open water to host trumpeter swans and other birds that stay all winter.
All springs are sublime places, the sound of water flowing over rock fills one’s ears. The water is always a foot-freezing 40 degrees Fahrenheit. They are usually lush and green, with even watercress and other plants growing in the water while the surrounding landscape may be covered in snow.
But not all springs are the same. In the video, Brick explains that the St. Croix has essentially two types of springs: bedrock and loose glacial material.
Putting springs on the map
Brick was standing by one of the bedrock springs common to the lower St. Croix, on a steep slope below the Soo Line High Bridge north of Stillwater. He had scrambled up the bluff to find the source of a rushing rill. There, he used a tablet computer and a variety of probes to measure the water quality, and upload it to the DNR’s database.
Brick has been mapping springs since he was an undergraduate student at the University of Minnesota, while pursuing a degree in geology. He conducted the first systematic project to map springs in the Minneapolis-St. Paul area, and has also conducted extensive explorations of caves and other subterranean spaces in Twin Cities and across the Midwest. Brick has published books including Subterranean Twin Cities, Iowa Underground: A Guide to the State’s Subterranean Treasures, and his most recent, Minnesota Caves: History & Lore.
The video was filmed while Brick was working for the Minnesota Department of Natural Resources mapping springs across the state. The two-year project set out to create a database that included as many springs as possible. It included a citizen science project, with a web form which let the public contribute, and digitizing old records. And it involved Brick venturing across the state, trekking miles through trackless woods, to put Minnesota’s springs on the map.
“We can’t protect what we don’t know is there,” Brick said.
The spring survey was funded by the Minnesota Environment and Natural Resources Trust Fund (provided by the state lottery), as recommended by the Legislative-Citizen Commission on Minnesota Resources.
The inventory was cut six months short, ending in December rather than this coming June, due to the state legislature “raiding” the fund last year to pay for unrelated infrastructure projects in the final hours of negotiations over the state budget. Environmental groups are now suing to reverse the raid.
The Minnesota Spring Inventory Database is available to explore here.