Joining Efforts to Restore a Sacred Gathering Place

Many of the unique land formations in what is now called the Twin Cities Metropolitan Area are sacred to indigenous peoples.

 This is true of a special place along a bend in the Mississippi River in downtown St Paul, where a series of springs flow from caves tucked into the sandstone bluffs. This place, named Wakáŋ Tipi by the Dakota, has been a sacred gathering site for thousands of years, with burial mounds at the top of the bluff. But now, this place is highly affected by urban development. Nearby streams that used to flow into the river move through underground pipes, I-94 winds its way along one edge, with railroad tracks buffering the other, and scars of past industry and railyards checker the space, while the caves bear damage from vandalism and dynamite.

The “toxins team” of the LTER first came across Wakáŋ Tipi, also known as Bruce Vento Nature Sanctuary, while staring at maps and spreadsheets. We were looking for places where we could study how urban toxins move through ecosystems, why some species are more tolerant of such toxins, and how ecological restoration might help us deal with these pollutants. As we aligned the Department of Health’s map of childhood blood lead levels with maps of parks and gardens, we noticed that Wakáŋ Tipi falls in an area with some of the highest childhood lead levels in the state. The site was on our radar, and then a winding chain of email forwards put us in touch with the staff of the native-led Lower Phalen Creek Project (LPCP).

It was a warm day in July when we first met up with the LPCP team – Sam, Keeli and Mishaila –  at Wakáŋ Tipi. We criss-crossed the prairie restoration in the site, noting how so many of the plants valuable to pollinators are also important medicinal plants to Dakota people. Cold water trickled out of the gated-off caves, and we gazed up at an amphitheater of sandstone cliffs, tarnished in places by graffiti. As we wandered through the site, we discussed the ways that soil and plant sampling for metals might give a better idea of patterns of remnant and current contamination, converging on questions and approaches that worked for all of us.

A few weeks later, with the permission of LPCP, the LTER team came back with soil corers and paper bags to take samples of soil, and leaves of five species of prairie plants as a first exploration of where metal contamination might be elevated. It was even warmer that day and we had to wear gloves to keep sweat from contaminating the samples, since we were also measuring sodium levels. We dried the samples and sent them off to the analytical lab at the University of Minnesota campus to measure metals. When the data came back weeks later, we all joined together on a Zoom call to do some data analyses. We compared the plants to the same species collected along roadsides to get an idea of what we might expect for a semi-polluted site. It was easy to see that levels of some metals were elevated in prairie plants at Wakáŋ Tipi, like lead and arsenic, but others, like nickel, were not. The soil data were quite patchy, with a handful of subsites showing elevated arsenic, and one area containing somewhat concerning levels of lead. The analysis gave some ideas of what metals might be of concern, but it wasn’t all bad news, as it also highlighted how the plant contamination was likely lower than levels that would kill pollinators at the site.

Some of the soil and plant analyses raised questions about how water might be moving through the site, redistributing toxins from one place to another. It doesn’t take much to get scientists intrigued, and discussing some of the patterns with LTER members who work on aquatic systems has led to a growing LTER-LPCP partnership. We found ourselves touring the site again recently, this time in subzero temperatures, using water probes to take initial measurements of spring-fed water moving through Wakan Tipi through a stream and series of ponds, before entering a final pipe out to the Mississippi River. This spring, a class from St. Thomas University is incorporating many of the water research questions into their own class project, further expanding our growing partnership.

Most rewarding about the research has been how many of the more specific research questions have arisen organically out of collaborative, iterative discussions with LPCP staff. Our findings are informing not only our broader research questions, but also concerns of LPCP and surrounding communities about the overall ecological health of the site. In the longer run, we hope that specific restoration techniques or soil amendments can help to reduce the negative effects of these contaminants. And in doing so, continue to heal this sacred site that has been so tarnished by decades of industrial development, so that it can be a gathering place that also heals its community. While we came into this site through a map of contamination, our connection to this site has grown as we have learned Dakota stories and gotten to know some of the people that value this place so deeply.