Plans to double the size of a Wal Mart in Hermantown, near Duluth, Minnesota, have drawn the community’s attention to a small trout stream near the site. In February a coalition of community groups succeeded in bringing the debate to center squarely on their city council’s need to protect Miller Creek by insisting on an environmental impact statement or EIS.
The parking-lot runoff problem is not new to Hermantown, a suburban Duluth area that already sports dozens of sprawling, mall-style developments, each equipped with acres of impervious roofs and parking lots.
Regionally, pavement is a big and growing problem for Western Lake Superior. Since August of 2003,Wal Mart alone has either opened, started building or announced plans for four new “Supercenters”, construction of which will add more than 40 acres of additional impervious roof and pavement, all within less than an hour of the Hermantown,Minnesota location.
The Miller Creek location where Wal Mart is looking to expand is within the most densely paved area in its watershed. Even without the bigger store’s added pavement, wetland destruction, salt, sediment and water temperatures too warm for the brook trout have gotten Miller Creek listed on Minnesota’s “impaired,” waters list. Researchers mapping the watershed have measured the percentage of impervious surface in the area of the watershed near the malls at 22%.
Neighbors, retailers and unions joined forces under the name “Good Neighbors for Responsible Growth” to insist on the most careful scrutiny for past practices and the best practices in the future. Debbie Ortman is one of the leaders in Good Neighbors for Responsible Growth. As a member of a special task force for Miller Creek, Ortman was all too familiar with problems caused by runoff from large paved surfaces. Good Neighbors’ research revealed thatWal Mart had failed to report on the performance of its stormwater retention pond, a revelation that gained substantial interest from local news media when the group brought it to the attention of the city council.
Ortman says the council showed interest in the information. “We were able to raise questions about the company’s willingness to work to protect the sensitive environment at the site,” says Ortman, adding; “concerned citizens packed into a standing-room-only crowd at a city council meeting made good video for the news.”
But technical questions arose. How much pavement could a watershed take before it sheds water too hot, muddy, full of crud for the fish? That question, along with educating the community on solutions occupies Minnesota Sea Grant’s Jesse Schomberg. Schomberg and his team have put together an interactive web site that shows what happens to Miller Creek and other Duluth streams under a range of development scenarios. At 5% more impervious surface—an increase to 27% impervious—the entire portion of the creek downstream from the concentration of pavement where the Wal Mart expansion is proposed, turns dark brown,signifying unacceptably high levels of salt, solids and temperatures too high for the native trout.
Schomberg says that development in the Miller Creek watershed has been a problem for the brook trout for some time.“There are sections where they’re [the trout] just gone,” says Schomberg.
As to how much more pavement it will take to completely ruin the creek, the educator is insistent that won’t be known until it’s too late to take preventive action. “You can’t find that one foot that crosses the line from cold and clear to warm and muddy,” says Schomberg about the volumes of research data researchers have amassed on Miller Creek. “Each piece of pavement adds to the problem and the bigger the piece, the bigger the problem,”adds Schomberg.The actual percentage of pavement added by the Wal Mart expansion will be far less than 1%.
Fueled by media reports about less than responsible past practices that seemed to raise serious questions about how the company would behave in the future, the “Good Neighbors” group faced off with the city council mid-February for a vote on whether or not to ask for an EIS. Once again the council chambers were packed. Experts were there to testify that the environmental analysis in the environmental assessment worksheet or EAW was inadequate to predict what would happen to Miller Creek. The City Council voted 4-1 to accept the EAW and proceed with the construction.