A system of tunnels that at one time provided the the Pillsbury "A" Mill with all the power it needed, thanks to the Mississippi River's 50-foot drop at nearby St. Anthony Falls, may soon serve as an energy center once again.
A Minnesota Historical and Cultural Heritage grant is paying for a new study to determine if the tunnels below what was once the world's biggest flour mill can once again harness hydropower in one form or another, or perhaps be a staging area for tapping into the earth's moderating temperatures for geothermal heating and cooling.
Energy created would be used not only for the 1881 "A" Mill once it is redeveloped, but for a
massive proposed complex of new and renovated buildings across a three-block stretch of the Minneapolis riverfront.
The tunnels were part of the greatest direct-drive waterpower complex ever built but fell into disuse with the advent of hydroelectric power generation and the slow exodus of grain milling to cities such as Buffalo, N.Y.
"Given their age, they are in remarkably good condition," says Kathryn Klatt of development firm
Schafer Richardson. The tunnels, or millraces, brought water from above the falls into the "A" Mill via headraces, let it fall down vertical tunnels called drop shafts, then delivered it back to the river by way of two tailraces. Those enormous openings can still be seen at the base of the riverbank in Father Hennepin Bluffs Park.
The $7,000 scoping study for the tunnels complements a $30,000 separate study into the feasibility of engineering for such a project that's already underway.
Source: Kathryn Klatt, Schafer Richardson
Writer: Chris Steller