In the battle against snow and ice that is waged every winter day on Michigan’s roads, salt remains and essential ingredient. MDOT records for 1991 show that 442,223 tons of road salt were applied to 10,000 linear miles of trunk line maintained under MDOT’s jurisdiction. The Wayne County Road Commission notes that a single salt run for a truck can use up to 12 tons of salt, depending upon the truck size. That page has several more bits of trivia including the fact that at temperatures below 20 degrees, salt begins to lose its effectiveness. It becomes almost completely ineffective at 0 degrees or colder.
The Salt Institute’s page on Michigan salt says that estimated salt deposits in Michigan are astronomical. In the Detroit area alone, it is believed that there are over 71 trillion tons of unmined salt. Geological studies estimate that 55 counties of the Lower Peninsula cover 30,000 trillion tons of salt.
Our largest salt mine is actually the Detroit Salt Mine, operated by the Detroit Salt Company (closed for a time but now re-opened, comes with an annoying & loud Flash warning) and I suppose is makes sense that in 1940 Detroit became the first major city to use rock salt for snow and ice control. The Great Lakes Radio Consortium’s Ann Murray has a great report titled Exploring a Great Lakes Salt Mine that takes you inside the Cleveland salt mine that extends under Lake Erie. The best exploration of the mine is via The ghostly salt city beneath Detroit in the Detroit News:
In a 1925 Detroit News article, miner Joel Payton told about his salt mine job. “The only dirty part of this job is going down to work,” Mr. Payton explained.
“I have to wear this old outfit because the big buckets that take us down get smudgy from the action of the sulphur water on the iron of the buckets.
“The mine itself is dry and clean as pure rock salt in a solid vein 35 feet thick is bound to be. The high vaulted rooms that we have hollowed out have sparkling white floors, walls and ceilings.”
Payton continued, “One reason we don’t have any rats in our Detroit mine is because the rats would have nothing to eat except the leavings of our lunch pails. And by the way, not only are there no rats or cockroaches or other living creature in our mine, but also no remains of living things from past ages. The salt vein is, of course, a dried up sea that once covered this section for hundreds of miles. You’d naturally suppose that some fish or vegetation would have been pickled or fossilized in the brine as it hardened. But I’ve never seen a single fossil or sea shell or any remains of that kind”
The photo above was taken at the Verplank salt dock, Muskegon and you can see more photos of otisourcat has taken of Michigan road salt.