Rock salt stops working below roughly 15 degrees, which Bismarck sees for weeks at a stretch. We switch to liquid pre-treatments and heavy-grit traction sand so surfaces stay usable through sub-zero temperatures and freeze-thaw cycles.Rock salt stops working below roughly 15 degrees, which Bismarck sees for weeks at a stretch. We switch to liquid pre-treatments and heavy-grit traction sand so surfaces stay usable through sub-zero temperatures and freeze-thaw cycles.






