The existence of rock salt in the Detroit area was discovered in 1895. By 1906, the Detroit Salt and Manufacturing Company was ready to tackle the chore of creating a local rock salt mine. The struggle down to the salt beds is one of the most impressive engineering accomplishments of its time.
From the sinking of the first shaft, construction crews were faced with daunting challenges. Hydrogen sulfide gas and hundreds of feet of stone and glacial drift proved to be large impediments to their progress. Sinking the shaft also was a costly undertaking, causing the Detroit Salt and Manufacturing Company to go bankrupt before ever reaching the prize of its efforts - salt.
Following a business reorganization, the new Detroit Salt Company completed the 1,060-foot shaft in 1910. Just two years later, the mine changed hands again following an acquisition by the Watkins Salt Company, which incorporated the new organization under the name Detroit Rock Salt Company. After sinking the shaft another 100 feet, miners began working a second salt bed. The new operation improved productivity and delivered higher purity rock salt. The success of the Detroit mine quickly caught the attention of a competitor, the International Salt Company. Strategizing to maintain its hold on the Midwestern market, International Salt purchased the mine.
By 1914, the Detroit mine was producing 8,000 tons of rock salt each month, mainly for the leather and food processing industries. An increase in manpower, money and equipment was paying off in a big way. Workers turned electric locomotives, mechanical shovels and electric power to help alleviate the physical demands of mining. These advancements in technology pushed the Detroit mine to even greater productivity.