What Lies Beneath

As the metro Detroit area grew, a new Lake Huron water intake and treatment plant was built to serve both the Detroit and Flint areas. In 1968, the Detroit Metro Water Department began a $125 million project to dig a water intake tunnel through the bedrock beneath Lake Huron and to construct a large treatment facility for raw lake water. Completed in 1973, the system included a submerged intake crib five miles from shore connected to a 16-feet-wide, six-mile intake tunnel under the lake. The tunnel, 230 feet below this location, connected to a filtration plant one mile west. Four pumps with a daily capacity of 600 million gallons lifted the raw water 53 feet so it could flow by gravity through treatment, after which it was distributed across a 1,079-square mile service area serving more than 126 communities. A boring machine cut through the bedrock beneath the lake at a rate of 150 feet a day, and by the end of the project an estimated one billion pounds of rock had been removed. During construction, a massive explosion ripped through the tunnel and killed 22 workers. On August 21, 2007, thirty-six years after the tragedy, a memorial was dedicated to honor those killed in December 1971 and to remember that they lost their lives so others would have safe drinking water.

Michigan · United States