The Dow Chemical Company facility in Midland, Michigan, began operating in 1897. The 1,900-acre facility abuts the Tittabawassee River; most of the plant is located on the east side of the river and south of the city of Midland. At various times, the Midland Plant produced over 1,000 different organic and inorganic chemicals. Dioxins and furans were byproducts formed during the manufacture of chlorine-based products, starting in the early 1900s. Elevated dioxin levels in and along the Tittabawassee River and downstream appear to be primarily attributable to particles in liquid wastes that were discharged in the past directly into the river from the facility.
Past waste disposal practices at the Midland Plant have resulted in on and off-site contamination that settled in some sediment and built up in some riverbanks and floodplain areas. Off-site contamination extends over 50 miles downstream through the Tittabawassee and Saginaw Rivers and into Saginaw Bay.