The Kalamazoo River oil spill occurred in July 2010 when a pipeline operated by Enbridge burst and flowed into Talmadge Creek, a tributary of the Kalamazoo River near Marshall, Michigan. A 6-foot (1.8 m) break in the pipeline resulted in one of the largest inland oil spills in U.S. history. The pipeline carries diluted bitumen (dilbit), a heavy crude oil from Canada's Athabasca oil sands to the United States. Cleanup took five years. Following the spill, the volatile hydrocarbon diluents evaporated, leaving the heavier bitumen to sink in the water column. Thirty-five miles (56 km) of the Kalamazoo River were closed for clean-up until June 2012, when portions of the river were re-opened. On March 14, 2013, the Environmental Protection Agency (EPA) ordered Enbridge to return to dredge portions of the river to remove submerged oil and oil-contaminated sediment.

Enbridge Inc. is a Canadian multinational pipeline and energy company headquartered in Calgary, Alberta, Canada. Enbridge owns and operates pipelines throughout Canada and the United States, transporting crude oil, natural gas, and natural gas liquids, and also generates renewable energy. Enbridge's pipeline system is the longest in North America and the largest oil export pipeline network in the world. Its crude oil system consists of 28,661 kilometres of pipelines. Its 38,300 kilometre natural gas pipeline system connects multiple Canadian provinces, several US states, and the Gulf of Mexico. The company was formed by Imperial Oil in 1949 as the Interprovincial Pipe Line Company Limited to transport Alberta oil to refineries. Over time, it has grown through acquisition of other existing pipeline companies and the expansion of their projects.