 Calhoun County comprises the Battle Creek, MI Metropolitan Statistical Area and is included in the Kalamazoo-Battle Creek-Portage, MI Combined Statistical Area.According to the U.S. Census Bureau, the county has a total area of , of which is land and (1.7%) is water.The Kalamazoo River oil spill occurred in July 2010 when a pipeline operated by Enbridge (Line 6B) burst and flowed into Talmadge Creek, a tributary of the Kalamazoo River.