The governor declared a state of disaster in Calhoun County and affected areas along the Kalamazoo River, the Battle Creek (Mich.) Enquirer reported Wednesday.
Crude oil flowed into a creek leading to the river in western Michigan following a malfunction Monday in an underground pipeline owned by Enbridge Inc., the newspaper said.
Pipeline pumps were shut down once the leak was detected but not before some 800,000 of gallons of oil spilled.
Booms were set up Tuesday morning in four locations along the Kalamazoo River, and about 200 people, 21 boats, 8 miles of boom and 30 oil-siphoning trucks were on the scene, Enbridge Executive Vice President Steve Wuori said.
Visiting the site of the spill late Tuesday, Granholm was critical of the company's efforts.
"There needs to be a lot more done," she said. "There are not enough resources right now on the river to contain the spill to the level we'd like to see."
Calhoun County Sheriff Al Byam said the timing of the spill is especially bad because recent storms have widened the river and caused it to carry the oil more quickly.