(CNN) -- Michigan Gov. Jennifer Granholm is calling on the Environmental Protection Agency and a Canada-based energy company to step up efforts to contain an oil spill in the Kalamazoo River, after more than 840,000 gallons of oil leaked from a pipeline since Monday.
"There needs to be a lot more done," the governor said Tuesday, after touring the river area in a helicopter. "We don't have enough resources right now for containing the spill to the level where we can feel comfortable."
"The last thing any of us want is to see a smaller version of what has happened in the Gulf," she said, referring to the BP oil spill in the Gulf of Mexico.
Oil began leaking from the 30-inch line Monday, moving from Talmadge Creek into the Kalamazoo River, which flows from near the city of Battle Creek into Lake Michigan. The pipeline normally carries 190,000 barrels of oil per day from Griffith, Indiana, to Sarnia, Ontario.
Officials do not know what caused the oil to leak, but the pipeline now has been shut down. It is owned by Enbridge Energy Partners, based in Canada.
The slick spans some 16 miles, and the governor is worried it could reach popular Morrow Lake, between Battle Creek and the city of Kalamazoo.
Crews staffed by Enbridge are using booms to try to contain the oil and vacuum trucks to clean it up. The effort is being supervised by the EPA.
But Granholm fears the slick may spreading faster than it can be contained.
"Clearly this is a significant incident," she said. "It cannot be taken lightly. We need all hands on deck."
The river right now is close to flood stage, complicating efforts to contain the slick.
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Two homes near the spill site have been evacuated, and 25 people worried about health issues have been relocated, according to Jim Rutherford, health officer with the Calhoun County Health Department.
Officials say there's no immediate danger to drinking water.
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Wildlife has been affected, with some fish and birds coated in oil. The energy company is preparing a wildlife rehabilitation center for treating the animals.
People are being urged to avoid swimming or fishing near the affected areas.
CNN's Scott Thompson contributed to this report.