FRASER (WWJ/AP) – The sewer pipe is now completely blocked at the big Fraser sinkhole — and the push is on to prevent any backups that would force officials to pump raw sewage into the Clinton River to avoid overflow into basements.

About 400,000 people in 11 Macomb County communities on Thursday were asked to take shorter showers, only flush solids and wash only full loads of clothing as part of a voluntary water conservation plea until a fix for the damaged sewer interceptor line along 15 Mile Road is complete.

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Additional instructions Friday included using paper plates and reusing towels.

Included are Fraser, Sterling Heights, Utica and New Haven and Chesterfield, Shelby, Clinton Township, Harrison, Lenox, Washington, and Macomb Township, plus Selfridge Air National Guard Base.

The cost to fix a broken sewer line that caused a football field-sized sinkhole north of Detroit is estimated at more than $78 million, Candice Miller, Macomb County’s new public works chief says.

The sewer collapse was discovered after Fraser homeowners heard noises Christmas Eve and noticed their house was sinking.

Miller said neighboring Mount Clemens has just stepped up with help.

“…We’re taking immediate action to be able to divert a bit of our (sewage) flow into the Mount Clemens system,” she said. “So, you know, I won’t go through all the mechanics of that, but eventually we’ll be able to divert a bit of our flow to Mount Clemens.”

Still, she said, they can’t take any more rain.

Officials have not yet determined exactly what caused the sewer collapse, but said earlier this month that a 2-inch diameter hole bored through the pipe after a 1978 collapse may have allowed groundwater to move up into the line and erode the soil beneath the pipe.

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Miller told Macomb County commissioners on Friday the project’s cost could rise above $100 million if more work is done to improve the rest of the sewer line. The repairs could take about a year to complete.

An immediate fix to remediate the pipe issue is expected to take about at least a month.

“This is an enormous thing that’s happening to the county,” Miller said. “We’re up to the challenge. We’re going to get through this thing. We’re going to solve this problem. And somehow we’ve got to figure out how to pay for it.”

Officials temporarily evacuated nearly two dozen homes at Christmas time because water and gas service had to be shut off. Nineteen families have since been allowed to return. Three homes were eventually condemned.

Gov. Rick Snyder declared a state of emergency, allowing state resources to be funneled to Macomb County. That could also lead to seeking money from the federal government.

Miller said the county may use bonds to help pay for the repairs.

“We’re starting to talk about what we have to do from a financial standpoint here,” Miller said. “We’re probably going to do a short-term bond. Maybe a long-term bond because we need some immediate cash for many of the expenses here.”

Water and sewage rates may also increase.

“The numbers are a little bit staggering, but at the same time, we are not sure yet where we’re going to end up, or how much money we might be able to offset by with some funds the federal and state government,” said Bob Smith, county commission chair.

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