MACOMB COUNTY

County may issue bond to fix Fraser sinkhole

Charles E. Ramirez
The Detroit News

Clinton Township — Macomb County may seek a bond issue and a rate hike to pay to repair damage caused by the sinkhole on 15 Mile in Fraser, County Public Works Commissioner Candice Miller said Wednesday.

“I think both those of those things are very likely,” Miller said during a news conference on Wednesday in the lobby of her offices in Clinton Township.

Miller offered no specifics, such as how much the repair would cost or how large the rate hike would be for residents.

Four days into office, Miller called the conference to provide an update on the progress being made to fix the sinkhole problem which has displaced the occupants of 22 homes, three of which have been condemned.

Miller said work to build a temporary bypass of the ruptured sewer line continues and it will take three to four weeks to complete.

She said the sinkhole is about 300 feet-long and crews have built pillars of grout to stabilize the soil around the sewer line. Miller said crews are trying to avoid pumping raw sewage into the nearby Clinton River and prevent it from backing up into nearby homes.

“However, it’s still a possibility,” she said and asked homeowners served by the sewer line to continue water conservation efforts.

Miller said she and Macomb County Executive Mark Hackel were in a conference call with Michigan Gov. Rick Snyder Wednesday morning.

“He’s very interested in what’s going on with the Fraser sinkhole,” she said. “There may be potential for an emergency declaration. It could be announced and we’re at looking at that. We need to see if there are other possible sources of funding. We are exploring every avenue.”

Snyder wants to take a tour of the sinkhole site, Miller said.

In addition, the former Republican Congresswoman confirmed the three homes closest to the Fraser sinkhole have been condemned.

Plans to allow the other 19 homeowners in the subdivision to return to their homes by Jan. 9 are still on track, Miller said. A temporary road has been built for them and natural gas service has been restored. She said water to the homes has been tested, but will be tested again.

Hackel said the county is exploring the possibility of purchasing the homes from their owners.

Miller, who unseated former public works commissioner Anthony J. Marrocco in November, laid out a theory of why the sewer line failed.

Miller explained that after a sinkhole emerged along the sewer in 1979, a contractor working on the repair project drilled more than 10 holes, each about 2-inches in diameter, into it to enable crews to conduct an inspection. A chemical grout was used to fill the holes once the process was completed.

Jason Edberg, vice president and principal engineer for NTH Consultants LTD, said at Miller’s news conference that the holes were bored into the bottom of the sewer line and are not visible because there’s always about 3 feet of sewer water on top of them.

“It would never be visible to the human eye or a camera,” Edberg said. “It could go undetected for decades.”

He said it’s possible groundwater around the pipe has been entering it through those holes and eroding away the soil around the sewer line.

NTH Consultants worked on the 2004 sinkhole on the sewer line on 15 Mile in Sterling Heights, which was about 1/3 of a mile from the one in Fraser.

“At this point, it’s just a theory,” Miller said.

Officials said the 100-foot-wide, 300-foot-long sinkhole that appeared Dec. 24 was caused by the collapse of the leaking Macomb Interceptor Drain sewer that runs under 15 Mile, the border between Clinton Township and Fraser.

The county-owned Macomb Interceptor transports sewage from 11 northern Macomb County communities into a network that leads to a wastewater treatment plant in Detroit operated by the Great Lakes Water Authority.

A 3-mile-long, concrete sewer main, the Macomb Interceptor runs west along 15 Mile from Garfield to ITC Michigan’s electric transmission lines corridor. The pipe is about 11 feet in diameter.

At the ITC corridor, the line connects to a giant sewer transmission line, the Oakland-Macomb Interceptor, which serves 850,000 residents in 25 municipalities in Macomb and Oakland counties.

The two counties purchased the sewer line from the city of Detroit in 2009.

At the time of the 2004 sinkhole, the Macomb Interceptor was owned by the Detroit Water and Sewerage Department.

Its collapse created a sinkhole that took months and tens of millions of dollars to fix.

It was also at the heart of a 2011 lawsuit touching on the corruption scandal of former Detroit Mayor Kwame Kilpatrick.

cramirez@detroitnews.com