Keith Matheny

Detroit Free Press

James Heath stood inside a bigger than 12-foot diameter sewer line, more than 50 feet below the ground in Edison Corridor south of 15 Mile Road in Sterling Heights. And he was scared.

It was December 1979, and a Detroit Water and Sewerage Department crew had discovered a crack about two miles upstream on the 15 Mile Interceptor, a major east-west sewer line that dumps into the Edison Corridor line. Heath had helped put the pipes into service with much fanfare just seven years before, in July 1972, as rapidly expanding Macomb and Oakland counties were connected to Detroit's vast wastewater treatment system.

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Near the 15 Mile Interceptor crack, a large area of silt and sand around the pipeline was gone. Heath was part of the crew walking inside the huge Edison Corridor pipeline, attempting to determine where the sand had ended up. About 400 feet into the Edison Corridor line from its juncture with the 15 Mile pipe, they found it.

There, the Edison Corridor pipeline had sunk more than 6 feet, causing cracking all around it. "It looked like somebody had taken dynamite and set it off," Heath said.

The sand and debris within the pipe at that depression site were so deep that Heath, standing 5 feet, 10 inches, could stand on the pile and touch the top of the 12-foot, 6-inch pipe. Nearby, a huge chunk of the top of the interceptor line — 15 feet long, 5 feet at its widest point and 16 inches thick — had collapsed inside. Only 55 feet of weeping, wet earth lay between them and the surface.

Heath expected the ground and pipe to come crashing down on them at any second. "I thought, 'I'm going to die in (expletive) water,'" he said. "It took me 20 minutes to retain my composure."

A nearly 40-year veteran of the Detroit Water and Sewerage Department before retiring in 2002, Heath said he believes the sinkholes that keep plaguing the 15 Mile line — including the Christmas Eve sinkhole in Fraser that has one house sinking, with 22 other residences indefinitely evacuated, and will close 15 Mile Road for months — involve a failure to reinforce some of the pipes, faulty connections into them and a lack of frequent-enough inspections.

"I don't think it's any one person," he told the Free Press. "It's a systemic problem with communities that fail to perform inspections like they should."

The Edison Corridor pipeline hadn't been inspected in the seven years after it had been installed, prior to the late 1979 collapse, Heath said. Following the pipe collapse, and a subsequent review by the U.S. Army Corps of Engineers, Heath said he committed to inspecting the line at least twice per year. "And we did that," he said.

"Inspection and maintenance should be a continuous process," Heath said. "I think there was a lax period where the inspection was not being done as often as it should."

Heath retired as the Detroit Water and Sewerage Department's assistant director of water operations in 2002, two years before the August 2004 sinkhole near 15 Mile and Utica roads in Sterling Heights that again closed 15 Mile for months and cost $53 million to repair. That incident helped prompt the transfer of the sewer system in 2009 from Detroit to Oakland and Macomb counties and a jointly created entity between the two counties, to facilitate undertaking more than $170 million in multi-year infrastructure improvements to the system.

Outgoing Macomb County Public Works Commissioner Anthony Marrocco, who was defeated by former Congresswoman Candice Miller in the Nov. 9 election, has not responded to Free Press messages seeking comment. Macomb County construction engineer Tom Stockel told the Free Press late last month that the section of the 15 Mile Interceptor near the collapse was last inspected in 2009. Minor cracking was found and grouted the following year, he said. "At that time, it was minor repairs. Everything was fine."

But given the intensely stepped-up pipeline inspection regiment on the Edison Corridor Interceptor following its 1979 collapse, Heath questioned why more diligence wasn't paid to an area so close to the 2004 sinkhole location, noting the last inspection was seven years before this Christmas Eve's sinkhole.

"I would say somebody was falling asleep," Heath said. "Out of sight, out of mind — that's the mentality of too many bureaucratic people running systems."

Stockel did not return messages Friday, but earlier said, "Our pipes will be inspected, and they are inspected on a regular basis."

Following the 1979 collapse of the 15 Mile Interceptor and resulting sinkhole, Jenny Engineering conducted an investigation of the incident on behalf of the City of Detroit, and recommended inspections of the pipeline every year until no changes were observed; then inspections no less frequently than every three years.

One of the issues in the Macomb area is the different soil composition, Heath said.

"Detroit's area for sewers are in more what they call Detroit clay," he said. "Up above 8 Mile Road, the elevation goes higher and higher, and the clay beds remain at kind of the same level. So a lot of that work is done in sand and water."

Many of the pipes in the area were not reinforced with steel bar, but probably should be, Heath said. Ground stabilization through grouting and other steps also is appropriate.

A continuing reduction in workforce, under the Detroit Water and Sewerage Department and now the regional Great Lakes Water Authority, doesn't help, Heath said.

"To have 3,000 miles of sewers and all of the systems in seven counties, to have five water treatment plants and the wastewater treatment plant, to say you can run that entire system with about 300 people, you've got to be damn loony," he said.

Contact Keith Matheny: 313-222-5021 or kmatheny@freepress.com. Follow him on Twitter @keithmatheny.