Macomb Co. removing sediment from sewer pipe near 2016 Fraser sinkhole

A thousand tons of sediment impeding the flow in the Macomb County sewer pipe tied to a 2016 sinkhole has been removed, an official said Tuesday.

Macomb County Public Works Commissioner Candice Miller said another 5,000 tons still have to be taken out.

"Six thousand tons of this in our interceptor reduces the amount of capacity that we have for our sewage flow," she said in a statement. "It has to come out."

Miller said the contractor on a $37 million construction project in Sterling Heights that aims to prevent the Macomb Interceptor Drain from collapsing removed the first 1,000 tons of sediment and started taking out the rest.

Located about 60 feet under 15 Mile Road, the three-mile-long, county-owned drain runs between an electric transmission line corridor on the Sterling Heights-Warren border and Garfield Road on the Clinton Township-Fraser border.

The pipe is about 11 feet in diameter and serves more than 500,000 residents and some 40,000 businesses in 11 communities, transporting sewage into a network that leads to a wastewater treatment plant in Detroit operated by the Great Lakes Water Authority.

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

On Dec. 24, 2016, the sewer line collapsed and caused a massive sinkhole on 15 Mile in Fraser. The collapse resulted in 23 homes being evacuated, three homes being condemned and two of those houses later being demolished. It also sparked a lawsuit against the contractors that caused the collapse.

It took the county about nine months to repair the collapsed sewer and sinkhole. The bill for the repairs totaled about $70 million.

Miller said Monday that the sediment in the drain was found during previous inspections and wasn't a surprise. In some places, the sediment is 24 inches to 36 inches thick, she said. She also said most of the sediment was caused by sand from the 2016 sinkhole getting into the pipe.

To remove the sediment, the contractor uses a bulldozer-like vehicle with a curved blade that travels in the pipe while sewage is held back upstream. It scoops up the debris into a large bucket, which is hoisted above ground with a crane, officials said.

The sediment is then loaded into a dumpster and allowed to dry before it's disposed of at a New Haven landfill.

Don VanSyckel, a Republican Macomb County Commissioner who represents the city of Sterling Heights and a member of the Macomb Interceptor Drain Drainage District board, recently visited the work site to see some of the sediment being removed.

"I’m just so glad to help serve on the MIDD Drain board and help to push this project along because it’s high time it gets done," he said in a statement.

cramirez@detroitnews.com

Twitter: @CharlesERamirez