FLINT, Mich. — About 22 percent of excavations tied to Flint’s lead-tainted water crisis have led to copper pipes that do not pose a threat of leaching lead, city records show.

Flint Action and Sustainability Team project coordinator Michael McDaniel called the 22 percent a “failure rate” because crews shouldn’t have to spent time excavating areas that aren’t problematic, according to the Flint Journal, which obtained the records (http://bit.ly/2pUhuje ).

“To cut down on the number of times our pipe replacement crews are finding copper pipes, we plan to check the service lines at 4,000 homes with hydro-excavation trucks,” McDaniel said in a written statement. “The trucks use pressurized water to dig two small holes down to the service line to determine its composition, enabling pipe replacement crews to skip homes where copper pipes are found.”

Flint is replacing old water service lines that leached lead into homes and businesses because the city for 18 months did not properly treat the water to reduce corrosion. Lead leaching from old pipes and fixtures caused elevated levels in children and left residents to drink and bathe with bottled or filtered water.

McDaniel said that two companies — M.L. Chartier Excavating and Dependable Sewer Cleaner — have been awarded a sum of $1.2 million in hydro-excavation contracts and will begin work as soon as the Receivership Transition Advisory Board for Flint approves the contracts.

City officials have known since 2015 that there would be issues identifying which of the 55,000 Flint properties have lead or galvanized water service lines, which connect homes to water mains.

The city plans to remove and replace 6,000 service lines this year.

The crisis happened after the city switched to untreated Flint River water as its drinking-water source in a money-saving effort in 2014, while under state management. Flint returned to Detroit’s water system in 2015.


Information from: The Flint Journal, http://www.mlive.com/flint