There are thousands of lead water pipes in St. Joseph County, but local officials say residents have no reason to be concerned about local water quality.

In South Bend, 59 percent of the city’s 41,000 water service lines are lead, while about 25 percent of the 18,359 water service lines in Mishawaka are lead, the South Bend Tribune reported.

The ground water source in South Bend is “hard” and has minerals that leave a thin coating on pipes to keep lead and copper from leaching into the water, Eric Horvath, director of Public Works, told the Tribune. Because of this, the city hasn’t exceeded the maximum allowance of lead in the water supply since testing began in 1992.

South Bend plans to test the water at 200 sites — more than the 50 required by the EPA — later this year.

Mishawaka also has naturally hard water, but the city also adds minerals to the water to prevent lead leaching, Dave Majewski, manager of the Water Division, told the Tribune. The city of Flint, Mich., did not add those minerals to its water when it switched water sources in 2014, leading to the Flint water crisis.

Mishawaka is scheduled to test its water in 2017.

Read more about local lead pipes, including who is responsible for replacing lead pipes, in the story from the South Bend Tribune.