EAST LYME, Conn. (WTNH) — East Lyme is warning residents who are on low-sodium diets after road salt caused sodium levels in water to jump.

Residents are warned when the levels reach 28 milligrams per liter. The public wells are at more than 40 milligrams per liter.

The criteria for private wells is 100 milligrams.

The town is requiring new developments in aquifer protection areas to use sodium alternatives. Public works crews are also being trained on how to pre-treat roads more effectively.

That includes the proper techniques of how to put the right amount of salt on streets, according to Ben North, a utilities engineer.

“They calibrate it to the lane mile to make sure they’re not over-salting,” North said. “They’re trying to be economical, as well.”

One well with elevated levels is near two schools and a community center.