New Jersey Natural Gas wants to spend more than $200 million to upgrade portions of its aging infrastructrure, according to a release from the Wall-based company.

NJNG on Tuesday asked the Board of Public Utilities to approve the $204 million, five-year project that seeks to replace 343 miles of aging, cast-iron and unprotected steel piping within its infrastructure in Monmouth, Ocean and Middlesex counties, the release says. The company has about 7,000 miles of distribution piping.

The aged pipes were state-of-the-art in the 1970s but account for 95 percent of all leaks found in the utility’s system, the release says.

Pending approval, NJNG will seek a rate increase amounting to about $8.44 on customers’ average annual bill over the life of the program, which the company is calling the Safety Acceleration and Facility Enhancement (SAFE) program, according to the release.

“Ensuring safe, reliable service for our customers and the communities we serve is the most important thing we do” Laurence M. Downes, the gas company’s chairman and CEO, said in the release.