Tim Gentile, of Northeast Earth Mechanics, right, takes a hammer from his supervisor Mike Kelley to knock out a section of water main while cutting the line to install a new valve on Poverty Lane in Lebanon on Monday.

The work is part of the installation of an isolation valve at the site, designed by city engineer Rod Finley, to improve water quality in West Lebanon along Route 12A by balancing water from two of the city’s water storage tanks and replenishing the Farnum Hill tank’s reserve daily. Finley expects the project to be complete by early October.