LEWISTON – A new water treatment process, adding ammonia to Lewiston’s chlorinated water, is scheduled to start today.

City crews will begin adding ammonia gas to the city lines at 8 a.m. They’ll flush waterlines throughout the city. Water treated with the new process could take 24 hours to reach individual homes.

The ammonia will bond with chlorine already in the water to create a chloramine compound, a longer-lasting disinfectant.

The new process will help the city meet Environmental Protection Agency guidelines. Chlorine creates byproduct chemicals, and those byproducts are regulated by the EPA. Stricter federal rules are forcing the city to reduce those byproducts.

The city was scheduled to begin the process last week, but delayed it until temperatures climbed above freezing daily on a regular basis.

Auburn began treating its water with ammonia last year. Nine other Maine cities, including Portland and Bangor, use the same process.

– Scott Taylor