LEWISTON – Cold weather will delay a new treatment technique for city water for at least a week.

The city will wait to begin adding ammonia to Lewiston’s water supply. The ammonia will bond with chlorine already in the water to create a chloramine compound, a longer lasting disinfectant.

“We cannot start adding chloramines because if we flush hydrants in the city like we need to, we will create icy road conditions and dangerous driving conditions for the public,” said Kevin Gagne, deputy public services director.

The city will wait until temperatures are above freezing daily on a regular basis. The new process is tentatively scheduled to begin on March 7, weather permitting.

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 reduction of those byproducts.

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