A change in disinfection methods for Illinois American Water may have some customers confused by a stronger taste or odor of chlorine in their drinking water.

The company is adjusting its treatment process from May 19 through June 16, according to a statement released Tuesday afternoon.

“Free chlorine,” which is free of ammonia, is an alternate form of the chemical and has been switched in to prepare for a major water main flushing program scheduled to begin around Memorial Day.

The program is designed to flush mineral deposits and sediment from water mains. Major portions of the work are scheduled to occur overnight but are not expected to interrupt service to any customers.

There is a possibility residents may experience lower water pressure or discoloration if crews are working nearby. If this occurs, the company recommends letting the water run clear before using it and not doing laundry while crews work.

Customers with persistent problems can contact the company at (217) 352-1420.