The O’Fallon Water Division serves all areas within O’Fallon and Fairview Heights city limits and portions of the unincorporated area outside both communities.
The system serves a population base of nearly 40,000 through approximately 16,000 service delivery points.
The system presently uses an average of 4.0 million gallons of water per day (mgd) with peak usage approximately 8.0 mgd.
Raw water from the Mississippi River is processed and treated for consumption by the Illinois American Water Co. at their East St. Louis water treatment facility.
Potable (drinkable) water is purchased wholesale from the Illinois American Water Co. and delivered to customers through a pipeline distribution system owned and maintained by the O’Fallon Water Division.
The water distribution system is comprised of approximately 180 miles of water mains, two pumping stations, three 500,000 gallon elevated storage tanks, two 1,000,000 gallon elevated storage tanks, one 500,000 gallon ground-level storage tank and one 1,000,000 gallon ground-level storage tank.
The O'Fallon Water System uses an Automated Meter Reading (AMR) system to provide change from quarterly billing to monthly billing. Water meters have small radio sending units that provide accurate readings directly to computer operated billing equipment.
A Geographic Information System (GIS) assists in records management and information retrieval.
Extensive water testing is regularly done to assure safe drinking water.
Illinois American Water Co. conducts more than 30 tests for water quality.The O’Fallon Water Department tests 40 water samples monthly for bacteriological contamination at random locations throughout the system.
Independent laboratories conduct other tests for copper, lead, total trihalomethanes (TTHM), haloacetic acids (HAA) and other potentially harmful chemicals.
A consumer Confidence Report (CCR) is published annually and sent to all customers to advise them of water quality efforts and testing results.
A backflow and cross connection prevention program has been instituted to prevent harmful substances from siphoning into the water system.
Water and Sewer Billing Division Services
Answer questions about water and sewer accounts.
Offer assistance with leak investigations.
Provide free toilet dye strips to aid in discovering toilet leaks.
Act as cashiers for all City receipts.
Phone system operators for non-directed calls.
Provide general information to callers and walk-ins.
Process voter registrations.
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