The City uses ground water as the source of its water supply.  The City does not utilize a centralized water treatment plant.  Instead, water is treated at the well sites with fluoride, polyphosphates, and chlorine.  To ensure the safety of the water, samples are continuously tested at state approved laboratories.

The Water Division is the largest municipally-owned ground water system in Illinois.  Water is obtained from 32 wells (not the Rock River).  There are 28 reservoirs and two elevated tanks.  Annual production is 7.6 billion gallons.  Average consumption is approximately 16.7 million gallons per day, but the system is capable of producing up to 55 million gallons per day.

Water is drawn from the aquifers using 32 wells, which are generally evenly-spaced at 28 locations throughtout the City (average well density is approximately one well every 2.5 square miles).  The wells vary from less than 100 feet to more than 1600 feet deep.

Treated water is pumped from storage directly into the water distribution system using booster pumps.  In 2008, the City brought its first filtration plants on line as part of the water system improvement project.  At the conclusion of the project in 2012, there will be a total of 10 filtration plants. These plants are specifically designed to remove iron, manganese, and radium from our drinking water.