The City of Grinnell water is derived from five Jordan aquifer wells.
- Well #5 was drilled in 1920 to a depth of 2,220 feet.
- Well #6 was drilled in 1926 to a depth of 2,500 feet.
- Well #7 was drilled in 1955 to a depth of 2,500 feet.
- Well #8 was drilled in 1974 to a depth of 2,510 feet.
- Well #9 was drilled in 2002 to a depth of 2,378 feet.
Water treatment consists of force draft aeration, detention water in a 1.0 million gallon baffled detention tank for 10 to 11 hours, softening through four Zeolite media softeners, caustic soda is added for pH adjustment, polyphosphate injection for corrosion control, and sodium hypochlorite for disinfection. The plant has the capacity to produce 3.2 million gallons of water per day.
Pressure and storage for the distribution system is provided by a 300,000 gallon elevated storage tower located south of the water plant. The department has a stand by diesel motored generator which can be set up to pump water from wells #7, #8, and #9. The water plant also has a diesel motor that can pump water to the distribution system in case of any power loss.