WATER CYCLE
Lakes and rivers
Cleveland and its suburbs draw water from Lake Erie's supply of more than 116 cubic miles of water, equivalent to 127 trillion gallons.

Water treatment
Water treatment plants purify lake water for consumption and supply it to homes and businesses. In Cleveland, this responsibility is that of the Cleveland Division of Water. The Sewer District and the Division of Water are two distinctly different agencies. While the District uses water-meter readings to determine customers' sewer bills, the two agencies are independent of each other.

Homes and industry
Once water is consumed by homes and businesses, it is discharged to the municipality's sewer system to be transported for wastewater treatment.

Collection system
The Sewer District operates and maintains more than 280 miles of interceptor sewers, which are trunk sewers that receive flow from municipalities' local sewer networks. While local communities are responsible for their own sewers, the District's interceptors transport that flow to one of the District's three wastewater treatment plants. Local systems are composed of separate sewers, which transport stormwater and wastewater in separate lines, and combined sewers, which collect both sewage and stormwater in the same pipe; many of the suburbs maintain separate sewers, but Cleveland relies on an aging combined-sewer system with pipes that are older than 100 years old in some areas.

Wastewater treatment
Our treatment plants operate 24 hours a day, seven days a week, treating more than 245 million gallons every day. Preliminary treatment removes large floating debris and grit; primary treatment relies on a settling process to remove remaining solid particles; secondary treatment uses active microorganisms to break down organic material and other pollutants; a disinfection process then eliminates harmful bacteria before the water is released back to the lake and rivers. In 2006, our plants treated and released more than 89 billion gallons of water to the environment.