How does the dirty water you flush down a toilet get cleaned safely before it's released to the environment? That's the work of a wastewater treatment plant. The Northeast Ohio Regional Sewer District, headquartered in Cleveland, operates three such plants, including the largest in Ohio. Let Wally Waterdrop take you on an up-close-and-personal tour of the treatment process. You can also find more information at neorsd.org and wheredoesitgo.org.