Wastewater Treatment Department

The City of Norwalk's Wastewater Treatment Plant, located at 201 Plank Road, is designed to treat an average flow of 3.5 million gallons of wastewater a day, with a peak flow of 8.2 million gallons a day. The plant operates around the clock. 2018 average daily flow is 2.72 mgd.

Wastewater from throughout the city travels through a series of pipes and pumping stations into two 24-inch interceptor sewers that lead to the plant. The wastewater is subjected to a complicated treatment process before being released as clean water into the west branch of Rattlesnake Creek.


2018 CSO Annual Report (Click Here)

2019 CSO 4 Hour Event Notifications 6-5-19, 7-6-19, 7-18-19, 9-30-19

2019 CSO 7 Day Event Notifications 2-4-19,

2-6-19, 2-7-19, 6-5-19, 6-10-19, 6-12-19, 7-6-19, 7-18-19, 7-22-19, 8-6-19, 8-22-19, 8-27-19, 9-11-19, 9-30-19


Exposure to mercury can have adverse effects on one's health as well as the environment. Follow this link for information on how you can limit the risk of mercury exposure.