Water Treatment Plant

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Who we are

The City of Ithaca Water Treatment Plant has been proudly serving the City of Ithaca and a few surrounding areas since 1903. Located along a reservoir on Six Mile Creek, the facility provides safe, clean water to over 35,000 residents in the city area.

        Newly constructed City of Ithaca Water Treatment Plant, 1903.                                  City of Ithaca Water Treatment Plant, 2013. 


Six Mile Creek: Our Watershed

Six Mile Creek is more than just a beautiful waterway in our backyards. It is part of the Six Mile Creek watershed, an area that spans 46.5 square miles of mainly forested land. Its headwaters begin in the Towns of Caroline and Dryden. Click here to learn more about our local watershed. 

Bird's eye view of Six Mile Creek, Ithaca, NY. 

Making Your Water Safe to Drink

To ensure the highest quality possible, the City of Ithaca Water Treatment plant uses a six-step process to treat the water coming in from Six Mile Creek

  1. Pre-treatment- Chlorine and coagulating agents are added to the incoming raw water to disinfect and remove impurities. 

  1. Mixing- The water is rapidly mixed to distribute the treatment agents evenly. 

  1. Coagulation and Flocculation- The water flows into large basins where chemicals react with impurities in the water (coagulation), causing them to form larger, heavy clumps called 'floc' (flocculation.

  1. Sedimentation- The flocculated water flows into basins where these heavy clumps fall to the bottom.

  1. Filtration- Currently, the water flows through layers of anthracite coal and sand to further remove particulates. However, the facility will soon be upgrading to membrane technology, which is capable of removing even smaller particulate matter. 


                          Current Filtration Basins                                          New Membrane Technology  

  1. Post-treatment- Chlorine is added to prevent bacterial growth in distribution pipes, as well as a corrosion inhibitor that helps protect the distribution pipes. 

From Us to You

Water from the reservoir flows into the treatment plant by gravity. After treatment, finished water is distributed to the public through a distribution network consisting of roughly 85 miles of ductile iron and cast iron water mains ranging in diameter from 4 - 20 inches. The distribution system also includes three pumping stations and six water storage tanks. The final leg of the journey from the main in the street into your home or business is completed via a copper water service pipe 1/2 - 2 inches in diameter. 


 Links and Resources 

Here's a few helpful resources, including reports and overviews on drinking water: