AWWA ACE65589

This powerpoint presentation begins by providing a brief overview of the F.J. Horgan Water Treatment Plant, one of four City of Toronto water treatment plants (WTP). The history and early warning signs of a taste and odor (T&O) event at Horgan WTP are outlined, along with a feasibility study from 1999 that examined different treatment options, and recommendations from the study to use a combination of treatments for T&O problems including using powdered activated carbon (PAC) on half the plant equipped with flocculation tanks and replacing anthracite media with 950 mm granular activated carbon (GAC) caps. Shortcomings of using GAC/PAC at Horgan WTP are listed, and a new opportunity for T&O upgrades is presented that involves the use of ozone. Major advantages and design of an ozone system are provided.