In 1992, the Greater Cincinnati Water Works (GCWW) opened the door to a new era in drinking water treatment by using innovative Granular Activated Carbon (GAC) technology to remove a broad spectrum of organic chemicals from the Ohio River.

The Ohio River, which is a heavily traveled industrial river, is the source water for the Richard Miller Treatment Plant. Over the years, several major spills have occurred.  These spills threaten the quality of GCWW's finished water.  GAC technology with our convention treatment and filtration process enables us to remove a broad spectrum of organic contaminants from the river.

In addition to the removal of organic chemicals, the use of GAC technology has reduced the amount of chlorine necessary for disinfection.  In 1991, before GAC was installed, 692 tons of chlorine was used compared to last year when only 254 tons of chlorine was needed.   The Disinfection-by-Products were significantly reduced as well.  While many knew that GAC technology would be a broad spectrum treatment and we expected that it would remove a wide variety of organic chemicals, we were pleasantly surprised to learn it helped with disinfection.  The extra filtration ensures that GCWW will continue to comply with current and planned compliance regulations. 

A unique feature of the GAC facility is that it was designed to reactivate the carbon on-site using two multiple-hearth furnaces.  The furnaces operate at temperatures ranging from 1600 to 2000 degrees.  The furnaces thermally recharge and restore the carbon’s virgin adsorptive capacity so that it may be reused cost-effectively.  GCWW operates the furnaces from May through November to take advantage of the lower natural gas prices during this time of year.

Fifteen years of research, planning, design and construction went into this project and has assured that GCWW set a national precedent for cost-effective, health-conscious, environmentally safe drinking water.  For more than ten years, GCWW has operated the largest GAC filtration facility at a drinking water treatment plant in the country.  GAC filtration is the Best Available Technology as recognized in the Safe Drinking Water Act.  Members of GCWW contribute to the development of AWWA standards covering the use of GAC as a filter medium and adsorbent in water treatment, and the use of reactivated GAC for water treatment.  Due to our on-site reactivation, GCWW remains a pioneer in this field.