If you operate a drinking water treatment plant or purchase from one, then you probably have heard about disinfection byproducts (DBPs). How Disinfection Byproducts (DBPs) are formed is simple to understand. Raw water entering the treatment plant contains organic matter. The level of treatment provided and the nature of organics in the raw water will determine the level of organic removal at your treatment plant. The organics remaining after treatment react with chlorine used for disinfection. Once chlorine comes in contact with organics, DBPs begin to form. This reaction isn’t instantaneous and relies on several factors including time, temperature, and the pH of the water. Therefore, DBPs not only form at the water treatment plant but continue to form in your water distribution network. Below is a simple diagram of the process.
Many systems have struggled controlling DBPs and rules have changed making it increasingly more difficult to meet EPA’s minimum standards. DBPs are made up of trihalomethanes and haloacetic acids each of which are a grouping of several different chemicals. For instance, trihalomethanes are a group of four chemicals which include chloroform, bromodichloromethane, dibromochloromethane, and bromoform. Each chemical is different and it is imperative to understand the options available for removal of the contaminant. Some require simple treatment techniques while others can be much more difficult and costly to remove.
At CGE we have years of experience in water treatment and have worked with cities across Oklahoma to find the simplest and most cost-effective option available to reduce DBPs from drinking water. A holistic approach to distribution system management is necessary to meet the requirements of the Safe Drinking Water Act. Source water quality, water treatment and distribution management are all necessary. If you need assistance with your system, please let us know and we would be happy to assist you.
This week's author is one of our Project Managers, Tim Ward, PE. Mr. Ward has more than 25 years of experience working with municipalities and industry in the design, construction and financing of drinking water and wastewater facilities. Prior to joining CGE, Tim was Assistant Director for the Water Quality Division of the Department of Environmental Quality.