Before the Pipe: Monitoring and Modeling Disinfection By-Product Precursors in Drinking Water Sources

In lakes and reservoirs that serve as sources of drinking water, a portion of organic carbon reacts with disinfectants such as chlorine to form disinfection byproducts (DBPs). DBPs are a public health concern because they are potentially carcinogenic or mutagenic. The "Before the Pipe" project is a collaborative effort to assess the state of the knowledge on DBP precursors at their sources. Much of the available literature focuses on water treatment, but we want to understand what is happening in watersheds and receiving waters (rivers, lakes, and reservoirs) before treatment. Topics identified at GLEON19 include:

• Define the drivers, processes, and sources of DBP precursors.
• Identify the best proxy measurements for quality and quantity of organic matter and DBP formation potential.
• Determine what to measure (field, laboratory), when to monitor, and how to analyze (chemistry/data).
• Describe the key variables for modeling and possible modeling approaches.

The primary goals of the project are: (1) Evaluate the state of the knowledge through literature, data, and case studies to build understanding and fluency on topics that relate to organic carbon and DBP precursors that affect water supply and identify knowledge gaps; and (2) discuss opportunities for future research and collaboration. The ultimate goal is to provide tools to managers to support prediction and risk assessment for DBPs prior to drinking water treatment and delivery to consumers.We invite those who are interested to join us. We will discuss initial steps in a kick-off online meeting in March 2018.