Date of Award

Spring 1-1-2016

Document Type


Degree Name

Master of Science (MS)


Civil, Environmental & Architectural Engineering

First Advisor

R. Scott Summers

Second Advisor

Chad J. Seidel

Third Advisor

Rajagopalan Balaji


Chemical agents in drinking water can pose significant human health risks. Evaluating the combined effects from multiple contaminants can provide new insights into how best to manage that risk and protect public health. The Relative Health Indicator (RHI) is a semi-quantitative metric developed to harmonize the cancer and non-cancer impacts from a wide range of drinking water contaminants, thereby allowing for comparison of the relative health risks posed by multiple waterborne constituents. The goals of this study were to use the RHI to assess the impact water age dynamics through distribution systems can have on population-based disinfection by-product (DBP) risk exposures and to evaluate the public health benefits afforded by several DBP control strategies.

Analysis of different network models revealed that system water age dynamics have a significant impact on population-weighted DBP exposures. As DBP regulatory compliance strategies, optimized coagulation processes and granular activated carbon (GAC) adsorption at the treatment plant were found to provide superior public health protection than GAC and aeration technologies applied within the distribution system when population-weighted RHI values were considered. The relative efficiencies of distribution system technologies tended to be equivalent to those applied at the treatment plant as evidenced by normalizing population-weighted RHI reductions to treatment process flow rates. Booster chlorination cannot be used to achieve DBP compliance but did demonstrate moderate population-weighted RHI reductions.