Engineering Commons^™

Predictive Modeling Of Riverine Constituent Concentrations And Loads Using Historic And Imposed Hydrologic Conditions, Mark Hagemann

Doctoral Dissertations

This research was principally concerned with the task of quantifying dissolved and suspended constituents carried in river water when direct measurements are not available. This is a question of scientific and societal relevance, and one with a long history of study and a great deal of remaining difficulty. The traditional approach to estimating these quantities, linear regression models (LMs), suffers from poor flexibility and high subsequent bias in many applications. This research applied semiparametric generalized additive models (GAMs), a more flexible class of regression models, evaluated their performance in various locations and conditions, and applied them in a proactive modeling …

Proactive Assessment Of Climate Change And Contaminant Spill Impacts On Source Water Quality, Lillian C. Jeznach

Doctoral Dissertations

Managing the water quality of surface drinking water sources has become an increasingly difficult task for water suppliers due to increased watershed urbanization and climate change. Changes in source water quality may affect public perceptions, treatment effectiveness, and ultimately costs to treat water to drinking standards. Although there are increased threats to current and future drinking water quality, current approaches to managing these threats are typically reactionary. Prior detailed modeling efforts of hypothetical events that may impair raw water quality allow for an understanding of constituent fate and transport, including potential maximum concentrations and travel times to the drinking water …

Chromium Oxidation By Disinfectants And Oxidants Used In Drinking Water Treatment, Nathan D. Rogers

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This project investigated the behavior of hexavalent chromium (Cr(VI), a potential carcinogen) in drinking water. While Cr(VI) can exist naturally, it can also be oxidized from Cr(III), a known trace nutrient. Recently, the State of California implemented a water regulation specifically for Cr(VI) at 10 parts per billion (ppb). This project completed a comprehensive evaluation of chromium behavior when in contact with common drinking water treatment chemicals including chlorine, monochloramine, chlorine dioxide, potassium permanganate, and ozone.

The results of these oxidation experiments are highly applicable to water treatment facilities. If a treatment plant is using monochloramine, there is no indication …

Operational And Water Quality Analysis For The City Of Akron's Water Treatment Plant And Distribution System, Chelsea James

Williams Honors College, Honors Research Projects

Chlorination is one of the most common methods of treating pathogens and ensuring microbial water quality in water treatment and distribution. As chlorinated water leaves the source and travels through the water distribution system, the chlorine reacts with both the organic compounds (dissolved organic carbon, DOC) in the source water and the corrosion or biofilm of the pipe walls. The chlorine concentration, or chlorine residuals, at any point in the water distribution system is a good measure of water quality. At the same time, chlorination produces disinfection byproducts as the chlorine also reacts with other naturally-occurring materials in the water. …