Date of Award


Document Type

Open Access Master's Thesis

Degree Name

Master of Science in Environmental Engineering (MS)

Administrative Home Department

Department of Civil and Environmental Engineering

Advisor 1

Brian D. Barkdoll

Committee Member 1

Kari B. Henquinet

Committee Member 2

Eric Seagren


Due to a variety of factors chlorination is common water disinfectant for community-scale distribution systems. The town of Suyo, Peru was already equipped with a gravity fed water system and drip chlorinator which achieved 4-log inactivation of viruses throughout the town, however, it was not providing 3-log inactivation of giardia cysts at all points of the system.

This project used an EPANET model to determine and compare the potential benefits of changes which could be made to the pre-existing water system in Suyo.

The model was used to compare current operating conditions of the Suyo system, 1.5 mg/L chlorine addition at the reservoir, with different potential operating configurations. To determine if there was a more efficient concentration of chlorine addition or point of chlorination, chlorination of different concentrations taking place at the reservoir and six other points between the reservoir and the town were modeled as well as the potential to chlorinate at two points simultaneously. To increase the amount of time the chlorine had to react with the water, the pipe between the reservoir and the town was modeled at different diameters.

Replacing the pipe between the reservoir and the town from the current 4” to 8” was found to raise Ct values and achieve 3-log giardia inactivation throughout the town. No benefit was found in moving the point of chlorination closer to the city nor in chlorinating both at the reservoir and at an additional node. Increasing the concentration of chlorination was found to provide 3-log giardia inactivation to a larger percentage of the town but did not provide full coverage for all users.