Exploring the Use of Operational Interventions in Water Distribution Systems to Reduce the Formation of TTHMs

Abstract

Trihalomethanes (TTHMs) are water disinfection by-products whose consumption via drinking water may eventually be harmful for human health, as they could have carcinogenic effects, also for the exposure to them via non-ingestion routes [1]. In the present work the possibility to reduce the vulnerability of the population exposed to TTHMs by the optimal operational interventions in water distribution systems is explored. The proposed approach is formulated as a multi-objective optimization problem with two objective functions, the number of the operations and the maximum TTHMs concentration that occurs at each node in the network during time, both to minimize. The feasible operational actions concern opening/closing valves and hydrants and turning pumping stations for a fixed time. The AMGA 2 optimizer [2] is used herein for solving the problem, coupled with a module coded in C++, where the implementation of the EPANET Programmers Toolkit functions allows to run the hydraulic and water quality simulations and to calculate the objective functions.