Effect of elevation to accuracy in water pipeline network simulation

Abstract

EPANET is hydraulic (pressure and flow) and water quality behavior (chlorine disinfectant) simulation software, developed by Lewis A. Rossman United States Environmental Protection Agency (EPA). Using “Gradient Method” as defined by Todini and Pilati (1987) to solve the flow continuity and head loss equation. It is kind of open-source, which can be developed further. Therefore, Metropolitan Waterworks Authority (MWA) of Thailand would like to use this software for pressure management of main pipeline network. MWA’s service area covers over 3 provinces; Bangkok, Nonthaburi, and Samut Prakarn. Each area has a different elevation. Recently, the pipe network model has used only two horizontal coordinates while without vertical coordinate or elevation. Thus, the error from model computation is still high. In this study the elevation of pumping station is changed using as-built drawing data that reference from Mean Sea Level (MSL). The elevation has been changed using estimation as each road surface level from Royal Thai Survey Department’s map. The improved model has accuracy about 88.76% higher than the existing model, about 17.92 %. Eventually this study is to show how important the elevation is in EPANET model.