Design and Analysis of Water Distribution Network Using EPANET and GIS for Pattanam Rural Area of Coimbatore District

Abstract

. Water distribution analysis and design is one of the challenging aspects in civil engineering which involves looping system of water distribution with extreme level of bursting pressure like lower than the atmosphere or much heavier pressure beyond the surge level due to differential elevations. The two major constraints that directly involved in major distributions are effective diameter of the pipe and permissible level of pressure at each nodal links/demand points. The paper deals with the planning of water distribution network through combined gravity and pumping looping system of network and satisfies the overall demand at each nodal point in and around the study area. The study area chosen is Pattanam rural area of Coimbatore district, Tamil Nadu. The population of the study area is 10,020. The present scenario in the study area is the presence of 9 overhead water tanks with average capacity of 40,000 litres. The feasibility of integrating the main supply with a single tank for the study area is checked. With the data obtained from field survey and data collection, a spatially bound model is created using ArcView GIS software. The output of ArcView model is then interchanged to EPANET input file with the help of interchange tool. This model is then imported in EPANET software. Keeping the flow and demand as a major factor and optimum diameter and pressure as constraints, a network is generated in EPANET software package. The output model from EPANET is checked for accuracy with manual calculation that is carried out using Hazen-William’s chart as well as with the field scenario. An integrated water distribution network model is thus suggested for the study area. The various tanks in the study area account for more head loss as well as more maintenance as many of the tanks are located to serve undeserved areas. Thus, a new tank location is identified foreseeing the further population expansion of the study area. The existing pipe line is maintained the same to the maximum extent except for some increase in diameter of pipes in the main line. The further scope of the project is the model creation and spatial analysis using GIS and water distribution system modelling packages integrating with GPS for more simplified and cost effective surveying, modeling as well as maintenance of the water distribution network system.