CS(AR)-219 : Simulation of operation of vellar system using HEC-5

Abstract

The program Simulation of Flood Control and Conservation Systems developed by the Hydrologic Engineering Center, USA and used in the present study, is a generalized software available for simulation of the operation of water resources systems. Also known as HEC-5, the program has been developed for simulation of operation of a system of reservoirs and diversions, being operated for flood control and conservation purposes such as water supply, irrigation, hydroelectric power generation. navigation and low flow augmentation. The program is useful in planning studies for evaluating proposed reservoirs and to assist in sizing the flood control and conservation storage requirements for each project. The program is also useful in selecting the proper reservoir releases throughout the system during the flood emergencies.

In the present study, the operation part of the Vellar river basin has been studied. The Vellar river basin is an important basin in Tamilnadu, a state of South India. The major reservoirs and regulators in the selected basin are the Manimukta reservoir, the Gomukhi reservoir and the Memathur regulator. A number of minor tanks & regulators are also available in the basin. The data used for this study have been taken from the report of "System Studies of Vellar Basin, Tamilnadu", prepared by Central Water Commission (1991). Because of lack of data, suitable assumptions regarding mandatory releases, municipal and industrial demands, irrigation return flows and capacity of equivalent tanks have been made. Detailed simulation studies of the system has been carried out using different index levels in two major reservoirs of the system, namely, Manimukta and Gomukhi.

The results of the simulation studies have been discussed in detail in the study. In general, it is found that water is not sufficiently available in the basin. Manimukta reservoir part of the basin has adequate reliability while Gomukhi reservoir part has significant deficits. Some conservation measures need to be adopted in Gomukhi reservoir part of the basin for efficient utilization of water resources.