A Real-Time Flood Forecasting Technique

ABSTRACT

A simple hydrologic technique is presented which is applied to short-term forecasting of floodflows at the outlet of a river basin by using rainfall information and water levels of the flood events at an upstream index station of the basin. The time of occurrence of the forecasted floodflow is also estimated. The applicability to real-time forecasting, the lack of any requirements for automatic network or for in-field computer facilities, the simplicity and the accuracy of the forecasting technique are its basic advantages—especially in a country such as Greece with a conventional hydrometeorological network and limited financial resources—in solving specific engineering problems. The flood forecasting technique is successfully being applied to the middle course of the Kalamas river in Northwestern Greece at a dam site during construction of the river's diversion for protecting lives of workers and equipment.

It should be noted that, where resources permit, the average basin rainfall between the upstream index station and the outlet of the basin could be better represented using more than one rainfall station. For some regions it is possible that the nomograms used for forecasting may need to be developed on a seasonal basis.