Environmental Impacts of River Diversion: Gabcikovo Barrage System

An hydroelectric power system known as the Gabcikovo Barrage System was completed on a section of the Danube River between Hungary and Slovakia in 1996. Originally, the utilization of the river for hydropower production in the common reach was a joint goal of the two countries. Hungary voided the contract in 1989 citing potential adverse environmental effects of the project and Slovakia finished the project alone. To put the Gabcikovo Hydropower Plant into operation, the Danube River was diverted into a power channel in Slovakia in 1992. This paper presents the environmental impacts of the Gabcikovo Barrage System in the 6 years since the diversion, as detected and measured by Landsat satellite remote sensing imagery. The study area was limited to a part of the Szigetköz (Hungarian side) and Csallokoz (Slovakian side) region located between flood dikes. This is a unique wetland system with numerous river branches immediately downstream from the dam. The study concluded that a number of important, but limited, environmental impacts are detectable from the satellite imagery and so the imagery provides a suitable means of monitoring future changes in the region. This case study is the only known application of satellite imagery for assessment of the environmental effects of a diversion of a major river.