Measurements of perennial time scale in Lake Van, the biggest take with soda in the world, historical data, and the morphological changes in its coasts suggest that there is a continual rise in its level. The rise in the level of the lake which occurs under natural conditions averages 3.7 cm/year. This rate is not stable and it generally shows a parallelism in the fluctuations perennially. The measurements conducted in Tatvan show that this rise approximated to 2 meters (2.1 m) in 1944-2000. The swift rise, especially after 1987, has caused an environmental disaster in the coasts, inundating approximately 5200 hectares of land. Tens of villages together with Van, Tatvan, Ercis, Adilcevaz and Ahlat cities were affected, and thousands of houses, tens of thousands of acres of agricultural lands, highways, ferry harbour, historical sites, and wetlands in the mouths of streams, shelters of wild birds were damaged. In addition to all these, drinking waters, canalization network, urban infrastructure systems as well as some parts of Van Airport and many camping areas of holiday were reported to have been damaged due to the same reasons. In this investigation we aimed to determine the environmental consequences of level changes and the measures to be taken accordingly.