ABSTRACT
Investigation and research of environmental problems are the daily issue of scientists and engineers of nearly all disciplines. Every environmental problem is direct or less direct attached to the hydrological cycle. Therefore the knowledge of this cycle and the hydrological information is essential for approaching environmental projects. This paper describes the information which is used to assess the hydrological cycle and its use in environmental related projects. It gives us the possibility how hydrological information is used in environmental impact assessment and describe the demand in investigate surface water acidification by acid rain.
