LARGE-SCALE WETLAND-RESTORATION OF THE RONDE-VENEN, THE NETHERLANDS

For the area of the Ronde Venen a plan for large-scale wetland-restora tion and improvement of the water quality was developed. Major element s of the developed spatial strategy are the optimal use of the specifi c hydrological and ecological characteristics of the area. Based on re gional hydrological characteristics within the study area hydrological sub-units were distinguished by connecting discharge and recharge are as. In this way the intake of polluted surface water from outside the area could be minimized, with an optimal use of specific local differe nces in water quality. Two scenarios were developed and evaluated usin g hydrological, hydrochemical and ecological models. The scenarios dif fered in spatial composition and the way the water level was manipulat ed. In order to optimize water quality, natural and artificial polluti on control mechanisms were implemented as well. An important criterion for the evaluation was the extent to which the scenarios succeeded in optimizing conditions for the realization of the ecological goals. Th e most promising and acceptable scenario has been worked out in furthe r detail.