Hydrosystems strongly interact with society in terms of natural resource management, water quality/quantity management, or natural risks. During recent decades, population increase and economic growth, notably in flatter regions, have strengthened the tensions between hydrosystem functions and land planning. As a result, the importance of human impacts on hydrosystem functions and increases in hydrological risks are now widely recognised. The development of laws and policy tools to improve land and catchment planning in order to protect the natural functions and quality of hydrosystems has been one of the responses associated with solving these problems. In this context, the Water Framework Directive (WFD) of the European Union is heading and driving the national laws for European State Members. The aim of the WFD is to set a common standard in terms of quality and quantity objectives for physical, chemical and biological hydrosystem parameters. These objectives have to be implemented through an appropriate management plan and applied to every water body/water mass unit such as rivers, lakes and groundwater. These WFD objectives are challenging for a number of European countries that have highly inspired the WFD foundations from their own water management policies and tools.
