The organisation is a national service of the Directorate General of Public Works and Water Management (Rijkswaterstaat). It oversees the state and the use of the main water system in the Netherlands: the interrelated network of major rivers, canals, lakes, coastal waters and sea. From that perspective the organisation is practising an efficient and effective integrated water management, for the users, now and in the future. Knowledge and expertise provide and must safeguard a reliable, clean and safe main water system.
The service is the result of a merger end of 2007 of 2 former Rijkswaterstaat services, the National Institute for Inland Water Management and Waste Water Treatment (RIZA) and a part of the National Institute for Coastal and Marine Management (RIKZ).