New Delft Water Walk
The local Water Board (‘Hoogheemraadschap van’) Delfland was established in 1289. For more than 700 years, the Water Board has been keeping our feet dry and managing the water levels in a large part of the province South-Holland. The main tasks of the Water Board are to prevent flooding by building and maintaining levees, to manage the water levels in the canals and polders in the region, and to collect and treat wastewater. Ensuring good water quality is also an increasingly important task. Many people know the historic Water Board building ‘Gemeenlandshuis’ on the Oude Delft, which was built in 1505. However, the official entrance for the Water Board is actually on the Phoenixstraat.
Water Governance
The Executive Board of the Delfland Water Board is formed by the Chairman (Dijkgraaf) and five members of the ‘daily’ Board. This Executive Board is accountable to the General Board of the Water Authority, consisting of 30 members, 26 of whom are elected during the Water Board elections. The remaining four members are appointed and represent the interests of agriculture and nature. In principle, the General Board meets six times a year and elects the Executive Water Board members from amongst its members. The Chairman is appointed by the Crown. Meetings take place in the Gemeenlandshuis, where the Executive Board also works.
The Delfland Water Board is one of the 21 water authorities in the Netherlands and covers an area of approximately 41,000 ha, bordered by the North Sea, the New Waterway and an imaginary line along Berkel en Rodenrijs, Zoetermeer and Wassenaar. The border with the Rijnland Water Authority to north is formed by the Landscheidingsweg, which also takes its name from it. More than half of the area lies below NAP.
The Water Board is responsible for safe dikes, sufficient water (water quantity), clean water (water quality) and water purification. As such, the Delfland Water Board manages 743 km of dike, 170 polder pumping stations and 8 main canal (boezem) pumping stations. The canal pumping stations ensure a constant water level of 43 cm below NAP. This water level can be found in the major waterways, such as the Rijn-Schiekanaal (known in Delft as the Delftse Schie) and in the Delft canals. Locally, such as in the 60 polders in the area, the prescribed water level can deviate considerably from the main canal level. This prescribed level is regulated by the polder pumping stations. Deviations from the target levels can occur in the event of heavy rainfall, or prolonged drought and / or anticipation of such weather forecasts. The actual water level can be read on 700 gauges.
All that water flows through the 4,325 km long waterways, the quality of which must comply with the European Water Framework Directive by 2027. However, we are not there yet, a lot still needs to be done in the coming years.
The water quality is regulated by four wastewater treatment plants that treat approximately 7.5 million cubic meters of wastewater. That water is transported to and from the treatment plants by 33 sewage pumping stations through 165 km of sewer pipes. The sewer network of the city of Delft is connected to this.
Approximately 1.4 million people live in the area and there are approximately 40,000 businesses located there.
If you would like to read more about the Delfland Water Board and its tasks and activities, click here or here.
