Climate study on future fresh water demand in the western part of the Netherlands
Province of South Holland
Government
the Netherlands
Spatial development and water management
Due to climate change the western part of the Netherlands is confronted with an increasing demand for fresh water. In addition summers will be dryer and surface water is becoming more saline. The latter is caused by an increase of upward seepage of brackish groundwater in deep laying polders and by seawater intrusion in the branches of the river Rhine. The area used to have abundant fresh water resources. Now it is confronted with an increase in fresh water demand and a decrease of fresh water resources. Fresh water is becoming scarce.
In the study the increase in fresh water demand towards 2050 is elaborated using water balances. In addition the changes in water quality are studied. For a number of pilot areas detailed forecasts were made for 2050 hydrological conditions using rainfall-evaporation time series derived from the climate scenarios of the Dutch national meteorological institute (KNMI). The increase in water demand varies with time. In the most critical period an increase up to 20 percent is expected in 2050. The results were discussed with representatives of pilot areas and high potential measures to adapt to dryer and more saline conditions were defined, with focus on measures to improve the self sufficiency op the regional water system.
However, the possibilities for measures for improvement of the self sufficiency of the regional water system appear to be limited. It is therefore concluded that the water supply of this part of the Netherlands in dry periods is highly dependant on the possibilities for water supply from the main river system in the Netherlands.
The results are input for a nation wide study. The national study is part of the Delta-program and will result in a proposal for the nation wide distribution of fresh water from the main river system in dry periods. A so-called delta-decision by the central government for freshwater supply and salinization control, including the required infrastructural measures is expected in 2014.