COASTAR: saline at bay, fresh on hand

In the COASTAR (COastal Aquifer STorage and Recovery) project that recently got underway, KWR, together with Deltares and Arcadis, is researching the feasibility of the large-scale subsurface storage of freshwater in the region of The Hague-Westland-Rotterdam. In a delta with lots of saline water, freshwater is scarce. The growing demand for freshwater coupled with its decreased availability as a result of climate change, requires that measures be taken. This research, commissioned by the Province of South Holland and Dunea among others, will provide insight into a complementary or alternative manner of water management on a large scale.

Large-scale use of the subsurface for storage and supply of freshwater

Increasing water demand, climate change and rising relative sea-levels all contribute to salinisation in coastal areas, leading to shortages of freshwater for drinking water, agriculture, nature and (urban) water management. This forces us more and more to turn to expensive alternative solutions for water supply, such as desalination (seawater) and the transport of scarce freshwater over long distances. Moreover flooding is also a growing concern. Because of this set of problems, the business climate in coastal areas is becoming less and less attractive. The use of freshwater surpluses after their temporary storage in the subsurface, and the use of upwelling brackish water, are currently still seen as small-scale initiatives that can only be applied by end-users at a local level. And the linking opportunities they offer for further water management are still barely taken advantage of.

Exploring COASTAR in the economic heart of South Holland

We will begin this TKI project by systematically and critically researching and developing COASTAR. Besides paying attention to the subsurface and the techniques, we will focus sharply on the costs and benefits, financing and organisation. The targeted result is a Master Plan for a COASTAR implementation programme for the region of The Hague-Westland-Rotterdam. This Master Plan will serve as a model for other regions in the Netherlands and coastal areas worldwide.

The ultimate goal of this TKI project is the recognition of COASTAR as an adaptation strategy by the regional and national authorities. To make it possible to strike the right balance between COASTAR and other freshwater supply options in low-lying areas of the Netherlands, the links between COASTAR and ongoing government programmes, such as the Delta Programme, will be actively established.

ASR Prominent: ‘Freshwater supply in Westland greenhouse horticulture: one of the components of COASTAR’.