Storing freshwater surplus in winter for use in the summer: it sounds easier than it is. Rainwater is ideal for watering due to the low salinity, but aboveground storage takes up a lot of valuable space. In an attempt to complement the available water, brackish or saline groundwater is often desalted through expensive reverse osmosis, or fresh water is brought in from elsewhere. Increasing freshwater shortages result in production losses for growers.

That is why the Dutch tomato growers of Prominent, recently opened a new demonstration project that showcases underground water storage.

Koen Zuurbier KWR demonstrates the water buffer

Underground water storage

The showcase water buffer is a unique demonstration of various techniques for local and regional underground water storage. One example is a system that stores excess rainwater through wells in the water-bearing sand layer, essentially creating a freshwater bubble in saline groundwater. The stored water can be used as irrigation water. This way, the injection and extraction of fresh water remains in balance, resulting in a robust fresh water supply, without the adverse effects of a salty waste stream (caused by reverse osmosis). The costs of desalination can be saved as well. This innovative way of freshwater storage can represent a major contribution to the prevention of freshwater shortages.

Since 2012, tomato grower Prominent has been storing the rainwater collected from four growers underground. This process is now used as a showcase, where all the steps are explained with information signs. In a special reception area, other techniques are demonstrated as well.