Fresh water is vital to accommodating an urban population in its residential, industrial and recreational needs. At land reclamations, fresh water cannot always be supplied from the mainland, simply because many coastal megacities already suffer from increasing freshwater shortages due to urbanisation and ongoing climate change. This leaves desalination as only alternative for the freshwater supply of most land reclamations, but this technique is expensive and highly energy consuming. Building freshwater storage capacity on the land reclamation is an alternative. Collecting rainwater, using treated wastewater or storing desalinated water are options. With a considerable storage, the land reclamation is made less dependent on supply from the mainland or on desalination. This is profoundly important in the light of sustainability and climate adaptation.
The possibilities for storage above ground are minimal, due to the high land prices and the high costs involved with aboveground storage tanks. Subsurface storage, on the other hand, has a minimal footprint above ground and utilizes the large space that is available in the subsurface of the land reclamation. Its conserving qualities both with respect to evaporation and water quality make subsurface storage of fresh water attractive compared to above ground storage. Moreover, fresh groundwater, if accessible to plants and trees, will immediately enhance the image of the new land in a natural way. All these benefits ensure that subsurface freshwater storage and recovery potentially increases the robustness of the water supply and the quality of life on land reclamations.