What is it?
Water storage is the practice of temporarily storing extreme rainfall in soil and vegetation. Vegetation eases the impact of precipitation on the soil and reduces and/or delays the flushing away of the water. This prevents erosion and drying. The stored water is gradually released again during dry periods, for example, or flows away to ground or surface water when there is prolonged rainfall. Life in the soil (e.g. through passages made by worms), organic matter and plant residues ensure that the soil better retains the water.
Soil can absorb water when extreme rainfall occurs. The big advantage of this function is that it prevents damage to homes, business premises and infrastructure. Also agriculture benefits, in ways including a continuous supply of water in dry periods.
Another advantage is that water storage is easily combinable with other services in a way that avoids space being used for just one purpose. For example, water storage may simultaneously yield recreational benefits (as nature areas), biomass and water purification.
In real life
A frequently heard water storage slogan is: retain, store and drain. Several examples can be mentioned of how to improve water storage capacity. They include:
- widening stream valleys can be beneficial to agriculture (provisioning services) and nature (biodiversity) functions;
- water retention can be improved by creating fewer hard surfaces in urban areas. Rainwater can infiltrate straight into the soil by using porous paving or by disconnecting the run-off of rainwater from the sewer system;
- water is storable on a bigger scale by creating ditches and ponds.