Wadis (Water Drainage Infiltration) are used ever more frequently in northern cities like Groningen and Leeuwarden as an ecological form of water management, especially for peak loads due to rainfall. Discharging rain water to low-level grassy fields relieves the sewer system. The water can infiltrate the ground more slowly and be retained there, counteracting desiccation. Wadis are also useful as ecological playgrounds for children, and for other purposes.
Another more technical solution is water-permeable pavement. This makes it easier for water to infiltrate the soil and be retained there during drier periods. This material is used increasingly in the redesign of streets and new public areas. Also, the majority of drainpipes have been disconnected from the sewage system, allowing rainwater to drain more slowly through infiltration. Where this isn’t possible, drainage transport has been installed for rainwater and groundwater. The pipe ensures that water can be released into the subsoil during dry periods.