In some cases, the existing system is insufficient to cope with the amount of rainwater. This may be due to housing development, if several systems intersect or if rainwater storage requirements cannot be met with the existing solution. For these and other situations, a central buffer is the perfect solution.
Using a central buffer, the water is drained from a surrounding area towards a central place. This is often a car park, square or park. The rainwater from the surrounding area is captured at this central place and infiltrates either into the groundwater or by gradual discharge to the sewer system.
The size of this type of solution varies widely, depending on the storage requirements and the surface area that needs to be decoupled from the sewer. That surface area can range from a single building to part of a residential area.