Sustainable drainage systems (SuDS) are an approach to manage surface water in terms of flooding, water quality, biodiversity and amenity. SuDS reduce the reliance of traditional drainage and helps to deal with surface water runoff from hard impermeable surfaces.

In urban areas, SuDS work by slowing the rate that water enters the drainage network, helping to reduce the risk of flooding. SuDS can infiltrate into the ground or connect to a water body or stormwater sewer and typically include an attenuation system, often in the form of a surface pond, detention basin, swale, bioretention area or an underground tank, collecting the water during a storm and releasing it slowly back into the environment.

Within the SuDS attenuation system, mechanisms will release the stormwater at a manageable rate. By doing this, it prevents the drainage network receiving runoff from the development from becoming overwhelmed.

During periods of rainfall, the SuDS attenuation system will collect water and discharge it gradually. This releases water at a controlled rate rather than allowing peak flows to enter the downstream drainage system.

Surface water flooding is becoming an increasing concern, particularly as new developments modify greenfield, permeable land into impermeable surfaces. Climate change further exacerbates this issue by making storm events more intense and frequent.

Both of these factors can lead to significant increases in stormwater runoff volume and higher flow rates. This demonstrates the need for SuDS attenuation and treatment systems such as ADS StormTech.