Sustainable Drainage Systems (SuDS) - Alleviating demand on water supplies and future flood risk
In the North West of England, a lack of rain and a large reduction in reservoir levels means that the Environment Agency has been preparing for a drought and although the scheduled hosepipe ban for early August has now been cancelled, it would have affected around 7 million people. In the future, as a result of climate change, this may become more common, with experts predicting wetter winters and hotter, drier summers. Therefore, it is important that we all do as much as we can to reduce demand on water supplies.
Households and businesses in the UK can do more to reduce the demand on water supplies, and one option is to install SuDS which would allow rainwater to be harvested all year round. Rainfall can be collected in water butts and can reduce the reliance on water supplies during the summer months. The rainwater collected can be used during the summer and in periods of drought, for numerous different purposes, such as toilet flushing, irrigation or watering plants. Not only is this better for the environment in terms of water availability and usage, it can also help to reduce your household’s water bills and reduces the risk of flooding in the wetter months.
SuDS offer a more natural approach to managing drainage in and around properties and developments, in comparison to traditional drainage systems. They are designed to temporarily store water during storm events, to reduce peak flows and to reduce surface water runoff, through mimicking the natural cycle of water management. One type is source control, which deals with water where it falls (the source) and reduces the volume of runoff from a particular site by intercepting water and increasing storage and infiltration. Therefore SuDS can help to reduce the risk and impact of surface water flooding as they decrease the amount/volume of water falling onto hard surfaces and entering our drainage systems.
With the population set to rise by an estimated 8.7 million in England by 2050, it is critical that enough homes are built with adequate and sustainable drainage to reduce the demand on water supplies and to reduce the risk of flooding. Currently, 4.48% of homes in England are at risk of flooding, with this set to rise by 129% (2.5 million homes) in 2050.
It is important to think about where the rainwater that falls on your property ends up, for example, if your property or premises has a lot of impermeable paving, water will run off this and into drains rather than being absorbed into the ground, as would happen in a natural drainage system.
In the last ten years, 22,000 hectares of green space has been lost and turned into hard surfaces. Both homeowners and business owners can retrofit SuDS into their properties, putting less strain on drainage systems and water supplies and reducing the property’s flood risk. However, it is a lot easier to implement SuDS during the design stage of a development and following a new planning policy released in 2015, SuDS should now be provided on all developments (residential, non-residential or mixed). Some examples of SuDS include green roofs, rain gardens, detention basins and permeable surfaces.
For more information on SuDS and the different types, please download our SuDS Booklet here.
Sources used: Environment Agency, Sustainable Business Forum – Bricks and Water Policy,