Detention basins, ponds and wetlands
Detention basins, ponds and wetlands
Site control - sustainable drainage systems (SUDS) for large areas
You can use source control sustainable drainage system (SUDS) methods to manage run-off at, or close to, the surface where rainfall lands.
You can use SUDS to manage the surface water run-off from larger areas, such as part of a housing estate, major roads or business parks. This is known as site control.
Source control measures alone may control the run-off from your site from showers or light rain. Persistent rain or heavy downpours will produce more runoff. Site control measures can prevent this from discharging directly to the water environment.
Detention basins
You can use detention basins to store run-off from large areas. They usually receive water from conventional drainage systems or from upstream SUDS.
Detention basins are dry except after heavy rainfall, when they will fill to hold large volumes of water. This allows pollutants to settle out before the water soaks away or discharges slowly downstream.
Ponds and wetlands
You can use ponds to store water for longer than in detention basins. This allows natural processes, including bacteria and sunlight, to break down pollutants before the water eventually enters downstream watercourses.
As well as being attractive features for urban areas, ponds can provide valuable wildlife habitat.
You should always create new ponds to treat run-off and never use existing ponds or wetlands. This will avoid damaging or disturbing the wildlife that is already in the area.
You can connect a series of ponds, or include wetland areas in measures to deal with run-off from large areas. Wetlands are well vegetated and can provide more treatment than ponds for contaminated run-off.
You can use newly created ponds and wetland areas to treat lightly contaminated water from farmyards and farm roads.