Sustainable Drainage Systems (SuDS)

SEL are committed to researching and developing engineered solutions to meet the increasing requirement to incorporate SUDS within new development. As you are no doubt aware, the majority of the UK's drainage and sewer systems are archaic and operating at maximum capacity, unable to cope with the increasing amount of runoff from the continual development of new sites for housing and industry which is capping off soft landscaping. The rainwater caught on roofs and hard paved areas cannot permeate directly into the ground as when the land was undeveloped. Normally this water is channelled using pipe networks and discharged directly into the nearest sewer or adjacent watercourse. This increases the volume and levels within these to the extent that the incidences of flooding are on the increase.

The result is damage to property and erosion. Water quality can also be affected by the increase in water quantity. Where the runoff drains are connected to a combined sewerage system, the increase in flow can be too great for the sewer to cope with. This resultant flooding of the sewer can contain faecal material and other pollutants.

Current practise of local authorities and the EA is to restrict the level of discharge into the existing sewers and watercourses. This addresses the problem of overloading the sewer or local watercourse but the suppressed rainwater has to dealt with on site at source.

SEL Environmental can design, supply and install solutions incorporating a range of innovative stormwater source control technologies to combat the problem at source.

These include:

Storage

  • within a pervious constructed surface.
  • in conveyance systems i.e. sloping channels or oversized pipes.
  • in permanent ponds or basins that only fill up during storms and then drain away slowly.
  • in the form of shallow attenuation tanks positioned close to the surface using a orifice plate/flow control device to limit disharge.
  • light-weight sub-base replacement storage systems.
Treatment
  • permeable pavement sub-base and filter drains.
  • grassed channels and filter strips.
  • infiltration devices, via a permeable pavement, using geosynthetic units to form soakaways.
  • standalone systems to re-use stormwater for toilet/ urinal flushing.
  • shallow oil/contaminant interception and treatment systems.

 
SEL have in-house design capabilities and testing facilities and are continually investing in the development of validated package solutions utilising the above techniques to achieve a more sustainable approach to overcoming the increasing problems associated with the existing urban drainage network. This unique approach has the benefit of ongoing partnering with several leading academic institutions and specialist external consultants.