DT117/4 Sustainable Build & Design - Class Presentations

1. Sustainable Drainage Systems: Above ground attenuation Thomas Geoghegan

3. Background on SUDS

5. Selecting the best SUDS option

6. Selecting the best SUDS option When selecting Sustainable drainage systems it important to consider Quality, Quantity Amenity Equally

8. Above ground attenuation options Basins and ponds Filter strips & swales

9. Above ground attenuation options Basins and ponds Basins are areas for storage of surface runoff & are free from water under dry weather flow conditions. These include: - Flood plains - Detention basins - Extended detention basins Ponds contain water in dry weather and are designed to hold more when it rains. They include: - Attenuation ponds - Flood storage reservoirs - Lagoons - Retention Ponds - Wetlands

10. Above ground attenuation options Basins and ponds Basins and ponds store water at the ground surface as: - Temporary flooding - Flood plains - Permanent ponds

11. Above ground attenuation options Basins and ponds Quantity They store floodwater and release it slowly once the risk of flooding is over Quality Treat: - Settlement of solids in still water - Conditions and promotes settlement - Adsorption by vegetation of soil Amenity Offer: - Sports and recreation - Wet ponds are great to store water for reuse

12. Above ground attenuation options Filters strips & swales Filter strips and swales are vegetated surface features that drain water evenly off impermeable areas. Swales are long shallow channels whilst filter strips are gently sloping areas of ground.

13. Above ground attenuation options Filter strips & swales They work by imitating natural drainage patterns by allowing rainwater through vegetation, slowing and filtering the flow. Quantity Swales & filter drains are designed for: - Conveyance systems - Infiltrations - Reduce drained impermeable areas Quality Swales and filters remove polluting in the solids through filtration and sedimentation

14. Above ground attenuation options Filter strips & swales Amenity Swales and filters trips are often interpreted into surrounding land use Examples are: - Public open space - Road verges - Grass and flowers can be planted for wildlife

15. Case Study Matchborough School

16. Case Study Location : Redditch, Worcestershire, England Description : A school development was designed with conventional drainage that flowed to a pump station from where it was pumped to a sewer During construction one playground area could not be drained by gravity to the pumping station. Main suds used: Swales Detention basins

18. Case Study Swales collect overland flows from: - Adjacent site - Runoff from car park - Playgrounds - Hence providing source of control The retention basins drain the main driveway that is connected to a constructed wetland (pond) which also takes runoff from the roof. Car park Inlet

19. Case Study Benefits The suds system has brought a valuable amenity and teaching resource for the school

21. Any Questions?