Sustainable Urban Drainage and sub-layers
In the UK, there isn't a national requirement for all schools to be SuDS (Surface Water Drainage and Erosion Control) compliant. However, some schools and educational institutions are incorporating SuDS principles into their designs or implementing SuDS-friendly measures.
The Royal Institute of Chartered Surveyors (RICS) has published guidance on the design of educational facilities that incorporates SUDS principles to manage flood risk and improve water quality. This guidance is not mandatory for all schools, but it serves as a best practice recommendation.
That being said, some schools and local authorities are adopting SUDS principles in their design or maintenance plans due to various factors, such as:
1. Local Flood Risk Assessments (LRAs) that require schools to mitigate flood risk.
2. Water quality improvement initiatives aimed at reducing stormwater runoff and improving water bodies.
3. Sustainability and environmental considerations.
Some examples of UK institutions that have adopted SUDS principles or implemented green infrastructure include:
* The University of Cambridge, which has incorporated green roofs and rain gardens into its campus design to manage stormwater runoff.
* The Royal Horticultural Society's (RHS) garden at Wisley, which features a permeable paver system to reduce stormwater runoff and improve water quality.
* Local authorities, such as the London Borough of Croydon, which has implemented SUDS measures in school playgrounds and flood defenses.
It is essential to note that specific requirements for SUDS compliance can vary depending on factors like location, local regulations, and the school's flood risk status.
MOT (Ministry of Transport) type 1 is used to create an easily compacted base layer. The thickness of the MOT type 1 sub-base will depend on the site ground conditions andcan vary from 100mm to 300mm. It must be compacted in layers no more than 100mm.
If there is a specific requirement for the sub base to be SuDscomplient, an MOT type 3 aggrogate blend should be used. It should be noted that it is harder to compact MOT type 3, so sub base wash out may occur long term.
