Where a development includes roads, these are often adopted by a statutory authority (for example the Highways agency or the local authority in the UK).
Where the authority will be taking responsibility for the roads, the following guidance should be followed to determine if the water run-off from the roads needs to be considered as part of the assessment:
- If the road drainage system bypasses the new development’s network to connect directly to the local drainage network, then the water running off from the roads does not need to be considered for this assessment. Evidence will need to be provided to demonstrate if this is the case.
- If the road drainage system connects to the development drainage network before connecting to the local drainage network, then the water run off from the roads must be considered for the assessment.
Where the authority will NOT be taking responsibility for the roads, the BREEAM criteria should be followed for all drainage on site.