Hillingdon SuDS Design & Evaluation Guide

Detailed Design
9.12 Management of the SuDS landscape
9.12.1 The principles of SuDS
management
All designed landscapes require some level of
Importantly, where SuDS form part of a
management. Where maintenance is not
landscape (which would be present
carried out development will evolve towards
regardless of SuDS), this minimal attention
woodland or an urban wasteland.
should be considered as site care and not
dedicated SuDS care. The cleaning of gullies
This document introduces a ‘passive
and pipe work is not needed which reduces
maintenance’ approach for SuDS. This does overall management costs.
not imply no maintenance but rather that
much of the care for SuDS is site
Passive maintenance is therefore linked to
management rather than dedicated SuDS
integrated SuDS design.
maintenance.
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Hydrocarbons and other organic based
pollution such as which wash off hard
surfaces is broken down by natural processes
(passive treatment), within many SuDS
components meaning that there is no long
term build up of organic pollution. Heavy
metals and inorganic pollutants are trapped
within Source controls at low concentrations
and therefore form no threat to amenity
features or aquatic environments.
This is different to ‘intervention’ maintenance
which is required for conventional drainage
to remove toxic liquor from gully sumps or oil
and grit from interceptors and separators
which can be costly and in many cases not
completed, rendering the treatment function
redundant. Intervention maintenance can also
be required for SuDS to remove silt, however
through the use of source controls this
requirement will be minimised.
Hopwood Park MSA M42.
A light tracked excavator removes aquatic
vegetation to de-water next to the wetland,
before moving to a wildlife pile.
London Borough of Hillingdon SuDS D & E Guide
© 2018 McCloy Consulting & Robert Bray Associates