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Detailed Design 9.12 Management of the SuDS landscape
9.12.1 The principles of SuDS
management
Importantly, where SuDS form part of a
All designed landscapes require some level of
landscape (which would be present
management. Where maintenance is not
regardless of SuDS), this minimal attention
carried out development will evolve towards
should be considered as site care and not
woodland or an urban wasteland.
This document introduces a ‘passive
and pipe work is not needed which reduces
maintenance’ approach for SuDS. This does dedicated SuDS care. The cleaning of gullies
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.
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
139 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
Hopwood Park MSA M42.
be required for SuDS to remove silt, however A light tracked excavator removes aquatic
through the use of source controls this vegetation to de-water next to the wetland,
requirement will be minimised. before moving to a wildlife pile.
London Borough of Bexley SuDS D & E Guide © 2018 McCloy Consulting & Robert Bray Associates