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In most locations the water table is likely to studies and LLFA detailed requirements can
Local SuDS requirements
be found at depths of less than 3 metres. be found on Newham webpage as below:
Ground water source protection zones are LB Newham Flooding Webpage
found in the northern part of the borough.
Newham Local Plan
Flood Risk and Sustainable Drainage:
Requirements and Guidance for Planning
Application
Newham LLFA drainage pro-forma
Planning Application Requirements
Highlights of main requirements:
Fig.5 Newham’s main made ground
(grey/grey hatched) and source • All major development is required to
protection zones (shades of pink) restrict post development runoff to
greenfield run-off rates unless it can be
The combination of these factors may limit demonstrated that site conditions prohibit
potential for infiltration drainage. However,
the ability to do so.
given the high variability in ground conditions
found across the borough, it is recommended • All development must restrict runoff
that developers carry out thorough ground discharge within or to Critical Drainage
investigations to establish the potential for Areas (CDA) to greenfield rates or below.
N.B. there are 15 CDAs in Newham.
23 infiltration. It should be noted that none of • Discharge to tidal water (i.e. River
the above prevents use of SuDS within a
development, if integrated into the design at Thames, Lea and Roding) will need to
an early stage. In any case, above ground no take account of the effect of “tide
infiltration SuDS measures can still be used in locking”, storm surge or submergence of
areas of contaminated ground provided that the outfall, in order to prevent flooding.
barriers to contain contaminants, such as An appropriate allowance in terms of
impermeable liners, are used to protect onsite storage should be built into the
groundwater. drainage strategy.
• Discharge to tidal water may not be
Local SuDS specific requirements
restricted to greenfield provided scour/
Newham has developed a number of erosion would not result, however a level
documents in connection with local flood risk of attenuation will be expected - normally
assessment and management. Main a 1 in 30 attenuation - to create SuDS
requirements applicable to major features that provide additional benefits.
development are fully embodied in Newham’s Application of Greenfield Runoff Rates
local policy (Newham Local Plan 2018).
To enable consistency of assessment
Links to relevant Newham policy, flood risk
between planning applications, Newham
Newham Council SuDS D & E Guide © 2020 McCloy Consulting & Robert Bray Associates
