Page 33 - Newham SuDS DESIGN & EVALUATION GUIDE

Concept Design 7.3 What Concept Design demonstrates 7.4 Concept Design process A topographical survey, expressed both as Concept Design

7.4.1 Flow route analysis
The SuDS Concept Design will demonstrate
Evaluation will begin with:
an understanding of how proposed
■
The natural hydrology, and the way that a
existing flow route analysis for the existing
development will impact on:
spot levels and contours, provides the basic
development affects how rainfall behaves on
site
■
a site, are assessed initially by flow route
template for existing and future flows.
the site and its natural hydrology
■
a modified flow route analysis for the
analysis.
Geology indicates whether rainfall will flow
■
historical drainage elements where these
proposed development.
from the site as runoff, infiltrate into the
are present
consider how a site behaves naturally before
■
these two ways.
the ecology of the site and its
■
development. This analysis can be applied to
Runoff collection – how rainfall is
surroundings Preliminary design will include: The first step in flow route analysis is to ground, or leave a site in a combination of
collected and conveyed to source control re-development and retrofit sites, and is Designers should be mindful that a site that
■ the landscape character of the locality features. informed largely by topography and geology. infiltrates naturally may not continue to
There may be a number of other factors infiltrate once it has been developed.
■ natural flow routes. ■ Source control – runoff managed as close
influencing the analysis, including:
as possible to where rain falls.
■ The management train – SuDS ■ historical drainage e.g. sewers or land
components and storage features linked drains
in series, which convey flows along ■ discharge locations
modified flow routes through the
development. ■ contamination issues
■ Sub-catchments – small discrete areas ■ existing landscape features
27 that manage their own runoff. ■ habitat considerations. 28
■ Maintenance – effective performance and The final treatment stage at Hopwood Motorway
reasonable care costs. Service Station. Monitoring has demonstrated
Australia Road, London, where permeable paving that water of a very high quality (near drinking
provides source control prior to SuDS Basins. water standards) leaves site.

London Borough of Newham SuDS D & E Guide © 2018 McCloy Consulting & Robert Bray Associates London Borough of Newham SuDS D & E Guide © 2018 McCloy Consulting & Robert Bray Associates