SuDS in London - a guide

Rill and de-paving
This has reduced local authority
utilities and maintenance costs and
increased the attenuation storage
capacity of the streetscape. Water
treatment capabilities also feature,
due to the oxidative capacity and
bacterial activity of the retention basin
• Swales with 4,500m³ of vegetation
increase the attenuation storage
capacity. These have been integrated into
the reconfiguration of the carriageways
to create vegetated separation between
carriageways with different functions.
This has significantly enhanced
biodiversity in the streetscape
• Soakaways have increased the infiltration
rate by aiding conveyance of water into
the ground, contributing to the 1300m
attenuation capacity of the scheme
• Trees have mitigated urban heat island
effects by increasing the interception
of solar radiation and increasing
evapotranspiration. Tree planting has
contributed to the effectiveness of the
SuDS scheme and helped reconfigure
the streetscape by creating a separation
between carriageways and enhancing
the sense of place. Sensors have
been installed to quantify the cooling
effect provided by the vegetation
Benefits
• Reconfiguration of carriageway
to align with Grand Lyon’s
sustainability objectives
• Provision of extra parking for taxis,
deliveries and public road users
• Creation of new green links through Lyon
• Re-purposed existing infrastructure
• Peak outflow into the combined
sewer system is 5 L/s/ha
• Monitoring during the first phase of
construction has helped inform the
development of phases two and three
• On-site availability of recycled
water for street cleaning
• Automated irrigation reduces
maintenance commitment and cost
• Water and air treatment capability
Lessons learned
• Ensure clear agreement between local
authority services for management
and maintenance responsibilities
on cyclical and periodic regimes
122 5 Case studies