Page 26 - Luton SuDS DESIGN & EVALUATION
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6.0 Local SuDS requirements for
Local SuDS requirements
Luton
Landscape Character formal surface water drainage (meaning
down pipes are discharging onto front or
Spread on just 43 km2 and with population in back yards and end up in the highway
excess of 200,000 Luton achieves densities drainage system.) All the above should be
higher than some of the London boroughs. taken into account when reviewing current
Bordered to the north and south-west by the drainage arrangements.
Chilterns Area of Outstanding Natural Beauty,
Luton is situated within the Upper River Lea Geology
catchment, with the source of the River Lea
placed within Leagrave Park in the northern The underlying bedrock geology of Luton
part of the borough. Tributaries of the River consists of chalk from the Lambeth Group
Lea, all classified as Main Rivers, include the Formation with glaciofluvial and alluvial
Catbrook, Houghton Brook, and Lewsey superficial deposits along the River Lea. Due
Brook. to the presence of extensive principal
aquifers; many being used for potable and/or
The topography of Luton generally slopes industrial water supply, source protection
towards the River Lea which flows in a south zones should be a consideration, especially
easterly direction through the centre of the when proposing infiltration.
21 town. The highest elevations are in the north-
west and the lowest in the southeast. The Although the national data sets indicate that
topography is steep in the upper reaches of the catchment soils are generally well drained
the Houghton Brook, Lewsey Brook and calcareous loamy soils over chalk and that
Catbrook and flattens out in the central the chalk geology underlying the urban area
catchment. In the southeast of the urban area is very permeable, detailed site investigations
of Luton the catchment becomes narrower show extensive superficial deposits
and the river is well defined by a steep valley. consisting mostly of clay, of variable depth
and special distribution, often at great
All watercourses are largely fed by surface distances from the river corridor.
water drains resulting in flashy responses to
rainfall. The modern scale and speed of Most of the watercourses in Luton are spring-
development (including infill) keeps putting fed, indicating groundwater levels at or very
greater and greater pressures on the rather close to the surface, especially in the
constrained, heavily modified chalk streams catchments of the Houghton and Lewsey
as well as the drainage network. Although Brooks. A number of perched aquifers had
majority of Luton is served by a separate foul also been identified in various locations
and surface drainage systems, there are across the borough.
pockets with combined sewers and/or lack of
Luton Borough Council SuDS D & E Guide © 2018 McCloy Consulting & Robert Bray Associates
