SUDS Water Entry/ Surfacing Options
Pervious pavement surfacings
Aggregate Industries has developed a range of
pervious pavement surfacing materials designed to allow water to
pass through the hard landscaped surface into the water storage
layer below.
Charcon Infilta Block Paving
– Charcon Infilta is a rectangular permeable block paving system,
incorporating a 5mm spacer design. Each interlocking unit with its
specially designed nib structure provides a 5mm void, allowing
ingress of water through to the sub base storage system. With more
than one million square metres installed, permeable concrete block
paving has an extensive track record as an effective sustainable
drainage system providing direct infiltration, filtration and
treatment of daily effluent loadings associated with car park
run-off.
Charcon Grassgrid – is a high
strength, interlocking cavity grid system, which can be used to
create natural looking areas of permeable hard standing.
Bardon DrainAsphalt -
Aggregate Industries’ research programme into Sustainable Drainage
solutions has led to the development of Bardon Drainasphalt
surfacing. A range of purpose designed open-graded aggregate
structures bound with a polymer modified binder to form a matrix
with interconnecting voids through which water can pass. When used
as a component in a Sustainable Drainage System the porosity of
this material allows for surface water drainage either into
attenuating underlying reservoirs or by infiltration through a
porous pavement structure.
Bardon Drainasphalt is available in a range of
sizes: 10, 14 & 20mm to suit a range of thicknesses dependent
on schemes requirements
Bardon Hydrain – is an
innovative and versatile new addition to the Bardon Concrete range.
This porous concrete has an evenly-voided structure and is
available in a range of aggregate sizes depending on application.
Mix designs are available for both surface course or base layers,
with the added advantage of utilisation as a structural replacement
for traditional granular sub-base when poor ground conditions are
encountered.
Charcon permachannel - flexibility to use conventional,
impermeable surfacing materials
Combined collection and silt/oil separation
& treatment channel
Charcon Permachannel™ - is a unique product
which integrates with conventional impermeable hard surfaces to
convey rainwater into the Charcon Permavoid™. Charcon
Permachannel™ is a combined run-off collection, silt/effluent
interception and treatment system. This source control system has
been installed successfully in numerous large scale developments.
The Permachannel is designed to prevent the development of lateral
velocities, thus its initial function is to ‘still’ the sheet-flow
from each sub-catchment and to encourage silt deposition along the
length of each channel. The outlets discharge from the side of the
channel via a weir & baffle component, which separates oils and
prevents the effluent and silt from progressing beyond the channel
into the rest of the drainage system.
The design of the system incorporating Charcon
Permachannel will be based on several inputs including catchment
area and run-off volume to determine silt and effluent loadings
that can be treated in accordance with PPG3 guidance on treatment
levels. The key benefits of this form of interception and treatment
at source is the prevention of the development of high silt and
effluent loadings within the drainage system, typical of
conventional end-of line interceptor/separator systems.
Consequently the effluent loading within the channels is very low
and hydrocarbons are degraded within the channels by natural
aerobic processes. Furthermore, due to the instant velocity
control, emulsification of oils is dramatically reduced. The
designed effluent treatment levels are well within PPG3
requirements and outperform Class 1 interceptors/separators. Silt
loading calculations generally incorporate significant redundancy
to take account of potential long-term (several years) maintenance
neglect.
Other charcon products
When using Charcon Permachannel, impermeable
Charcon products can be used, such as Andover and Woburn blocks and Appalachian
flags. Natural stone can also be used. This
system allows the designer to incorporate a highly aesthetic
appearance or adapt to planning requirements.