GPSJ Autumn 2024 ONLINE - Flipbook - Page 25
FORMA - COVER STORY
the system’s attenuation volume
across sloping ground.
The surfacing was completed
with permeable asphalt in the
parking areas and impermeable
asphalt on the vehicle circulation
route.
Right solution ‘critical’ MAG
The Forma solution is already
performing very well. It has
exceeded expectations in terms
of structural stability, achieving in
excess of 80% CBR (a standard
aggregate strength test) on top of
the subbase.
This is very extremely
impressive for a permeable opengraded subbase system, with
much of the stability created by
the Formavoid raft.
The system is design to
attenuate a 1 in 100 year storm
with an additional safety factor of
40% for future climate change.
Importantly, the Formavoid
subbase is the ideal environment
to intercept, contain and
biodegrade hydrocarbons, as
proven by many studies on
pervious pavements.
So pollutants are removed
from surface water before it
is discharged into the stream,
eliminating the need for expensive
interceptor tanks.
Olivia Hughes, Senior Project
Manager at MAG, pointed out:
“Due to the sta昀昀 car park being
adjacent to a site of special
scienti昀椀c interest, it was critical
that we did the right thing.
“The Forma system has been
bene昀椀cial to MAG because it
allowed us to only excavate to a
shallow depth. It’s also a carbon
GPSJ
zero product so we are reducing
our emissions.”
Attenuation system of
choice
The modular design of Forma
will allow MAG to continue to
implement the system in phases.
For example, the rest of the
car park could be upgraded in
2,000m² sections.
This aligns the solution
with capital availability allows
maximum 昀氀exibility to keep car
parks operational. Forma is a
progressive solution. Every square
meter installed is a progressive
improvement.
The project has also delivered
many other advantages for MAG:
• The solution streamlined and
simpli昀椀ed all elements of a large
attenuation installation project.
• Much less material was
excavated and moved, which
saved signi昀椀cant costs.
• It also dramatically collapsed
the project’s carbon footprint.
• Fewer truck movements meant
less air pollution and improved
road safety.
• The construction method was
safer, as well, with no con昀椀ned
space entry.
• The project was completed
much faster than a traditional
tank-based solution.
In limited scenarios, installing
large tanks will remain the only
water attenuation option available.
However, shallow attenuation,
as demonstrated by Formavoid
at Manchester Airport, is ready
for take-o昀昀. And will be the
attenuation system of choice. For
a lot of very good reasons.
Giving SuDS compliance a sporting chance
The Forma system is not just
changing minds about water
attenuation in the world of
airport management or car park
design.
It can be applied to many
other water management
challenges. For example,
a Formavoid raft has been
installed below the playing
surface in a new stadium
belonging to one of the UK’s
most prestigious sports clubs.
Forma, based in Blackpool,
Lancashire, is working with
partners to widen its use to
create the perfect drainage
systems for the most highpro昀椀le sporting arenas across
the world.
Storing water for reuse
Forma Director Jack
Shuttleworth said: “The
technology is ideal for
controlling conditions needed
to optimise grass growth and
health, as well as installing
modern hybrid playing surfaces
that combine grass and other
materials.
“Forma attenuation systems
can also be combined with
a wide range of permeable
and non-permeable surfaces
in public spaces, like school
playgrounds and play areas,
sports centres, parks, and city
squares.”
What is more, the water
can be stored and reused, for
sports pitch, lawn, or plant
bedding irrigation, or for use in
public toilets.
Shallow attenuation
represents an ideal response
to Schedule 3 of the Flood and
Water Management Act 2010.
This now requires
developments to be authorised
by local Sustainable Drainage
System Approval Bodies
(SABs) before they are granted
planning permission.
The four main pillars of SuDS
are:
• Quantity – the system must
manage the expected
volumes of water
• Quality – water must be 昀椀t to
discharge
• Amenity – rainwater must,
where possible, be usable
• Biodiversity – water should
be used to support
biodiversity
Jack Shuttleworth said:
“Shallow attenuation adds a 昀椀fth
pillar: true sustainability. It’s less
costly, less disruptive, and is
easier and safer to install, with
a smaller carbon footprint than
tank systems.”
Find out more
Forma has CPD programme to
explain shallow attenuation to
ground engineering and design
consultancies, architects, and
government planning teams.
Contact Forma:
jack@forma.uk
01253 224375.
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