Core Strategy Preferred Options document - Amazon Web Services

Strategies, Activities and Actions – Environmental Issues
ENV3 Flood Risk – Preferred Option
We will seek to direct development away from areas at risk of flooding
by applying the sequential test and, where necessary, the exceptions
test, as per PPS25. The vast majority of development will be
accommodated within Flood Zone 1.
We will continue to work with the Environment Agency, scrutinising
and monitoring the impact of the technical advice on flood risk
provided by the Agency. We will continue working with the
Environment Agency to maintain sustainable flood defences in order
to reduce the risk of flooding.
ENV3 – Alternative Options
Option Why is it not preferred?
Relocate existing development in
Great Wakering and other
residential areas away from
areas of flood risk.
The relocation will have a
negative impact on community
cohesion.
ENV4 Sustainable Drainage Systems (SUDS) – Preferred Option
All large scale development will be required to incorporate runoff
control via SUDS to ensure runoff and infiltration rates do not increase
the likelihood of flooding.
SUDS will be required in all new development sites, unless there is
evidence showing the system is not viable on the site. In such cases
developers will be required to implement alterative forms of drainage.
ENV4 – Alternative Options
Option Why is it not preferred?
Sustainable Drainage Systems
(SUDS) will be encouraged on all
development sites.
There is a possibility such an
approach will not ensure
environmental quality or reduce
the risk of flooding.
57
How these SUDS
techniques work
(continued):
Swales and basins –
“Swales are grassed
depressions which
lead surface water
overland from the
drained surface to a
storage or discharge
system, typically using
the green space of a
roadside margin.”
Infiltration trenches
and filter drains – “An
infiltration trench is a
shallow, excavated
trench that has been
filled with stone to
create an underground
reservoir.”
Ponds and wetlands –
“Ponds or wetlands
can be designed to
accommodate
considerable variations
in water levels during
storms, thereby
enhancing floodstorage
capacity. Only
specially constructed
wetlands should be
used to treat surface
water – the use of
existing, natural
wetlands is unlikely to
be acceptable.”