Chapter 9: Road drainage and the water environment

7 PPS25 Sequential and Exception Test
In this section, the suitability of the scheme in relation to the requirements of
PPS25 has been considered.
The widening of the A14 slip roads and proposals for the bridleway crossings will
require embankments (approach ramps) which encroach into the Flood Zone 3a
as defined by PPS25. The proposed development is classified as essential
transport infrastructure and therefore is only permitted in Zone 3a if a FRA and
the Sequential Test and Exception Test are completed.
7.1 The Sequential Test
The Sequential Test should be applied to demonstrate that there are no
alternative sites within the area with a lower probability of flooding that could be
used for the development. In this case, the A14 crosses the River Avon and the
existing junction is close to the watercourse, it is not possible to relocate the
development outside of the floodplain.
Since the development is regarded as Essential Infrastructure and falls within
Flood Zone 3a (refer to to Table 3) the Exception Test will need to be performed.
7.2 The Exception Test
For the Exception Test to be passed:
a) It must be demonstrated that the development provides wider sustainability
benefits to the community that outweigh flood risk, informed by the SFRA where
one has been prepared.
Response:
There are known, high profile, congestion and safety problems with the M1 /
A14 junction. The improvements to the junction will therefore reduce the
stress associated with travelling across Junction 19, increase safety for
vehicle drivers and reduce travel times.
b) The development must be on developable previously developed land or, if it is
not on previously developed land, that there are no reasonable alternative sites
on developable previously developed land.
Response:
Due to the existing location of Junction 19 and the River Avon, it is not
possible to locate the development elsewhere.
c) A FRA must demonstrate that the development will be safe, without increasing
flood risk elsewhere, and, where possible, will reduce flood risk overall.
Response:
In this case the proposals include floodplain compensation storage for the
areas of the floodplain required for embankments and bridge approach
ramps. The existing drainage alongside the M1 and existing carriageway
drainage will be maintained and improved in accordance with consultation
with the EA.
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