HH combined Feb 25 JW - Flipbook - Page 13
Opinion Hayling Herald
Save Our Island
Dave Parham of Save Our Island
WE have now received the Environment Agency’s new proposals for National Flood Risk
Management.
It seems to be a well-considered analysis of the
increased risks for pluvial, fluvial and sea flood
risks, and coastal erosion. Unfortunately, the key
output from the analysis – the new flood and
erosion risk maps – will not be available until
early 2025. So we will have to wait to see the government’s understanding of the risks and consequences and adaptations required.
It is encouraging that there seems to be a realistic acceptance of the likely impacts of climate
change, but there is an unbridged canyon between recognising the risks and the solutions and
funding required to build that bridge.
We need to be assured that clear guidelines are
put in place to reinforce the NPPF and building
regulations, so that development committees and
developers are given clear rules which leave little
room for the manipulation and circumvention
experienced in the past, which was used to drive
through the existing community and infrastructure protection legislation.
This latest Environment Agency Report accepts
that up to 2100, the tide rise will be a minimum
of 1mtr, and recognises it could go as high as 2m.
The existing Environment Agency protection
proposals for Hayling Island have no hard protection barriers, and only a limited soft shingle
barrier at Eastoke. The rest of the coast is not
protected. We know that Coastal Partners have
completed the Hayling Island Coastal Management Strategy which has now been adopted by
Havant Borough Council and will be submitted
to the Environment Agency.
However, funding will require support from the
Environment Agency, Natural England et al. It
will be interesting to see if the new Environment
Agency Plan Maps, when published, recognise
this Coastal Partners’ Plan and commit to provide the necessary financial support.
At the last meeting we had with the Environment Agency at Mengeham Rythe Sailing Club in
August 2024, which followed the serious flooding
in April, the Environment Agency advised that it
would be eight years before a plan to increase the
height of the seawall would be brought forward.
The existing commitment is to rebuild the wall
to its current height.
If the sea level rises by 2m – which is within the
NPPF-mandated life cycle of housing develop-
Flooded Mengeham Rythe Sailing Club
ments of 100 years – there is currently no funded
plan to provide any sustainable infrastructure on
Hayling Island.
It is important to remember that our roads,
power substations, and many of the 17 sewage
pumping stations are also at high risk of inundation.
What follows is Save Our Island’s assessment of
the impact on Hayling Island of the 2024 revised
Environment Agency Forecast on the National
Assessment of Flood and Coastal Erosion Risk in
England.
I have included an IPCC Climate Central model and based it on the worst-case predicted by the
EA. It reflects a 2m tide rise, plus the additional
1mtr tidal surge we experienced in April 2024 as
a result of an atmospheric pressure of 950mb.
n The bimodal wave effect will have an additional impact on the south coast. Historically, we
know that we can expect bimodal waves to be
approximately 2.3m above mean level.
The shingle barrier at Eastoke is currently
maintained at 5.6mtrs AOD (Above Ordnance
Datum). The worst-case scenario at Eastoke will
be as follows:
5.3 tide (2024) = 2.6 AOD
+ 2mtr est to 2100 = 2.0
+ 2024 tide surge = 1.0
+ bimodal actual = 2.3
Total 7.9m AOD
These numbers assume no protection will be in
place in our harbours, where the seawalls are between 2-4m. AOD. It is expected that they will be
over-topped by 1.6 to 3.6mtrs (see Appendix 2.)
It’s interesting to note that the Barratt Homes
unapproved housebuilding plans on Hayling
Island are not based on the new Flood Risk
figures. If the new figures are taken into account,
these proposed developments will be situated on
the only dry land left, and will become islands in
the sea if these ill-considered and unsustainable
plans are allowed.
It is not realistic to assume that Hayling Island
will be protected in the same way as our neighbour Portsmouth has been, at a cost of £300m
and rising. The cost/benefit algorithm of protecting Hayling Island is nowhere near that level,
and funding will be minimal. A reappraisal of
the Island’s monetary value will be necessary to
determine the future of our Island.
Even if Coastal Partners’ plans are accepted by
the Environment Agency as the correct evaluation of the risks, the funding algorithms in use
will not save Hayling Island in its current form.
The flood risks to Hayling Island must be a
primary element of the new Havant Borough
Council Local Plan, including:
n A detailed analysis of the areas at risk;
n An Adaptation Plan for the infrastructure
systems affected;
n A revised Development Plan recognising the
latest risk data.
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