7. Are you convinced that Rowen Spit will not continue to provide protection from sea level rise as
per SMP1? What is your scientific basis for this change? How much investment was done in
drawing up these plans on the accretion increasing the height and therefore the natural defence
properties of the whole length of the Spit?
Rowen Spit (PU11.4) is the length of spit which is to the north of the newly refurbished estuary
defences and as such does not provide a direct defence to Fairbourne village. We know that the
shingle bank is suffering from starvation because of the depletion experienced at Friog and that
there is no net accretion in the system. We know that on 3 January 2014 the sea overtopped the
shingle bank and the overtopping wall – this will occur more frequently as sea levels rise as a
result of climate change.
The strategic monitoring which has been recording measurement along Fairbourne frontage
since 1992 does show that some accretion is occurring along the Rowan Spit frontage. The
accretion however is localised and as no new shingle material is being fed into the overall system
the level of protection is diminishing over time.
22. Has the impact of silting up of the estuary and the benefits of dredging been explored?
Dredging can have limited benefits when dealing with rivers by providing extra capacity
regarding flow and storage because of the finite volume of water being considered. The sea has,
in effect, an infinite volume and therefore, dredging would have no benefit with regard to flood
risk to Fairbourne.
23. What is saved by allowing Fairbourne to flood in terms of ongoing maintenance costs? Does it
protect Barmouth and Dolgellau?
Further details of current maintenance will be provided in due course. The sustainability of
defences at Fairbourne are not however determined by the on-going maintenance requirement
but rather by the need, in the future, for major capital improvements to maintain standards of
defence in face of sea level rise and climate change. Certainly there is no suggestion that a
decision not to defend Fairbourne would be to allow better defence at Barmouth or Dolgellau.
There is no consideration of direct flood risk benefit to either Barmouth or Dolgellau in
considering Fairbourne’s future. Any decisions made as to flood risk either from the sea or
fluvially in Fairbourne will be based on the conditions and the sustainability of the existing
defences. There is no long term significant maintenance savings by not carrying out annual
maintenance. As far as Natural Resources Wales are concerned there is currently no intention to
curtail the maintenance programme. In fact we are currently working with landowners to
improve localised drainage at a known problem area behind Penrhyn Drive South.
42. Anecdotal evidence indicates significant silting up of the Mawddach Estuary. Is this being
monitored? Has the impact of the new Barmouth seawall been assessed?
The Mawddach Estuary is referred to as a sink because material is accumulating in the estuary
and has been doing so since the last ice age 14,000 years ago. This accumulation of material
also created the land Fairbourne is founded on today. This process will continue until an
equilibrium state is achieved and the process is reversed and material is lost from the estuary. It
is impossible to say when or indeed if an equilibrium state will ever be achieved because of the
effects of climate change.
Gwynedd Council do not monitor the siltation in the Mawddach Estuary. However there is a data
set of aerial photographs which can indicate the changes which have occurred over the years.
Aerial surveying using LiDAR is being used more frequently these days and the latest was
undertaken by The Wales Coastal Monitoring Centre in April 2014.
I assume that the new sea wall referred to is the causeway constructed between the mainland
and Ynys y Brawd in the early 1970’s to close the north channel into the estuary. One of the main
reasons for closing the channel was public safety because of numerous drowning incidents but
there is also evidence to suggest that the channel was closing naturally and the causeway just
accelerated the process.
The silting of the estuary is a natural process with each tide carrying a load of suspended
sediment into the estuary of which a small percentage settles out and is deposited on the
sea/river bed. which has accumulated to a depth over 50m by today, a rate of less than 5mm per
annum. There is no evidence to indicate that the causeway has had a detrimental effect on the
siltation of the estuary. The causeway is only the latest episode in a catalogue of anthropogenic
interventions which have changed the characteristics of the estuary. The catalogue includes:
• Fixing the estuary mouth by Trwyn y Gwaith
• Constructing the railway viaduct in the 1860’s
• Land reclamation along the length of the estuary including where Fairbourne is now
• Constructing the causeway in early 1970’s
• The placing of reno mattresses under the railway viaduct in the 1980’s
There is no evidence to link the current flood risk facing Fairbourne with estuary siltation and the
construction of the causeway.
44. What program of Storm Drain Maintenance is intended for the village? Will NRW publish a map
of adopted and non-adopted drainage ditches and water courses and how will any lack of
maintenance on non-adopted drainage ditches impact on the risk of flooding?
Fairbourne is within the Internal Drainage District (IDD), so we have permissive power on all
watercourses, not just those which have been nominally “adopted” so a map of adopted
watercourses is not totally relevant.
We will carry out channel maintenance on the Main River system leading down to the tidal doors
in December/January together with the non-main river ditches that we normally clear.
We will monitor the system for blockages and ensure that the grids are kept clear on a regular
basis.
There is no scaling down of maintenance planned, in fact with the new scheme there will
probably be an increase in maintenance. This is the first year, so we don’t have experience of
what is required yet.
There is certainly no cut back which might increase flood risk to the village.
A project to review IDDs may change the way adopted ditch maintenance is handled, but Main
River works are unlikely to change.
45. Will pebbles and stones displaced in the storms be returned to the appropriate areas on the
beach and shingle bank?
The shingle bank referred to does not belong to Natural Resources Wales (NRW) it is Crown
Estate Land mostly bordering land owned by Gwynedd Council on which sits the Concrete Sea
Wall that NRW maintains. The rock armour at Friog Corner is to sustain the Concrete Sea Wall.
The question of shingle at Friog corner which we answered earlier under Q52 of the FAQs still
stands as Gwynedd Council’s beach monitoring and NRW’s Friog Corner study will identify
options which may include shingle nourishment which would be considered for further
assessment. NRW would be involved in any shingle management essential to maintain the
concrete sea wall and Flood risk in the community, but not clearing up of shingle washed over
onto the path/road walking unless a direct flood risk management issue has been identified.
NRW thinks that debris was cleared during a previous storm by Gwynedd Council; perhaps their
maritime team?
46. There is significant concern from the Community regarding 2 areas in the Rowan Embankment
where the shingle has been washed out opposite Penhryn Drive South. This is leaving the
Embankment in both areas vulnerable to over-topping during high tides and storms. Are the
relevant agencies aware of this and what plans do they have to rectify the situation?
Natural Resources Wales are aware of the concerns however the integrity of the sea wall is not
compromised and the shingle bank has been profiled naturally by sea wave action. We will
continue to monitor the situation together with Gwynedd Council, who have already undertaken
beach profile studies and this is also covered within the contents of the brief for NRW’s
proposed Study of Friog Corner. There is no evidence as yet that this will exasperate the
splashover.
The local action undertaken on the access has inevitably cut off the splashover flood route to
the properties affected during the January storm. An improved flood warning service will also
provide a more specific warning to residents along the frontage.
47. Have the relevant agencies given consideration to using movable interlocking concrete barriers,
similar to temporary motorway interlocking central reservations, that can be placed at risk areas
during winter and removed when not needed?
Is this referring to the provision of a secondary defence behind the existing sea defence? If so,
then we would not currently consider this option as it may accumulate more water behind the
defence rather than let it seep away. This is something that Natural Resources Wales could
discuss further with the Fairbourne Facing Change Action Group.
51. It is understood that spoil from weir clearing and from the bridge over Afon Wnion in Dollgellau
has been used for a number of years to build up defences along Afon Mawddach on both sides
at Bontddu and Penmaenpool. Has this work been authorised and is the impact of flows during
high rainfall events monitored?
Gravel from Pont Fawr Dolgellau was taken to the Ynys floodbank at Penmaenpool some fifteen
years ago and is not to be confused with material which went to many locations on the
floodplain as part of the recent Gelligemlyn road improvement scheme. The gravels were
utilised behind the embankment to strengthen identified weak sections maintainable by our
then predecessors Environment Agency Wales which was fully assessed. No further gravels have
been used for this purpose and have since been disposed of at various other locations to include
Friog corner.The material recently imported from the road scheme has been assessed to have
no detriment to Fairbourne.
52. Will the relevant agencies consider/commit to the replacement of pebbles and shingle at Friog
corner and surround?
This decision will come as a result of both Gwynedd’s monitoring process and the outputs from
NRW’s Friog study.
58. SMP2 provides the following definition:
“Sustainability is a concept, which deals with mankind’s impact, through development, on the environment.
Sustainable development is ‘development which meets the needs of the present without
compromising the ability of future generations to meet their own needs’ (Brundtland, 1987). It
should also take account, for example, of the long-term demands for non-renewable materials.”
Can you explain how preserving Fairbourne for the next 100 years will compromise the ability of
future generations to meet their own needs?
In answer to question 55 we have hopefully addressed the issue raised by this question in setting
out the thinking behind the conclusions of the SMP in relation to sustainability.
It is acknowledged that, as stated in the Defra Guidance that ‘sustainability’ can mean different
things depending upon the individual viewpoint; it is not necessarily the same for conservation
bodies, the national treasury, or local residents within a coastal settlement. What is required is
consideration of the conflicting pressures on the coast and constraints upon its management, to
seek to provide an optimised plan, one which provides ‘balanced sustainability’ i.e. it needs to
consider people, nature, historic and socio-economic realities.”
If, however, we do not address the issue raised by the SMP now and understand and examine
how we address the issues, then we consider that we are merely handing on the problem to
future generations, with far less time and opportunity to deal with the important issues that have
been raised.
61. In low‐lying towns and villages such as Jaywick in Essex that are defended by a high sea wall,
pumps have been successful in clearing the water and preventing it from coming back. Could we
not have water‐powered pumps from a waterfall and tidal movement to push water back out to
sea when there is heavy rainfall? Uplands can also be better managed.
There are obviously many areas around the coast where there is land and villages at risk from
flooding. In each of the SMPs this risk has been considered and in some cases recommendations
have been made for a need for change. As identified in the question Essex is an area where there
is substantial risk and this has been considered in the respective SMP. In some areas in Essex
managed realignment has already been carried out and further cases are still under
consideration in the longer term.
Much of Jaywick, itself, tends to be built over slightly higher ground, although vulnerable both to
erosion and flooding on extreme water levels. In 1953 the main village was not inundated. It
was, however, cut off for several days due to flooding around the back of the village severing the
main road to the village. There was also a major failure of the sea wall, although this did not
result in direct flooding but the sea wall was overtopped by wave action.
During the 1970s and 80s, the main concern was that beach scour was undermining the main
sea defences. The shore had been reduced to its underlying clay. Major works were undertaken
to restore the beach and significant investment followed in maintain these beach levels.
Notwithstanding this, serious consideration is being given to the long term sustainability of
management in the area. It is understood that over the longer term there may be need for
further adaptation.
We are unsure of where precisely pumps have been installed as suggested by the question.
However, possibly this is in relation to areas to the back of the village rather than to the village
itself as, as previously mentioned the village is generally on slightly higher ground. It is possible
that pumps have been used to remove water after a severe flood event.
In the case of Fairbourne the concern is that ground water levels will cause a problem rather
than just flows from the rivers or flooding due to overtopping. To address this overall problem
would require a different level of management which would need to be increased progressively
as sea level rises further. Pumping would need to be in effect continuous to reduce ground
water to an acceptable level. This issue of ground water is one of the areas being monitored and
from the information collected how this might be managed will form part of the overall
management.
Pumping would obviously need a reliable source of power and certainly with developing
technology, it seems unlikely that this could be won from tidal generation. Similarly, obtaining
such a power source from water falls is unlikely to be sufficient. This whole issue could be
reviewed but seems unlikely to provide a solution. This is being realistic, rather than negative, as
the project has to maintain an open approach to all ideas.
On the final point, upland management tends to be most beneficial where there is an
opportunity to provide storage, either as some form of reservoir or through land management.
The project will review what investigations have been undertaken already as part of the study
looking at management of flows through the area.
68. What the Council believes is what matters – can we engage a legal environmental champion to
take our concerns forward?
We can certainly investigate the cost of doing this, however, we need to be mindful of our
limited budget and ensure that what we spend our money on returns a fair investment for the
project and community alike.
84. Rainfall recently hasn’t been a lot heavier than other years based on 20 years of historic local
data, so what does the future hold? What is different?
The work reported by UK Climate change programme (UK CP09) makes projections of change in
rainfall intensity. UK Climate projections indicate that winter high intensity rainfall could
typically increase by:
0 to 10% over the period 2010 to 2039
10% to 20% over the period 2040 to 2069
30% to 40% over the period 2070 to 2089
85. The sluice gates aren’t big enough to handle the amount of water off the mountains in
December. Is there a negligence issue? Recent observations of higher retained water levels by
railway, backing‐up of water behind gates and older, earlier gates working better.
If it’s regarding the penstock control structure upstream of the railway at the point where flows
are diverted into the new channel then this performed well during the December flooding by all
accounts but there are a few issues here that will need to be directly observed during any repeat
of higher rainfall events. This is a new flood scheme and we will be monitoring its performance
and this will involve operatives visiting this site on the higher scale events.
We’ve had positive comments from some residents that despite the significant rainfall of
December there hasn’t been a major fluvial flooding issue in the village.
88. Why can’t we simply raise the height of our existing sea defences? How would Holland deal with
this problem? If they can manage the problem, why can’t we?
The SMP poses this exact challenge. It is always of course possible to build higher defences,
restore beach levels, deal with the flooding due to the rivers and pump to reduce ground water.
There remains the problem that whatever is done, there remains the risk that defence measures
fail or are exceeded. This is a problem that will become worse with the effects of climate change.
At present Fairbourne is protected to a good standard of defence and emergency planning has
been put in place to address the risk that defences are overwhelmed. By moving down the
course of action suggested in the question there is ever increasing dependence of defences. In
the Netherlands this is the situation that they are in. They are, however, looking in some places
at alternative solutions.
89. Has Fairbourne had a T100 level in recent records? What about in 1998? If we had had a T100
level and not had a breach, then why the current concerns?
No there has not been a recorded T100 event because our records do not go back that far. The
1998 event was estimated to be around a 1:2 year event based solely on water levels. The event
in 2014 was, based solely on water levels, around a T20 extreme. The waves associated with this
event possibly raise this to a higher return period.
With sea level rise the typical event that might be considered now as a T100 event is likely to
occur on a far more frequent basis. Typically with 0.5m sea level rise, the extreme water level
that might on average occur every 100 year now, might occur every couple of years.
90. Why wasn’t the defence raised during January 2014 repairs? Would it currently do a proper job
in defending the community?
We presume this question relates to repairs at Friog Corner in January 2014. The concrete wall
at Friog Corner is given as meeting the 1 in 200 year return period event standard and meets the
standard of protection design criteria for present day coastal schemes as agreed by Welsh
Government. The repairs at the Corner in January 2014 reinstated the crest to its design level.
The repair works were undertaken in accordance with the SMP2. It is very unlikely that higher
defences would have got planning approval.
