When relationships go wrong
The story of a broken coast

St Bees on the West Coast of
Cumbria
 Cumbria is a diamond
shape
 St Bees is at the
westernmost tip
 It is renowned for its
headland – St Bees
Head

Management
 The location is visited by many field groups
as it has good examples of most types of
hard engineering protection measures
 Promenade, Groynes, Rip rap Rock Armour,
Geo netting and a revetment
 At Sea Mill lane [to the south of the golf
course] there are also gabions.

Which are which?

However the love affair society has
with the coast is a troubled one
 Like most affairs, over the years attitudes
change and what was once a beautiful
untarnished thang is now jaded by over
exposure.
 Before the promenade St Bees was covered
in Sand Dunes …

 The natural ecosystem was on blown sand
 Consolidated by vegetation
 Moving
 Flexible
 Adaptable but also a valuable asset
 Sand and gravel were extracted and the
very good natural defences were
compromised.

The Response
 A variety of different management strategies
were introduced primarily a sea wall with
promenade, 9 groynes at right angles and a
revetment to the South.
 Following a collapse of the railway
embankment to the far south the slope
south of the prom was re-graded, geo-
netting introduced to stabilise the slope and
the later rock armour added at the toe.

Something for Nothing?
 Like most relationships after the initial
commitment some investment of time and
money is needed to keep things sweet.
 Sadly, West Cumbria has suffered from the
same budget cuts as elsewhere and the
hard engineering is beginning to show signs
of a troubled time ahead.

Promenade
 The sea wall has
experienced some
slight movement and in
places the mastic
between the block has
been stripped out by
the sea.

 Originally a flat surface
stones lie in the
remaining hollow
No expansion
filling

 In places the wall is inadequate and has been
overtopped with the beach material re-deposited
on the surface

 The sea wall no longer works as a barrier but as
an extension to the beach. The retaining blocks
behind are now battered.

Further up the sea wall…
 A lifeboat ramp
has been built. An
immoveable
barrier which
reflects the waves
energy, scouring
out the beach and
transferring the
material off shore.

Groynes
 Generally these are in
a bad state of repair
despite some attempt
at maintenance.
 In some places the
buckle under the sheer
weight of stones.
 In others sections are
missing or fixings
badly corroded.

You can see some of
the new sections –
sourced from tropical
hard wood?
 And in other places
holes right through
But what is the alternative?
Plastic replacements used re-cycled bale wrap but would not
biodegrade when they eventually come loose.

North of the promenade
 At the end of the sea wall a bridge passes
over Rottington Beck and is secured on a
block of unprotected concrete.
 The energy transferred northwards attacks
the mouth of the beck undermining the
foundations

 Nature continues to work around the man made
obstacles, the beach re-grades and the mouth of
the beck cuts out to sea.

 The lined channel accelerates heavily
sedimented material towards the coast
To the sea

 Despite all this
management slips and
slides still occur on
newly deposited
material.

Accretion and deposition
 Material moved in
shore up the mouth
gradually build up on
the river bank
 At the mouth a small
delta appears due to
too much material
 A spur growth across
the mouth

In Conclusion
 A natural system was  Natural systems still
managed using a hard work hard to overcome
engineering solution. the human intervention
 Maintenance of the  Micro forms of some of
this facility has been the landforms appear
poor and in winter it especially at the
struggles to keep fluvial / coast interface
material in check.

The future?
 The adoption of soft engineering solutions
are now more widespread
 Further south where the cliff material is
unconsolidated glacial clay a ‘do nothing’
approach has been utilised effectively.
 Imaginative new approaches are still being
developed – recycled plastic shuttering to
line a different beck's mouth.

Who knows, our
rocky relationship
may stand the test of
time …