Introduction to your Fieldwork Focus –t
Mudeford Spit also called Mudeford Sandbank is
a depositional feature. There are no permanent
on the sandbank
to settlements
do!
Long groynes, they
were built in 1939,
this was to trap
sediment, and stop
long shore drift.
Hengistbury
head
Head is 1km long, 35
meters tall, mostly
composed with
sedimentary rocks
Hengistbury head
bournemouth, 9 min drive, 44 min
walk
In the county of
Dorset, the county
neighbouring Dorset
is Hampshire
Wiltshire and
Somerset.
london
important place in the uk, London.
Hengistbury
head
From London 1hr 55 mins drive
4hr 14 mins bus
2hr 28 mins train
Jack barnes
+
These waves come all the way
from Brazil
Landforms and cb
Geology of cb
Land use of cb
Mudeford spit was sold the Bournemouth council in 1935. The
spit was formed by sand and shingle brought around
heingusbury head bye longshore drift and the waves push to
shore from the East, the waves come from Brazil and this is
called a fetch. Constructive waves break on the shore and
deposit material, building up beaches, they occur when the
weather is calm and they are less powerful than destructive
waves.
At heingustbury head the rock includes clay and aslo sand, the
strata include hard rock and soft rock and also the
The land there is used for beach huts, there are many along the
spit. Many people come down for a weekend or a few days and
rent out the beach huts.
PART 2 – WHAT IS CB LIKE?
Part 3
Hard engineering:
•
Gabions at Double Dykes and the base of HH at Warren Hill- The gabion are rocks in the cage
that protect the double dyke at the base of hengustbury head. This protects the base of hengustbury
head from erosion. From 2005 to 2008 Poole Bay was replenished with 1.8 million cubic metres of
beach material, drawing wire from some surfers and beach lovers owing to the increase in sharp
stones on Southbourne beach. Prevent Hengistbury Head becoming Hengistbury Island.
•
Old sea wall running from base of HH onto Mudeford Spit in front of the beach huts- The sea
was is good and very sustainable as it protects the beach huts from the sea, This is a good method of
protection because the beach huts are very important and they attract a lot of tourist as people
come down on holiday and rent the beach huts. The beach huts are very high land value so they
want to protect the beach huts.
•
Rock groynes along Solent beach at HH onto MS- The rock groynes is good protection, this
prevents longshore drift so Hengistbury head and Mudeford spit have more sand and more of the
beach for tourists. This is sustainable has this has reduced the amount of longshore drift. Also the
rock groynes is more natural and looks good as it looks natural. Jack barnes
•
Long Groyne – at the beach end of HH- The long groyne is really effective at Hengistbury
head as it reduces a lot of longshore drift, it is make the beach bigger and reducing the loss of sand
by a huge amount.
Soft Engineering:
•
Beach replenishment along Bournemouth and up to Double Dykes in 2006 and 2008 and top
up in 2014- The method used for beach replenishment involves building a temporary 50 cm
diameter pipeline from the beach to a dredger, which moored about 300 meters off the shore. The
dredger pumps up the sand as a slurry from the sea bead and this is then transported to the beach
through the pipeline. Beach replieshment is sustainable but it is expensive as you have to keep
putting sand on the beach.
•
Sand dune development- This type of management protects the coastline, it is weak but not
very sustainable however, the sand dunes look good for the environment. The sand dunes reduces
erosion.
Groyne- the groyne reduces the long shore drift keeping the beach sediment on the beach, reduces
coastal erosion. Prevents the movement of beach material along the coast by longshore drift.Allows
the build-up of a beach. Beaches are a natural defence against erosion and an attraction for tourists.
Gabbions- Gabions are quite simply bundles of rocks in a metal mesh. They’re placed at the base of a
cliff in an attempt to reduce the impact of waves on the cliff and prevent the cliff from being
undercut. They’re not particularly effective and they’re quite unsightly but they are cheap.
Sea wall- A wall built on the edge of the coastline. Protects the base of cliffs, land and buildings
against erosion. Can prevent coastal flooding in some areas.
Rock amour- Large boulders are piled up on the beach. Absorb the energy of waves. Allows the
build-up of a beach.
Riprap- Riprap are just rocks and stones that have been put against the base of a cliff. They’re similar
to gabions in their purpose but they aren’t bound together in a mesh. This makes them look slightly
more appealing as they blend into the environment better however the rocks are susceptible to
being moved by the sea.
Sea Walls- These are the most obvious defensive methods. Sea walls are exactly that. Giant walls
that span entire coastlines and attempt to reduce erosion and prevent flooding in the process.
They’re big, ugly and very expensive requiring constant maintenance so that they don’t fail. They
also produce a strong backwash in waves which undercuts the sea wall making their long term
sustainability questionable. Traditionally, sea walls are large flat walls however more modern sea
walls have a curved structure that reflects waves back into incoming waves, breaking them up and
further reducing erosion.
Jack barnes
Marshland Creation- Marshland can be used to break up the waves and reduce their speed, reducing
the wave’s erosive power. The marshlands also limit the area which waves can reach preventing
flooding. The marshlands can be created by encouraging the growth of marshland vegetation such as
glassworts.
Beach Nourishment- This is where sand and shingle are added to a beach in order to make it wider.
This increases the distance a wave has to travel to reach the cliffs and so the wave will lose more
energy and have less erosive power when it reaches the cliffs. The sand and shingle has to be
obtained from elsewhere and is normally obtained from dredging.
Land Management- Land management is often used to help protect and rebuild dunes. Sand dunes
act as a good barrier against coastal flooding and erosion and they can be exploited as a natural
defence against the sea. In order to do so though, the dunes must be left relatively undisturbed so
boardwalks are constructed and sections of sand dune systems are marked as out of bounds to the
general public in order to reduce the erosion of the dunes by humans. This land management is
discussed in more detail
Sand dunes- This is a soft engineering strategy, it consists of planting marram grass to catch the
sediment creating dunes, which are a natural sea defence. This is a sustainable defence as it is
economically effective and doesn’t
1- Has long groyne successfully widened Solent beach.
I predict that Solent beach will get wider due to the long groyne, it will reduce the long shore
drift and also it reduces the amount of sand that’s goes into the sea, the longshore drift
traps the sediment.
2- Has the gabion revetment scheme prevented Hengistbury Head from becoming an island?
Yes as it still is a headland, it has stopped Hengistbury head from becoming an island as the
gabions have reduced
3- 3- How sustainable are the coastal defences?
Socially the coastal defence is a problem, people disagree with the
Jack Barnes
Field sketch
Draw the area around
you accurately.
This links to question as
has the sketch shows
that the beach
widened, weather it
has become a headland
and that has the long
groyne worked?
Photographs
Take a picture of the
area surrounding you
Secondary data
Get data from other
people.
This links to the key
question as it shows
have the defences
prevented Hengistbury
head of becoming a
headland. Have the
coastal defences
worked?
This links to the key
question as it helps me
sort out my conclusion
for each question.
I would expect to see
that the west side of
the long groyne would
be long and the east
side would be smaller,
The long groyne has
prevented LSD where
sediment is moving
from west to east.
In the photos I would
expect to see a gradual
hill. I also would see
shorted groyne drop on
the west as the
sediment has built up.
The drawing may not
be accurate. Take a
picture in case for back
up.
I would expect to see
similar data as we had
the same groyne, but
the bipolar surveys
might be different.
Not have similar data.
Do groyne drops and
beach profiles in the
same place and the
same groyne.
The photos don’t look
the same as real life.
Take pictures from
different angles.
Fieldwork
technique
Description
Explanation
Expected outcomes
Problems and solutions
Bipolar
surveys
Used our judgment
give each criteria a
score between -3 and
5. We used two
ranging poles to
measure the angle on
the slope at the two
break points. We
measured the slope
with a clinometer we
could read it if the
slope was – or +. We
measured 2 meters
from the shoreline,
also we can see if the
beach is building up in
sediment.
I used a compass so I
could measure and
see what side of the
groyne is West and
East. Used a metre
ruler to measure the
highest point of the
groyne to the
sediment on each side
of the groyne
We reviewed the data
and gave a mark from
3 to -3
This links to question 1
by completing the beach
profiles, this means that
I will be able to see the
changes along the
coastline. As we done
this we can see if the
long groyne has reduced
long shore drift
By completing the
beach profiles it links
to the key question
which is that the long
groyne has
successfully made
Solent beach wider. I
will be able to see
the differences
between the sides of
the Solent beach.
You will have to meausrue the same point
the day so you can see the variation in the
waves.
You need to make sure the ranging poles a
equal and their not sinking into the sand
So you can get a fair results
For the beach profile.
Make sure that the end of the pole the me
bit is submerged into the ground
Uses error while taking measurements with
the clinometer.
Walk in a straight line with the compass.
This links to the key
question 1, by doing the
groyne drop I will be
able to see the height of
the sediment on each
side of the groyne.
As I went further up
the beach you will
see the difference as
there would be more
sediment either side
of the groyne, the
sediment will build
up.
The measurements have to be taken at
the same point at
The groyne. Measure how
Far u measure up the groyne. Make sur
the ruler is held straight and make sure
it’s not sinking into the sand. Have the
ruler resting on the sand.
This links to question 1
as is shows the
economic, social and the
environmental
sustainability of each
coastal defence.
I would expect to see
soft engineering such
as sand dunes which
score well with
environmental
sustainability. They
have a high aesthetic
value. They are made
up from materials
from the environmen
Get notes, pictures, sketches to support
Your evidence. Get a range pole to
Complete the bi polar in order to make sur
you reduce bias. When the survey
Multiplies sites it is hard to select a criteria
For a scoring system. We covered a lot wid
range of criteria and gave a detailed
description so the evidence was accurate.
Groyne
Drop
Bipolar
Survey