The purpose of this investigation is to test the following research question:
“What management is there at Freshwater Bay and how effective is it?”
Fundamentally this means that I am going to study the area of Freshwater Bay then test and examine what positive or negative effects the management has on the area.
My research and findings are going to test the question to find an answer. In order for me to answer this question I am going to break it down into two main sections:
* In what way does management of the bay change it from east to west?
In this study I am going to examine how the management schemes are effecting the beach, and in what ways it its doing this.
* What is the main land use behind the bay and how is management protecting it?
In this study I am going to examine the land use at Freshwater Bay and see what the management is being used to protect.
Location of the area:
The Isle of Wight is and island 380kmï¿½, and is situated off the southern coast of England in the English Channel. The island itself is represented as one of the counties of England and has a population of 111,300 people.
Freshwater Bay is situated on the South East coast of the Isle of Wight. The A3055 is the main road that runs along the west cliff top and down through the Freshwater area.
The information that I require for my investigation is shown in the tables I1 and I2 below.
For my first section I am going to use collection techniques such as:
* Photographic evidence
* Field Sketches
* Quadrat sampling
* Transect mapping
* Cliff recession mapping
These techniques are simple to perform and give clear evidence in answering specific questions.
For my second section I am going to use collection techniques such as:
* Photographic evidence
* Field sketches
* Land use mapping
These too are simple to perform and effective in giving clear evidence in answering specific questions.
I have also done some additional research in the forms of:
* Geology mapping
* Wind rose diagrams
* Wave count
These methods allow me to make conclusions by referring to actual evidence.
To start my survey I had chosen six sites, (shown in MP4), evenly spaced across the bay. The bay seems to be divided up by sea walls, groynes and rip-rap on one side of the bay and on the other side there is no evidence of management. This is why I took three samples from both sides of the bay.
Sampling Regime for Data Collection
I have chosen the following sampling regimes:
* Place pantometer exactly at sea wall/cliff face
* Measure 1m up to water front
* Measure angle every meter
* Plot collected data on graph
* Place every 5 meter mark
* Sample 10 sediment particles randomly
* Measure length, width and height
* Average all three for each particle and then for collection of particles
* Plot collected data on graph
These method tables show how I plan to test and examine my investigation
Primary Data – Figure I1
Photos taken at points around application site
Exact image of site
Camera limitations and skill of photographer
Acquire skilled photographer, use technical camera
Sketches drawn at application site
Exact evidence of site
Skill of sketcher and knowledge
Background reading into field sketches and practice
Random sediment samples taken and measured
Smaller area to work in, easily analysed
Sampling not entirely random
More particles measured
Beach profile measured with pantometer
Beach clearly evaluated from cross section point of view
Tide (high or low), skill of investigator
Practice and speed, investigate times of tides
Wave frequency calculated
Clear background knowledge of wave frequency can be provided
Wind and timing, skill of investigator
More than one test with average concluded.
Land use recorded onto map of site
Land use can be clearly seen and why management is needed
May change over course of investigation
Research into change via secondary reading
Secondary Data – Figure I2
Cliff recession mapping
Dated maps provided from council drawn together for recession imaging
Recession clear and precise from maps
Maps may be difficult to obtain
Collect in advance
Geology of site mapped using textbooks
Clear imaging of the geology in the area
Resource may be dated and geology could have changed
Research date of resource
Wind Rose diagram
Wind Rose diagram drawn using dated wind data
Once collated with other mapping erosion may be clear
Data and scale may be incorrect
Check data and make scale as clear as possible
As part of my data collection I took the opportunity to take a wave count to gain knowledge of the bay I was working in to be able to use it in reference.
My sampling regime for this test was:
Measure: Every wave that hits a selected point from where I am standing, in this case it was an exposed rock 20m from shore line
Display: Write data collected in qualitative form
The sites I chose to perform this test were at 1,3 and 5. I chose these sites because:
* Site 1 is at sea wall, outside the Royal Albion Hotel – high management
* Site 3 is at area of newly built apartments – small sea wall but beach not managed
* Site 5 is at eastern end of cliff – no management
Table of findings:
Amount of waves in 5 minutes
My field sketches have been drawn to show primary research of images in the area of my investigation.
> Housing development that has recently been built.
> Lies 6 meters from edge of cliff, which is made of very loose clay and slumping heavily, problem for the house.
> Also large recession in the area (see DR 16-18)
> 2 small sea walls put in place but not very effective, due to large sediment build up at bottom of cliff.
> Boathouse, not in use whilst performing study.
> Large build up of sediment either side of ramp and against sea wall in place.
> Sing of effectiveness due to no trace of sediment on way to ramp or ramp
> Royal Albion Hotel, been in area since 1898, major source of income
> Since 1898 been protected (see DR18), presently protected by sea wall and riprap
> Very effective as no trace of sediment near hotel
> Facing cliff in western half of bay.
> No management, left to develop naturally. DR16-18 and DR19 show evidence of dramatic erosion in the area, also most open area to erosion by wind.
> Large amount of chalk on beach from slumping and possible storm attacks.
> Road built in 1830 now non-existent due to this.
> 2 stacks formed in area of bay, sign of heavy erosion in area. At low tide level a wave cut platform can be seen showing more signs of erosion.
Studying this evidence it is clear that where there is management and beach security there is very little to no erosion or recession, but where there is neglect and lasse fair techniques there is heavy erosion. I had predicted on this finding, and it appears the management schemes in the area are doing their job to a high standard.
Photographs – taken from a Medina Valley sub-site
Shows where the management area stops. Housing development shown to be very close to cliff and how cliff is slumping. Other management techniques are shown, litterbins can be seen, shows high levels of care for area. Sea wall can be seen, 1 foot above label of pavement and holds back sediment washed up by sea effectively. Second set of housing can be seen, appear very close to edge of cliff, area of very little or no management, chance of housing disappearing in near future. Photo clear in showing effectiveness of the management in the bay area. Area of bay with little management being rapidly eroded, side with management very little signs of erosion and no erosion at all.
Shows eastern cliff face and lack of management. Shows where old road used to be and how much has been eroded. 2 stacks on cliff point there due to heavy erosion taking away large area of cliff. Face has very sheer drop from top, clear indication of erosion. Sub-aerial erosion occurring, removal of sediment, wind blows for many days at this face and brings rain onto this area. When at low temperature the rain will do a lot of erosion damage with expansion of cracks.
Shows clear view of western side facing bay, clear that Royal Albion Hotel close to edge of sea front. Sea wall present here with small amount of riprap so no water makes it to hotel. Photo also shows how effective the groynes are in trapping the sediment. There are large amounts of sediment shown in large piles up on the beach being trapped by sea wall. This provides extension to sea wall and in storm surges will act as barrier to large destructive waves.
After studying my beach profiles I found that where defences and management have been used (DR9-11) the beach is much steeper and shorter. But studying (DR12-14) where the beach has a lesser gradient and is shorter in length.
This proves again that the defences are very effective, because by creating the steep, short beach, a sea wall is made from the sediment. This will stop the powerful destructive waves getting near the built up areas.
By studying the first profile I can see it is of similar shape to profiles 5 and 6. This can be considered an anomaly due to it being the profiles just before the groyne defences are put in into place. This may be the cause for the lesser gradient and also the fine sediment.
When examining the beach profiles with no defence (DR12- 14) I can see that the gradual gradient and the sediment would be easily disturbed by any destructive wave or storm surge entering the bay. As shown in DR4 there is a lot of erosion near the area, including a lot of fallen chalk.
Another indication that the defences are effective is the sediment size. In figures DR10 and DR11 the sediment size is much larger than DR12- 14 due to the groynes, as the groynes are more effective at trapping large constructive material.
Cliff Recession Mapping
The cliff recession mapping that I examined has proven to be the most helpful source of secondary data that I have developed. This is due to the fact it shows how effective the defences and management has been over the past 100 years.
1898 – DR16
Studying the map shows:
The beach area was much larger, extending right out into the bay. This occurred all the way around the bay. Land use in area was much more primitive than today, with only two farms and four houses. Majority of area is the field network surrounding the bay. Another feature is that the Royal Albion Hotel had been constructed at this time and is one of the only sources of income in the area. This too is the case today. Groyne management is in use at this time and is focused on the western cliff, not in place today as cliff had been eroded further back. Main focus of erosion is on eastern cliff, reduced by 440 feet aprox. Referring to wind rose diagram (DR19) shows that majority of wind blowing in direction of east cliff in the bay.
1960 – DR17
Map shows similar features and structure to bay in 1898, now only two small groynes and sea wall managing bay outside of Hotel. Largely due to the fact that the western cliff has eroded heavily where (see DR15) there is more vulnerable rock. The hard rock had been less effected by erosion but has still retreated 190 feet aprox. Where riverbed runs has been very little erosion, 100 feet aprox, this could be due to sea walls being in place.
2000 – DR18
When 2000 map covers 1898 map, it clearly shows where most the recession has been. Entrance to the bay has received most of the recession by 400 feet aprox on each side, as the sea hits the body of water in the bay and refracts of the cliffs there is a lot less erosion and the inside of the bay has been eroded by about 100 feet maximum. The eastern cliff face has been hardest hit with very rapid erosion of the beach leaving the cliff face exposed as it is today.
Wind Rose Diagram – DR 19
Wind Rose diagram shows how many days from a 7-year period the wind blew form a certain direction. From my diagram I can see that the wind blew mainly from the South West, evidence of this can be seen in DR16-18 and DR1- 4, whereby the northeastern cliff face is being sub-aerially eroded at a rapid pace.
The Royal Albion Hotel (site 1) appears the receive most of the waves in my investigation and this is a good indication of effective management. The sea wall and riprap in this area are holding back very constant and strong attrition from the sea. The hotel has been in place for over 100 years and has not yet been at risk of erosion from the sea. The defence measures taken in this area are the most extreme of the entire bay and in good reason. Throughout the history of the bay the hotel has been the highest source of income and tourist facility in the area and so needs to be protected. By using my wave count I can get more proof that the defence measures may be the correct way forward.