holderness case study Flashcards
holderness key facts
60km flambourough head to spurn head
1m recede a yr (highest europe)
3 miles land lost and 20 villages since roman time
where is holderness
NE england
yorkshire
geology holderness
chalk flamborough head to north bridlington
- cave arch stack stump, wave cut platform
- horizontal bedding planes
boulder clay bridlington to spurn head
-slumping
-sandy beach from cliff erosion
- 1.7m lost per year
- 7m tidle range
spurn point
- 5k long sand spit
-salt marsh and mud flats behind
- hooked
why so much erosion here
500-800Km NE fetch from Norway
warm atlantic ocean current circs N sea adding energy and inc freq destructive waves
depressions and winter storms cause big storm surges and higher sea levels.
more rain aswell so slumping occurs
sea floor very deep
little fricton
little wave energy absorbed
LSD and beaches at holderness
N to S
narrow beaches due to small size of clay so easily removed
destructive waves so little deposition
ocean current meets outflow river humber, flow turbulent, sediment deposited, spurn head formed
sub aerial processes at holderness
mechanical - wet and dry clay
rainwater saturated boulder clay
rotation slump
material removed in suspension
man made processes
groynes
- caused terminal groyne syndrome
£1.9 mill on 2 rock groynes and granite barrier to protect mappleton
- erosion to S (great cowden) has trebled as beach starved and unprotected
impact sea level holderness
slow eustatic rise
inc erosion and flooding
spurn head shrinking
describe flambourough head
chalk resistant and horizontal bedding planes
- wave cut platform
vertical joints lead to cave and geo
wave refraction on headland leads to arch and stack
describe holderness cliffs
boulder clay
rainwater enters and causes slump seawards
- inc by removing vegetation and urbansiation
waves remove slumped material and lsd transports it south (1/2 mill tonnes/yr)
cliffs unprotected
more erosion
describe spurn head
sediment deposited
recurved
salt marsh and sand dune ecosystem behind
what happened at barmston
storm drainage pipe trapped sediment
acted like groyne
led to term groyn syndrome
had to install rock armour
formed bay due to erosion
what happened at ulrome
collapsed roads
forced caravan rollback
no defences
site abandoned
what happened at skipsea
road collapsed into sea
no management
what happened at bewholme atwick
roads into sea
pipes and cables visible
abandoned caravan park
land low economic val
what happened at mappleton
substantial village so defences
lots slumping
boulder groynes
rip rap rock armour (from norway 2mill)
- large beach produced
term groyn synd
- huge crenulated bay
low value land lost
what happened at hornsea
lots coastal management
concrete sea wall which got upgraded to recurved
wooden groynes
riprap to protect sea wall
what happened at aldborough
roads and coastguard station into sea
nothing done
what happened at tunstall
road into sea
nothing done as buildings far back
what happened at withurnsea
well protected
large concrete recurved seawall
extensive riprap
wooden groynes
term groyne syndrome impact holiday park
what happened at spurn
lsd deposited sediment form 3 mile long spit into river humber estuary
used to have groynes as there was road and settlement for pilot boat driver fams but no longer exist
- groynes stopped being maintained
not econ viable to continue
stakeholders in holderness management
national government - have cut budget
local gov and environ agency - east riding council follow gov guidlines
stakeholders eg residents farmers - have no say
environmental stakeholders eg rspb - want cont breeding at spurn head so against groynes
insurance companies - wont insure people if no coastal protection
how much holderness not protected
around 90%
low value farmland
not worth protecting
public defences
paid by gov
bridlington/hornsea/mappleton/ withernsea
-key settlements and gas terminal at easington
private defences
paid by land owners
skipsea/ulrome temp planning permission from council to protect caravan parks
why protect bridlington + what done
25,000 pop + tourists
4.7 of concrete sea walls
timber groynes
why protect skipsea + what done
780 pop
by local land owner
protect caravan site
why protect hornsea + what done
pop 8800 + tourists
1.8km conc sea wall
rip rap
groynes
beach nourishment
steel doors guard beach entrance
sand dunes planted
why protect withernsea + what done
6,500 pop + tourist
2.2km recurved conc sea wall
wood groynes
riprap
beach nourisment
offshore rock armour reef
why protect easington + what done
5000 pop + gas terminal
1km long revetments at terminal site
- 133,000 tonnes rock
cliff drainage
cliffs erode either side
reviewed in 25yrs to see if gas terminal still needed
why protect spurn head + what done
no longer protected as not econ viable
where is hold the line
bridlington
withernsea
hornsea
mappleton
easington
where is do nothing
low populated areas
where is managed retreat
roll back caravan parks
how many SMP section
10
what at section A
no intervention
flambourough will erode
what at section B
HTL - high econ land val from harbour and bridlington town
marina developed retreat may need to occur
what at section C
no intervention
may need to maintain barmston drain
- priv defences ulrome protecting caravan parks removed
what at section D
HTL - protect hornsea as touism
caravan park will erode
more defences may needed
what at section E
HTL only at mappleton
conservation areas may be eroded
assement for N-S transport links
what at section F
HTL to protect withernsea
more defenses may be needed
what at section G
no intervention
assesment N-S transport may be needed
what at section H
HTL only at easington to protect gas terminal
review if terminal still of econ interest in future
term groyn syndrome
what at section I
HTL at lagroon and kilnsea
erosion of conservation area may occur
what at section J
managed realignment to maintain integrity barrier
if unsustainable limited management will be stopped
