EQ4- coastal management

Question 1

terminal groyne syndrome

Answer 1

-groynes cause sediment buildup on one side of the groyne(in direction of LSD) but starve the opposing side
-EG south of mappleton: used groynes but to the south materials are transported away from the beach but not replineshsed so at low tide its exposed+little sediment. led to ^ erosion+slumping. localised rate of erosion exceed 10m/year

Question 2

hard

groyne

Answer 2

-stone or timber fences built perpindicular to coast+ spaced along beach
-prevent LSD movement of sediment+encourage deposition to build a higher+wider beach
-cost £150-250 per metre
-EG hornsea, withernsea+ mappleton

Question 3

hard

sea wall

Answer 3

-concrete w steel reinforcement+deep piled foundatiosn. can have a stepped or bullnose profile, to dissipate wave energy
-physical barrier against erosion+flood barrier
-designed to dissipate not reflect wave energy
-destruction of natural cliff face+foreshore enviroment+can reduce beach volume if reflective+look unappealing
-cost £3000-10,000
-EG: porthcawl, holiday resorts: Hornsea+withernsea

Question 4

hard

rip rap
(rock armour)

Answer 4

-large igneous/metamorphic rocks in front of sea walls/cliffs to absorb +dissipate waves
-often at base of sea wall to protect them from undercutting + scour
-no longer cheap+may move in severe weather+vegetate overtime
-£1300-6000
-EG withernsea+easington

Question 5

hard

revetment

Answer 5

-massive stone,timber or interlocking concrete slopping structures which r permable used to reflect rather than resist waves+reduce swash distance by encouraging infiltration
-reduce erosion on dune faces+mud banks, +encourage deposition
-costly+dont cope well w v strong waves, may become vegtated
-EG Easington gas terminal

Question 6

hard

offshore breakwater

Answer 6

-large igenous or metamorphic rock boulders (offshore riprap)
-reduce power of waves offshore+reduce erosive force
-encourages deposition between breakwater+beach can interfere w LSD
-mimic natural bars+reefs. can be built using waste material
-possible ecological impacts+may not work at large scale
-may not work large scale

Question 7

scouring

Answer 7

when water erodes the sediments that surround the base or support structures for bridges, sea walls, roads, and other man-made buildings

Question 8

soft

dune stablizing

Answer 8

-fences used to reduce wind speeds
-dune then replanted w marram +lyme grass to stabilise surface
-reduces erosion by wind+water
-fencing costs £400-2000 per 100m+replanting £1000 per 100m
-replanting can be very cost effective long term

Question 9

soft

cliff regrading+drainage

Answer 9

-cliff lsope angles reduced to ^stability
-revegetated to reduce surface erosion
-incliff drainage reduces porewater(cost effective) pressure+massmovement risk
-drained cliffs can dry out +lead to collapse/rockfalls
-£1million per 100m
-can be disruptive during construction
EG
CD=small scale at easington
CR=mappleton

Question 10

soft

beach nourishment

Answer 10

-artifical replenishment of beach sediment to:
-replace sediment lost by erosion, enlarge beach so it dissipates wave energy+reduces erosion n ^ amenity value of beach
-£20 million per km of beach
-ongoing costs r high
-sediment mustnt be sources from elsewhere in sediment cell

Question 11

soft engineering

Answer 11

-works w natural phsyical systems+processes to reduce coastal erosion+flood threat
-less obvious+intrusive at coast
-may be cheaper in long term
-not suitable for all coasts
-involves accomadation working w natural processes

Question 12

hard engineering

Answer 12

-involves control. used to overcome natural processes-stop or alter them (eg massmovement+erosion)
-reassuring, more resistant, can be used by tourists, a one off solution that could be used for decades
-requires lots of maintance, costs normally v high, even well designed engineering r prone to failure, coastlines r made unattractive+needs of coastal ecosystem r usually overlooked, defences built in 1 place frequently have adverse consequences further along coast

Question 13

sustainable management

Answer 13

-involves adjustment working to secure future of coastline
-can lead to local conflicts in many places
-its managing the wider coastal zone: people + their livelihood, social+cultural well-being, safety from coastal hazards, +minimising environmental impacts.

Question 14

sustainable coastal management

coastal communities r at threat bc

Answer 14

-rising global sea levels, but uncertainity about scale+timing of rise
-^frequency of storms +possibility of ^ erosion+flooding
-eg tuvalu, bangladesh

Question 15

Sustainable coastal management types:

Answer 15

-Managing natural resources=long-term productivity
-Managing flood + erosion risk where possible, or relocating to safe areas
-Creating alternative livelihoods before existing 1s r lost to the sea
-Adapting to SLR by relocating, alternative building methods + water supplies
-Educating communities to understand why change is needed + how to adapt.
-Monitoring coastal change + adapting to unexpected trends

Question 16

Adopting sustainable coastal management may lead to conflict because:

Answer 16

-coastal natural resources may have to be used less in order to protect them -some people lose income
-relocation may be needed where engineering solutions are too costly or not technically feasible
-some erosion and/or flooding will always occur, as engineering schemes cannot protect against all threats.
-future trends, eg SLR, may change, creating uncertainty and the need to change plan.

Question 17

how r coastal management decisions made?

cost benefit analysis

Answer 17

-considers social+economic aspects of a stratergy
-the benefits of a scheem (new businesses/jobs+savings in lives n property) r divided by costs of building+maintaining it

Question 18

cost benefit analysis: North Norfolk

Answer 18

-policy here=no active intervention
-to defend village would have an impact on wider coastal management plan: happisburgh would end up as promontory(high rock), blockin LSD+cause eorison downdrift
-long term plan= managed realingment, this would involve property being lost

Question 19

CBA: north norfolk
COSTS

Answer 19

-£160,000 could be available to Manor Caravan Park to assist in relocating to a new site
-Affected residents could get up to £2000 each (a total costs of £40-70,000) in relocation expenses + cost to council of finding plots of land on which to build new houses.
-Grade 1 listed St Mary’s Church and Grade 2 listed Manor House would be lost.
-Social costs as the village is slowly degraded, including health effects and loss of jobs.

Question 20

CBA: north norfolk
BENEFITS

Answer 20

-By 2105, between 20 and 35 houses would be ‘saved’ from erosion, with a combined value of £4 million - 7 million
-45 hectares of farmland would be saved, with a value of £945,000
-The Manor Caravan Park would be saved, which employs local people.

Question 21

how r coastal management decisions made?

enviromental impact assesment/bipolar

Answer 21

-try to asses effects any stratergy will have upon an area
-especially important along coastlines as attrractive scneary+ecosytsems r valuable tourists assests

Question 22

how r coastal management decisions made?

feasibility studies

Answer 22

-look at technical merits of a particular scheme +site
-considers all aspects n determines liklihood of it succeeding
-it may be denied primarly by return investment=so will project may enough profit to justify investment
-is engineering planned suited to local geology or coastal processes?

Question 23

how r coastal management decisions made?

risk assesment

Answer 23

-involves taking decisions in light of likely recurrence interval+what is at risk
-insurance+legal claims will make this important considerations in future

Question 24

how r coastal management decisions made?

shoreline management plans

Answer 24

-try to decide most appropriate scheme for each part of litoral cell(11 in england +wales), in discussion w parties
-coastal groups have been established based on litoral cell boundaries
-production= appointment of expert firms of consulting engineers to undertake study of all issues eg land use, enviroment protection, economics+action of coastal processes
-final report establishes management policy for coast defences by dividing into seperate management units+making specific recs for each unit

Question 25

SMP time periods

Answer 25

-called ‘epochs’
-Up to 2025
-2025-55
-2055+

Question 26

SLMP= 4 options

Answer 26

-do nothing: carry out no coastal defence activity expect for safety measures
-hold the line: by intervention, hold existing defence where it is
-advance the line: by intervention, to move existing defence seaward
-retreat the line (managed retreat): by intervention, to move the existing defence landward

Question 27

littoral/sediment cells

Answer 27

-linked system of sources, transfers and sinks of sediment along a section of coastline.
-they r isolated from adjecent cells+managed as a holistic unit
-consists of zones of erosion (eg shreline bluffs), transportation (eg beaches)+deposition (eg spit)
-11 in england+wales
-each is managed as whole unit or sub unit- in both a SMP used +further divided into sub cells
-smps extend across council boundaries so many work together on agreed smp to manage an extended stretch of coastline

Question 28

Intergrated coastal zone management
(ICZM)

Answer 28

-its coastal management planning over the long term, involving all stakeholders, working w natural processes + using ‘adaptive management’, i.e. changing plans as threats change.
-holistic approach
-dates from rio earth summit in 1992

Question 29

iczm characteristics

Answer 29

1. entire CZ=managed, not just narrow zone where breaking waves cause erosion + flooding. inclds all ecosystems, resources + human activity in the zone.
2. recognises importance of CZ to people’s livelihoods as, globally, v ^ numbers of ppl live + work at coast - but their activities tend to degrade the coastal environment.
3. recognises that management of the coast must be sustainable, meaning economic development has to take place to improve quality of life of ppl but that this means to be environmentally appropriate at equitable.

Question 30

conflicts

winners vs losers

Answer 30

winners: people who gain from a decision, either economically (their property is safe), environmentally (habitats are conserved) or socially (communities can remain in place)
losers: ppl likely to lose property,business/job, forced to move, or see the coastline be ‘concreted over’ + see this as an environmental negative.=normally poorer ppl like farmers.
-happens as smp areas made but some r protcted n some arent +local govs (DEFRA) have limited resources meaning not all places can be protected
-blackwater estuary all worked together+agreed

Question 31

conflicts

developing world

Answer 31

-eg maldives,vietnam+west africa erosion is rapid bc of:
* upstream dams reducing sediment supply to the coast + disrupting local sediment cells
* rapid unplanned coastal development, urbanisation+development of tourist resorts w piecemeal defences+no overall plan
* widespread destruction of mangrove forests for fuelwood+shrimp-ponds, exposing soft sediment to rapid erosion.
-poorest=losers