Defending a coast without passing the problem on

Geography · Physical Geography · ages 14-16

Name ______________________ Date ____________

What does managed retreat mean?
- Repairing defences along the present shoreline
- Adding sand to maintain the existing beach
- Planning an inland move and allowing coastal change
Which pair names a hard defence followed by a soft method?
- Seawall and beach nourishment
- Dune restoration and sand top-ups
- Seawall construction and groynes
A groyne can trap sediment on one beach and reduce supply to beaches further along the drift direction.
Circle one: True False
Which situation gives the strongest reason to investigate managed retreat?
- A repairable wall protects homes at low lifetime cost
- A nourished beach meets needs with affordable top-ups
- Holding the shore is costly and growing less safe for people
Fictional bay: both plans meet the same 15-year target. Costs cover all work over 15 years.
Plan Cost (million pounds) Life or renewal Sand supply beyond
Groynes 7 Last 30 years Reduced
Nourishment 5 Top-up every 5 years Unchanged
Which comparison fits?
- Groynes last 30 years, cost less and cut supply; nourishment needs 5-year top-ups.
- Groynes last 30 years, cost more and reduce supply; nourishment needs 5-year top-ups.
- Groynes last 30 years, cost more and keep supply unchanged; nourishment needs 5-year top-ups.
Choosing a coastal defence only involves engineering; effects on people and public spending do not matter.
Circle one: True False
A plan protects seafront homes, may affect a neighbouring beach and uses public money. Which consultation best matches those stated impacts?
- Seafront residents, engineers and suppliers
- Residents, beach users and the funding authority
- Tourism operators, seafront landlords and the building contractor
Monitoring shows a groyne traps sand and reduces supply to the next beach. Which action directly addresses that sediment shortage?
- Move some trapped sand past the groyne
- Raise a seawall behind the sediment-starved beach
- Build a longer groyne to trap more sand before it passes

Plan	Cost (million pounds)	Life or renewal	Sand supply beyond
Groynes	7	Last 30 years	Reduced
Nourishment	5	Top-up every 5 years	Unchanged

Answer key

For grown-ups. Fold this page away before handing over the rest.

Defending a coast without passing the problem on W1-mt_3Px4N4va3o-s1

Planning an inland move and allowing coastal change · Managed retreat plans a landward change in protection or vulnerable uses while allowing some land to erode or flood.
Seawall and beach nourishment · A seawall is a built structure. Beach nourishment adds sediment to maintain a beach buffer.
True · Trapping sediment can interrupt its movement alongshore.
Holding the shore is costly and growing less safe for people · High costs and increasing safety concerns support investigating retreat. Relocation impacts still need assessment.
Groynes last 30 years, cost more and reduce supply; nourishment needs 5-year top-ups. · Nourishment costs 5 million pounds versus 7 million for groynes over 15 years. It needs five-year top-ups. Groynes last 30 years but reduce sand supply beyond.
False · Protection, possible harms and public costs affect different groups and must be considered.
Residents, beach users and the funding authority · The stated impacts concern protected residents, neighbouring beach users and the authority funding the scheme.
Move some trapped sand past the groyne · Passing some trapped sand onward can help replace the supply interrupted by the groyne.