COASTS: Hard & Soft Engineering Flashcards
What do groynes do? Hard/soft?
Break waves and slow down LSD. Built perpendicular to coastline. HARD
What do rock bunds/rip rap do? Hard/soft?
Row of rocks along beach to absorb wave energy. Allows build up of a beach. HARD
What do gabions do? Hard/soft?
Steel mesh cages filled with small rocks. Absorb wave energy. HARD
What do revetments do? Hard/soft?
Wooden/concrete, absorb wave energy, still allow flow of sediment. Built at base of cliffs. HARD
What do offshore bars do? Hard/soft?
Rows of boulders built to break waves before they reach the beach, to reduce wave energy significantly. HARD
What does beach replenishment do? Hard/soft?
Pumping sand/shingle back onto beach to replace eroded material. SOFT
What does beach reprofiling do? Hard/soft?
Changing shape of beach so that it absorbs more energy and reduces erosion. SOFT
What does replanting vegetation do?
Planting resistant plants e.g. grasses to help stabilise low lying areas. SOFT
What does beach recycling do? Hard/soft?
Moving material from one end of beach to other end to counteract LSD. SOFT
Advantages of HARD engineering? (5)
- Reduces wave energy.
- Don’t have to control them.
- Rock armour looks natural.
- Groynes are usually cheap.
- Sea walls protect land and buildings behind.
Advantages of SOFT engineering? (4)
- Work with natural processes.
- Based on protecting/preserving beach and environment.
- Less expensive.
- More natural looking.
Disadvantages of HARD engineering? (6)
- Eye sores, unattractive.
- Expensive, usually between £3-8 million per km.
- Not always environmentally friendly.
- Wooden structures rot.
- Cost of maintenance is high.
- Groynes prevent sand from moving along coastline, causing build up.
Disadvantages of SOFT engineering? (3)
- Requires on going maintenance.
- Maintenance can become expensive.
- Not sustainable where areas are very developed (would need hard engineering instead/also).
What are the 4 Shoreline Management Plans? (SMPs)
- Hold the line
- No active intervention
- Managed retreat
- Advance the line
What does a sea wall do? Is it hard or soft eng?
Protects cliff from erosion, as it reflects wave energy. HARD