Hard And Soft Engineering Flashcards
Why does the coast need protection?
Half of the world’s population live within 60km of a coast and three-quarters of all large cities are at the coast.
What is hard engineering?
Man-made structures using resistant materials such as concrete, wood and metal to control natural processes.
What is soft engineering?
Natural materials and systems which work in conjunction with natural processes.
What is a shoreline management plan?
- formal document for each sediment cell outlining long term management decisions
What is the integrated coastal zone management (ICZM)?
A dynamic, multidisciplinary process to promote sustainable management of coastal zones.
What are Sea Walls?
- curved walls often made of concrete
- aim to dissipate wave energy - recurved structure to deflect the energy of one wave back into the next approaching wave
Cost and lifespan of sea walls?
Cost: £200,000-£500,000 per 100m
Lifespan: 30-50 years +
What are Groynes?
- cross-shore structures designed to reduce longshore drift on open beaches. Rock is often favoured to construct, but timber can also be used.
- make the beach larger - more protection to the coastline and there is increased opportunity for recreation
Cost and lifespan of groynes?
Cost: £10,000 - £100,000 per groyne
Lifespan: 25 years (Timber)
What is Rock Armour (Rip-rap)?
- consists of large boulders places in front of a cliff or sea wall. The large surface area and gaps helps to dissipate wave energy.
- often used in areas with important back shore assets where sea walls are not cost effective or environmentally acceptable
Cost and lifespan of rock armour?
Cost: £100,000 - £300,000 per 100m
Lifespan: Can be unlimited
What are gabions?
- wire cages filled with smaller stones that can be found locally
Cost and lifespan of gabions?
Cost: £100,000 - £300,000 per 100m
Lifespan: Can be unlimited but gabion baskets can rust within 10 years
