Hard Engineering

• Hard engineering involves building artificial structures which try to control natural processes
• Seawalls are often recurved which means waves are reflected back on themselves
• Sea walls often have a promenade on top of them which are popular with tourists
• Sea walls cost £5000/m
• Rock armour cost £1000 to £3000/m
• Rock armour is a barrier of large boulders placed in front of a cliff or sea wall to absorb wave energy and reduce backwash
• Rock armour is versatile because it can be placed in front of a sea wall, extending its life span
• Gabions are wire-mesh cages filled with pebbles or rocks and as water enters the cages, wave energy is absorbed and dissipated
• Gabions are £110/m
• Groynes are wooden barriers constructed at right angles to the beach to retain the material
• Groynes cost £5000 each
• Groynes are relatively cheap and if well maintained they can last 40 years