Greystones Harbour and North Beach Plan is a Public Private Partnership (PPP) between Wicklow County Council and SISPAR to regenerate the Old Victorian harbour area and extend Greystones town to include a new 16 acre public park.
The development comprises a new harbour, the creation of a new 230-berth marina, 5,500m2 of commercial units and 341 residential units. Public facilities valued in excess of €50m are also included in the plans.
Arup carried out the design of permeable breakwater roundheads that reduce wave heights at the harbour mouth and the sustainable approach to dealing with rapidly eroding cliffs. These new coastal protection measures retain and protect the existing cliff walk in an area that has suffered the effects of coastal erosion.
Arup adopted the most sensible and cost effective approach of managing the natural retreat of the cliff, rather than trying to stop it. Beach nourishment was adopted in areas where the erosion would have been unsustainable.
Breakwaters and marina
The main structural elements of this complex maritime project are two breakwaters with a total length of 530m. The contractor wanted a design that would minimise the amount of floating plants and would that way minimise the effect the weather had on the construction programme.
Arup therefore designed the breakwaters to be built using pre-cast concrete blocks. The seaside face of the breakwater is protected by a revetment made up of 3-6tn rock armour and 14tn antifer blocks.
As part of the specialist transportation planning and traffic engineering input, Arup undertook the traffic assessment and developed the construction traffic management plan and programme.