Client:
Galway Co. Co.
Consultants:
Atkins
Location:
Ballinasloe, Co. Galway
The works consisted of a flood defence barrier approx 1.2km in length which included a 600m section of impermeable clay bund and a 600m section sheet piles flood defence barrier with a RC wall and capping.
15,000 tons of impermeable clay which was sourced locally and tested. The clay was placed in 300mm layers to create a bund which was topsoiled and seeded.
The piled wall, consisting of 400t of MX7 & MX8 sheet piles, were treated with Biguma joint sealant prior to installation with our MOVAX piling equipment and capped off with a RC wall, comprising of 2,000m3 of reinforced concrete.
Extensive storm and foul sewer systems that were serving the 3 housing estates contained within the perimeter of the flood defence barrier, were installed. To accommodate sewers flowing from the protected side to the flood side we had to install various non-return valves on the existing and diverted pipework that would come into operation during flood periods.
These included chamber mounted penstocks and sluice gates to headwalls. Pumping chambers were provided to pump surplus water out from the protected side when sewers were shut off during flood periods. New drainage networks and culverts were constructed with 300mm ø to 900mm ø concrete pipes with Head walls to NRA RCD/500. Temporary works designs and shoring were also required for sections of deep drainage and manhole chambers. Extensive cleaning of open drains in surrounding agricultural land was also carried out.
All works were carried out in an SPA (Area of Special Conservation) and strict pollution control measures were adhered to at all times during construction.