The River Erne Ireland typifies everything of the beautiful Irish countryside.
The 120km river splits lush green fields as it winds its way through several interconnect loughs nestling among the Drumlin hills of Co Cavan and south Fermanagh.
The river is also a world famous salmon and general fishing area for the local population.
Therefore it was key for Ferrovial Agroman UK and Ireland, contracted to upgrade his crucial part of the N3 Belturbet Bypass, to implement a sustainability and environment plan to preserve this natural wonder when completing the River Erne Bridge.
The 142m cable stayed extradosed bridge is the first of its type installed in the country and the second major structure on the project.
Ferrovial Agroman HSQE Director Robert Hackett said:
“Given the environmental sensitivity of the area, the works were under constant intermittent supervision of the Inland Fisheries Ireland and the Irish National Parks and Wildlife service. So building a bridge with piers partly inside the river required extensive planning and preparation as to have minimal impact on the river itself. In addition to this, a potable water source is drawn from the river just 500M downstream of the bridge site.”
"To overcome these challenges, the Ferrovial Agroman Environmental team undertook an extensive water preservation plan which included the constant monitoring of the pH and suspended solids levels created by the works.”
The 4 main bridge bases were below the water level, therefore water entering the excavations and cofferdams was pumped to multiple settlement ponds located around the site (up to 8 No. 6“pumps at one time during the height of the works).
These settlement ponds slowed the velocity of the water allowing the suspended solids to be removed prior to the water re-entering the river. As well as water directly created by the project through pumping, many streams in surrounding fields, which had historically drained the land and was naturally filtered by the grass before entering into the river, were cut off by the works.
To preserve this natural filtration system, the streams were channelled into the settlement pond system. This ensured that any water which had gathering solids in areas where the grass was removed, would still be filtered before discharging into the river.
Project Manager Alfredo Sobrino said:
“Given the proximity of the bridge to Belturbet town the project team also needed to be aware of the local residents, a church just 350m away and fishermen who still had a right of way along the river banks, and a local Primary school, Deliveries and construction operations had to be sequences and routed to avoid traffic congestion, noise pollution, with Ferrovial Agroman supervisors in constant communication with the locals to plan operations so as to minimise impact on the community.”
Oil booms were also placed around and downstream of the works to prevent any spills making their way into the river proper.
These were cleaned and replaced regularly. Performing and delivering responsible solutions is integral to the Ferrovial Agroman UK and Ireland team.
Through their successful environmental and sustainability plan, the Erne River bridge was delivered without impacting on the eco system