NEWRY FLOOD ALLEVIATION SCHEME

The purpose of this Infrastructure scheme is to protect properties located at Armagh Road, Downshire Road, Belfast Road, Craigmore Road, Chancellor’s Road and Greenbank Industrial Estate, Newry, from flooding. The works were undertaken by AG Wilson as Principal Contractor on behalf of DFI Rivers and carried out on 4. sites within Newry. Works commenced Aug 2021 along the Armagh Road Drain and involved the upgrade of the existing culvert the entire line of the watercourse; construction of a section of flood defence wall, construction of a flood defence on both sides of the Derrybeg River and installation of a new culvert at Newry Leisure Centre. Upgrading the existing Downshire stream culvert required the construction of a U-channel within the existing watercourse. Construction of a new inlet grille involved extending the existing twin 900mm Ø culverts to meet the grille area. Two U-Channel sections included floodgates. Construction of two flood defence walls at Greenbank Industrial Estate consisted of sheet piling and flood bunds along the 1km stretch of the Knox-Pebbles Drain. Works at Craigmore Road required the construction of a new grille and dredging of the existing watercourse to remove any overgrown vegetation within the channel.

Complexity

The delivery of this flood alleviation scheme posed several challenges and engineering solutions were required along a 40m section where it was impossible to install 1350mm pipes due to a lack of cover from the top of the pipe to ground level. To overcome this constraint, a dual-pipe system was installed. Service crossings also presented challenges, especially during the installation of sheet piling where seven services were found to cross the river at varying points along the route. To overcome this the ground was reduced to expose all services and 7m H beams were driven down each side of the service with concrete panels placed between the beams. This meant that services were not affected, and the panels were below water level to maintain flood defences. Due to the proximity of the electric cable feeding the local PSNI station a new design was required utilising the rock at the face of each bank to form a channel and minimise the requirement for excavation in the stream bed.

Build Quality

To achieve a high standard finish, U channels along the Downshire road section were precast. This ensured no waste and a fullstrength product from point of installation. This method of buildability also eliminated the risk of pollution to the watercourse. Channels were procured from our supply chain member, approved and evaluated to ensure the quality of their product and ability to offer capital efficiencies and whole-life value for money. As the product was already cast it was easier to stay on programme with planned deliveries and within budget due to agreed costs.

HEALTH & SAFETY

AG Wilson managed on-site Health and Safety under ISO 45001:2018 Management System with safe systems of work in

PROJECT FOCUS

Newry Flood Alleviation Scheme

Client: DFI Rivers / AMEY

Value Range: <5M place. Site-specific control measures included trench box systems utilised in excavations and recovery fall arrest davit winch working in manholes. Where existing paths or areas required temporary closure, all access points were robustly secured, with adequate signage erected.

Social Value

The site was registered to the Considerate Constructors Scheme and achieved an excellent performance level and ranked in the top 70% of miscellaneous sites nationwide. We adopted best-practice sustainable initiatives. These included but were not limited to, opportunities for local unemployed, apprenticeships, support for a local charity and school, promoting careers in construction and proactive environmental enhancements. The site supported a positive impact on the local community. Works were programmed to minimise inconvenience to the public along with the implementation of a community engagement plan. Covid compliant notice boards were erected keeping the public informed on progress to date & upcoming works.