The Shared Waters Enhancement & Loughs Legacy (SWELL) is a four-year, €35m project focused on the construction of new wastewater treatment works and upgrades to sewerage networks on both sides of the border to address wastewater pollution in Carlingford Lough and Lough Foyle.
Led by NI Water and working in partnership with Irish Water, the Agri-Food & Biosciences Institute (AFBI), Loughs Agency and East Border Region – SWELL is being funded as part of the EU’s INTERREG VA Programme, managed by the Special EU Programmes Body (SEUPB).
Reaching the halfway stage of the project, Martin Gillen, NI Water Programme Lead for SWELL commented, “We are delighted to successfully commission new wastewater infrastructure at Warrenpoint Wastewater Treatment Works and Newpoint Wastewater Pumping Station (Newry) located in the Carlingford Lough drainage basin and at Strabane Wastewater Treatment Works and Donemana Wastewater Treatment Works located in the Lough Foyle drainage basin.
“The work carried out at these key NI Water sites involved extensive upgrades of the existing wastewater assets to improve the quality of discharge to the respective waterways which impact on the shared waters of Carlingford Lough and Lough Foyle.
“The completion of these four sites marks a major milestone in the overall SWELL project and I would like to thank NI Water’s project management support team from McAdam Design and Construction Consultancy Services and all our local contractors – GEDA, Water Solutions Ireland, GRAHAM, Enisca, BSG Civil Engineering and Deane Public Works – who have worked tirelessly through very challenging times to successfully deliver this new infrastructure.”
Neal Kerr, Director for McAdam Design was proud to have supported the Partners through all the stages of the project from the initial application process to INTERREG, concept design, commercial and project management of construction projects, model management, and project communications.
Commenting on the works, Neal said, “The main challenges included helping prepare and deliver a project approach which involved several different supply chain partners working on four geographically separate construction projects, but all designed to deliver common outcomes.
“Adopting a collaborative approach and ensuring good communication processes helped ensure that we were all pulling in the same direction.”
SWELL partners, Irish Water will deliver a further four projects at Lifford, Killea and Carrigans in County Donegal and in Omeath, County Louth. Due to get underway in spring 2021, the Irish Water works, together with the NI Water upgrades, will deliver cross-border water quality enhancements, which will help contribute towards improving water quality in Carlingford Lough and Lough Foyle.
With match-funding for the SWELL project provided by the Department of Housing, Local Government and Heritage in Ireland and the Department of Agriculture, Environment and Rural Affairs in Northern Ireland, the SWELL project will culminate in the development of an innovative ecosystem legacy model.
Adele Boyd, Senior Scientific Officer with AFBI, explains how this unique model is being developed, “The SWELL ecosystem model will link various aspects of environmental modelling such as urban drainage models, catchment models, coastal models and ecological models, undertaken within the catchments and the respective loughs over the lifecycle of the project.
“When fully developed, the SWELL ecosystem model will be able to track the pathways of nutrients and contaminants of wastewater, industrial or agricultural sources to determine their impact on the receiving waters. Importantly, this legacy model will assist the water utilities and regulatory bodies on both sides of the border by identifying best approaches to achieving further improvement of overall water quality in the future.”
Underlining the importance of the project, Gina McIntyre, Chief Executive of the SEUPB said, “Greater levels of cross border collaboration are essential so that we can improve the water quality of our shared waters and meet the relevant standards under the Water Framework Directive.
She continued, “SWELL is one of the highest value projects to be funded under the EU INTERREG VA Programme and as such represents a significant long-term investment in our natural water resources. Key infrastructure is now in place, and despite current restrictions, the project is delivering upon its objectives. I would also like to commend the SWELL partners, on both sides of the border, for the innovative solutions that they are making, to ensure that this project will be delivered on time.”
Newpoint Wastewater Pumping Station
Upgrade provides protection to the extensive shellfish harvesting in Carlingford Lough…
Newpoint WwPS is the terminal pumping station for the City of Newry, meaning that all flow from Newry and surrounding area arrives at Newpoint WwPS before being passed on to Newry Wastewater Treatment Works (WwTW).
Continued catchment growth and excessive flows arriving at the pumping station presented a significant pollution risk and a potential barrier to achieving EU Water Framework Directive ‘good’ water quality status for the Newry Estuary and Carlingford Lough.
Newpoint WwPS was previously equipped with three wastewater pumps that transfered flow (approximately 500 litres per second) 1km to Newry WwTW, as well as four storm pumps that pump storm water flows to two storage tanks within the WwPS site.
The provision of improved operational control and installation of coarse and fine screening equipment at the Newpoint WwPS site provides protection to the extensive shellfish harvesting areas within Carlingford Lough.
GRAHAM had overall responsibility for the successful delivery of the Newpoint WwPS upgrade under the SWELL project, from Early Contractor Involvement through to project handover. This included the installation of coarse screening equipment to protect the existing pumps on site from blockages and potential loss of wastewater to the adjacent Newry River. Fine screening was also installed on the storm tank overflow to provide further protection to the river during periods of prolonged heavy rainfall. Installation of new waste skips and associated infrastructure safely store the screenings for subsequent disposal off site. Works also included the installation of a new NIE substation within the confines of the existing site, to provide additional resilience against power outages to the plant in future.
Commenting on the project, Mark Little, Contracts Manager for GRAHAM said, “The scheme involved a range of construction techniques and challenges, which had to be fully considered, eliminated, or managed appropriately as design and construction work progressed on site.”
Such challenges included a restricted site area, extremely poor ground conditions and the need to deal with existing high wastewater flows.
“Detailed methodology, programming and BIM modelling completed during the pre-construction phase ensured a thorough review of phasing was completed, so risks identified at the design stage were discussed and eliminated where possible.
“Thorough site investigation was carried out within the footprint of the site, to confirm the underlying conditions, to develop the permanent designs and subsequent temporary works requirements in the form of cofferdams and a well point dewatering system.
“Due to the poor strata encountered during the site investigation, permanent piling was completed on all the permanent structures and interconnecting pipework within the site, to ensure the structures and pipework were suitably supported.”
In conclusion, Mark said, “This project is a great example of positive stakeholder management from Early Contractor Involvement through to project completion. Successful delivery of this challenging scheme reinforces our commitment to NI Water, and we look forward to continuing our long relationship with them on future projects.”
Donemana Wastewater Treatment Works
Upgrade will help achieve EU Water Framework Directive ‘Good’ status at both Lough Foyle and the Burn Dennett River…
In service for nearly 50 years, NI Water has undertaken continued investment in the maintenance of Donemana Wastewater Treatment Works to achieve discharge compliance levels. But due to increasing population demands and greater pressure being exerted on the wastewater treatment works, some of the assets were approaching the end of their design lives.
The replacement works, using modern technology, was constructed as part of the EU-funded SWELL project. This hi-tech wastewater treatment solution will improve the quality of discharge and provide increased environmental protection for the Burn Dennett River and thus the Foyle Estuary for many years to come.
The replacement WwTW has been designed to serve a projected population of 1,217 and was constructed within the confines of the existing NI Water-owned land. The investment entailed a refurbished inlet works, two new primary settlement tanks, three new rotating biological contactors (fully enclosed tanks with built-in treatment capability), two new final settlement tanks, a refurbished storm tank and a new sludge holding tank.
Deane Public Works was appointed by NI Water as the main contractor and provided multi-disciplinary design, project and supply chain management and all civil engineering works for the contract from start to completion.
“The project faced two main problems,” explained Manus O’Kane, from Deane Public Works. “These included the construction of a new treatment works on a very restricted site with difficult terrain, while keeping the existing process operational for the duration of the works.
“To overcome these issues, we purchased two new innovative and energy-efficient zero tail swing Kobelco excavators with roto-tilt hitches grabs to safely deliver the site works in the tight areas between the new items of process equipment.
“A significant innovation to maintain the existing process and ensure it remained operational, was the deployment of a temporary treatment plant, which met all discharge consent standards for the duration of the works.
Water Solutions Ireland (WSI) was responsible for the full design and build solution for Donemana WwTW. “We developed and delivered a full turnkey MEICA and process solution for the replacement WwTW,” said Patrick Cunningham, Contracts Director for WSI.
To overcome the challenge of the restrictive site, WSI identified redundant assets under the client’s portfolio that could be refurbished to form part of a final temporary treatment solution. WSI engaged the supply chain to fully develop a compact, low maintenance temporary treatment solution that would provide full treatment during construction.
Patrick commented, “The installation of a temporary plant solution was effective in reducing overall project costs due to a reduced construction programme, reduced Health and Safety risks and easier maintenance of treatment performance levels during the construction period”.
By employing best practice methods, the project achieved Performance Beyond Compliance Certification under the Considerate Constructors Scheme.
Strabane Wastewater Treatment Works
Strabane WwTW is located to the north-western edge of the town and has been in operation since 1974…
The existing Strabane WwTW was upgraded in 2004 to serve a design population equivalent of 38,000, with treated effluent being discharged to the River Foyle.
Northern Ireland Water has undertaken continued investment in maintaining the site to achieve discharge compliance levels. However, with assets approaching the end of their design lives, and more recently, increased flows arriving at Strabane WwTW causing regular flooding of the inlet screen chamber, the plant required an upgrade.
During significant storm events, flooding at the inlet screens can result in overtopping/bypassing of the fine screens and inlet pumping station and ultimately can lead to the discharge of wastewater via the storm tanks to the adjacent River Foyle.
A detailed analysis of the catchment conducted for the SWELL project estimated that the existing works received load from a population equivalent of 24,806, reflecting a downturn in trade within the town in recent years.
This means that, in comparison to its original design capacity, Strabane WwTW was biologically underloaded. The plant remained in satisfactory condition and generally capable of achieving its current consent requirements for the quality of treated effluent discharged to the River Foyle. However, the inlet chamber fine screens had reached the end of their useful life and no longer met current Water Industry specifications and standards.
The upgrade at Strabane included the construction of a new inlet reception chamber with new screw pumps to lift storm flows to the existing preliminary treatment works. This solution provides Strabane WwTW with the ability to better deal with storm events, making it more resilient to climate change impacts and providing additional protection to the surrounding environment.
BSG Civil Engineering was responsible for the design, construction (civil and MEICA), commissioning and operation of the upgrade.
This complex project came with some major challenges such as keeping the existing works operating and compliant while building the new inlet works. “This was achieved by the installation of 900mm DI diversion pipework and manholes,” explained Aidan Diamond, Project Manager for BSG Engineering, “that allowed for isolation of the existing reinforced concrete structure so that a new structure for the screw pumps could be installed offline while all flows were diverted away.”
Due to their length, the 18m screw pumps were classed as abnormal loads and needed to be delivered to the site from Dublin Port before 6am in the morning. Likewise, due to logistics issues and Strabane being a busy sludge import facility, careful planning had to take place to allow for full installation by 12 noon on the same day as delivery.
Commenting on the completed project, Aidan said, “BSG was delighted to have the opportunity to share our wealth of knowledge and expertise at an early stage through the Early Contractor Involvement (ECI) process. This forward-thinking approach allowed BSG to feed into the design development phase, creating innovative 3D models that gave the client confidence to know that they were getting a robust, maintainable solution.”
Warrenpoint Wastewater Treatment Works
Constructed in 1976, Warrenpoint WwTW serves the town and the neighbouring villages of Rostrevor and Burren…
The previous Warrenpoint WwTW was designed for a population equivalent of 16,195, with treated effluent being discharged via a 300m long, 450mm diameter outfall pipe directly into Carlingford Lough.
Over 40 years on, investigations found that the plant was receiving a load from a population equivalent of 16,259, meaning that it was operating beyond its intended design capacity.
The previous operational problems were due to excessive flows being pumped to the inlet works. This problem was exacerbated by network infiltration tidal ingress and inadequate flow balancing at the WwTW. This resulted in un-attenuated flows and premature use of storm tanks in dry weather conditions. This factor was considered to be a significant potential source of wastewater pollution to Carlingford Lough, contributing towards the failure to meet ‘Good’ Water Framework Directive Status status.
The improvements delivered under the SWELL project concentrated on addressing overloading at Warrenpoint WwTW and the potential loss of wastewater in order to improve water quality within Carlingford Lough.
As main contractor, Geda Construction had overall responsibility to deliver the project on time and within budget, which they succeeded in doing by working in collaboration with key suppliers and sub-contractors to identify and prepare for key milestones for the project.
One of the key challenges involved the pouring of 700m3 of concrete for the aeration tank base. “This involved liaison with DFI Roads to close the hard shoulder of the A2 carriageway,” explained Paul McElroy, Contracts Manager for GEDA Construction. “The pour commenced at 6pm and was completed at 6am to avoid traffic congestion around the major link city, Newry.”
Atkins provided civil, structural and geotechnical design services. “We were involved from the initial enabling and investigatory works through to optioneering/outline design and detailed design for construction,” said Robin Andrews, Project Manager for Atkins.
“Warrenpoint had a complex arrangement of interconnecting pipes and services, and managing the interfaces between existing and new infrastructure was a key element of the design. Atkins adopted BIM Level 2 protocols from the outset and developed integrated 3D models for existing and proposed works that allowed designers, contractor and client team to collaborate from the optioneering phase through to construction and commissioning.”
Water Solutions Ireland (WSI) carried out a full turnkey MEICA and process design and build solution for the SWELL upgrade.
Commenting on the completed project, Patrick Cunningham, Contracts Director for WIS said, “To deliver the benefits of improved flow management and remove the potential for loss of biological loading during dry weather conditions, Water Solutions was tasked to review the existing works and develop a full replacement treatment works capable of treating a design of 21,000PE.
“The opportunity to put in practice the company motto of “Working to protect the Environment” through a collaborative working relationship with the SWELL team was fantastic.”