West Cavan DBO & Pipeline Works Projects
The project consisted of nine Group Water Supply Schemes and one Public Water Supply Scheme in West County Cavan, coming together as a ‘bundle’ and acting as partners to procure Water Treatment Facilities to satisfy the Drinking Water Regulations and to carry out water conservation works and critical mains replacement to reduce UFW in advance of the Water Treatment Plants coming on line. The project involved a DBO Contract (8 WTPs) and five advance Civil Works Contracts with a combined pipeline length of 61km.
West Cavan Water Treatment DBO Project – the nine Group Water Supply Schemes and one Public Water Supply Scheme in West County Cavan collectively serve approximately 1,400 households in the area and have capacity to provide a total of 3,258m³/day. Works included 8 new Water Treatment Plants, 7 new Precast Reservoirs, 13km of new Pipelines and associated Borehole and Lake intakes. Following completion of the DB elements, the project is currently operating under the 20 year O&M phase.
West Cavan Individual Metering Project – this project consisted of the installation of 1,629 domestic and non-domestic meters, including the replacement of 181 valves and the provision of bulk meters and pressure reducing valves at strategic locations on all 9 schemes.
Doobally GWS Network Improvement Contract – this contract involved the replacement of approximately 8.25km of critical mains, including installation of bulk meters and pressure reducing valves at strategic locations.
Glangevlin GWS Network Improvement Contract No’s. 1 and 2 – These contracts consisted of 5.5km and 7km respectively of critical mains replacement and the installation of bulk meters and pressure reducing valves at strategic locations.
Glangevlin GWS Network Improvement Contract No. 2 – this contract consists of 7km of critical mains replacement and the installation of bulk meters and pressure reducing valves at strategic locations.
Corlough GWS Network Improvement Contracts – this project consisted of 2 No. Contracts involving the construction of 27km of new pipelines varying in diameter from 63mm to 180mm and included critical mains replacement, 2 new Precast Reservoirs, and the installation of various bulk meters and pressure reducing valves at strategic locations within the scheme network.
Services provided by Jennings O’Donovan
The principal services provided by Jennings O’Donovan included Preliminary Reports, Detailed Design with EPANet modelling to individual schemes, Source Development Works, Ecological Studies, Hydrological Analyses, Liaising with NPWS regarding mitigation measures within NHA / SACs, Liaising with stakeholders and GWSs, Part 8 Planning Documentation, Contract Documentation (5Nr Conventional Contracts and 1 DBO), Tender Process (2 Stage including Pre-Qualification for DBO), Construction Supervision and Administration and Handover for all Contracts, including the role of PSDP.
The project which was completed in 2012 proved particularly successful in terms of Water Conservation. UFW prior to the advance and metering Contracts ranged from 40 to 90%, which would have resulted in many of the new water treatment plants unable to meet the scheme demands. Following the advance water conservation works, consumption dropped considerably across the schemes (by 10-50%) and all scheme demands are operating within their respective plant capacities.