Capital Works
Sample Capital Project
Lough Mask Regional Water Supply Scheme
Stage 1, Contract 6, Extension from Ballyheane to Balla
This project involves the construction of a new 400mm Ductile Iron water main between Ballyheane and Balla, which will deliver a quality water supply to Balla and a number of group water schemes, which lie within the area of supply. A total of 22kms of trunk and distribution mains are being constructed by the Councils Water Services direct labour workforce. In addition, 6 no. valve-houses are being constructed along the pipeline route by Pierse Construction Ltd., all at an estimated cost of 6.12m.
Key Project 2003 Background Preliminary Report Water Quality Estimated Water Demand Design of Trunk Pipeline and Storage Phasing of Scheme Land Acquisition and Wayleaves Public Consultation Site Investigation Scope of the Scheme Procurement of Materials Construction of the Scheme Progress meetings and reports Belcarra Group Water Scheme Valve Houses Archaeology BackgroundIn March 1990, P.J. Tobin & Co., Consulting Engineers, submitted a Preliminary Report to Mayo County Council, which put forward a blueprint for the delivery of Lough Mask Water to Balla. The trunk main proposed was designed to cater for a future extension of the Lough Mask Scheme to Kiltimagh as well as providing a reliable supply of potable water for Belcarra and Manulla and all of the group water schemes serviced by the two public water supplies.
Design of Trunk Pipeline and Storage
Land Acquisition and Wayleaves
Preliminary Report
The Preliminary Report established the need for the proposed Stage 1, Contract No. 6 Extension, defining the supply area in the process. It examined the operating experience with the existing schemes, their water quality related to the Drinking Water Regulations 1988 and their existing storage facilities. The Report examined current and projected water demand for the Manulla/Balla area and the likely additional projected demand for the Kiltimagh area as well as the implications of including Kiltimagh and its hinterland as a bulk flow provision at the extremity of the proposed trunk main to Balla. A pipeline route was selected as well as potential sites for storage reservoirs where required, and an estimate of cost was provided.
Water Quality
The Public and group water supply schemes in the proposed supply region are characterised by poor source water quality, inadequate treatment facilities other than chlorination, and little or no contingency storage. The difficulty of protecting these sources from surface organic contamination, and the presence of Iron and Manganese in the larger supplies, led to a recommendation that all of these schemes be integrated into the Lough Mask Regional Scheme as the best practical option for Mayo County Council in meeting its obligations as a Sanitary Authority.
Estimated Water Demand
The Preliminary Report examined population trends within the Balla/Kiltimagh Region of supply and projected a future population of 6900 persons for the region up to the year 2015.
Domestic, Agricultural and Industrial demand was estimated as follows. Domestic Demand 1980m3/day Agricultural Demand 1760m3/day Industrial Demand 700m3/day Total Demand 4440m3/day
Design of Trunk Pipeline and Storage
The design philosophy of the Lough Mask Scheme is based on the provision of adequately sized storage reservoirs throughout the supply area, as this will determine the ultimate capability of the system and its reliability on a local scale. This is because the hydraulic analysis clearly indicates that the carrying of average rather than peak flows in the main trunk lines would greatly increase the residual pressures available at the extremities of the system and particularly the elevation to which storage can be filled by gravity in the eastern areas of the County.
Based on the above the Preliminary Report recommended the construction of a new 400mm diameter trunk main from the existing valve house No. 14 at Ballyheane to a new elevated storage Reservoir (capacity 4,500m3) at Craggagh and a 400mm trunk main from Craggagh to Kiltimagh. Balla and its associated group schemes would be supplied via a new 250mm diameter distribution main between the new Craggagh Reservoir and Balla.
Phasing of Scheme
The Preliminary Report was approved by the Department of Environment, Heritage & Local Government on the basis that the scheme would be phased. Balla, Belcarra and Manulla would be served under Phase 1 while Phase 2 would provide for the construction of the pipeline extension to Kiltimagh and the new 4,500m3 Reservoir at Craggagh.
P.J. Tobin & Co., were appointed to prepare Contract Documents for the Scheme and these were approved by the Department of Environment, Heritage & Local Government in May 2002.
Land Acquisition and Wayleaves
The Land Acquisitions and negotiations on Wayleaves commenced in Spring 2001. Sites for the valve houses were purchased and 80 Wayleave Agreements were negotiated from local landowners. The width of the wayleaves was 23m and they ranged in length from 30m to 580m. Full co-operation was forthcoming from all landowners and no Compulsory Purchase Orders or Compulsory Wayleaves were required.
Public Consultation
Mayo County Council approved planning under Part 10 of the Local Government (Planning and Development ) Regulations, 1994.
Site Investigation
Subsoil Investigations were carried out by Irish Geotechnical Services Ltd. (IGSL) during the second half of 1999 and their report was submitted in August 2000. This stated that rock was a prominent feature over the route of the pipeline between Ballyheane and Manulla with various pockets of poor ground conditions over the remaining portion of the Scheme.
A structural Survey was carried out on all buildings along the route of the pipeline where rock breaking was necessary. This involved a visual inspection of the property with video evidence of any existing faults prior to construction of pipelines.
Scope of the Scheme
This Scheme extends the Lough Mask Regional Water Supply Scheme to Balla including the Belcarra GWS and Manulla GWS and provides for a future extension to Kiltimagh. The pipelines are presently under construction by Mayo County Council Water Services Direct Labour and the Valve Houses were constructed by Pierse Construction Ltd. in 2003. This Scheme involves the construction of:
14,460m of 400mm Ductile Iron trunk water main. 1140m of 250mm Ductile Iron trunk water main. 2240m of 150mm uPVC trunk water main. 4600m of 100mm, 150mm and 200mm distribution water mains for the Belcarra GWS. 6 No. Valve houses.The total length of pipeline to be constructed is over 22km with the total estimated cost of the contract at 6.12 million.
Procurement of Materials
The contracts for the supply of pipes and fittings for this Scheme was advertised in National papers and in the Official Journal of the EU in July 2002 and after recommendations on tenders were approved by the Department of the Environment, Heritage and Local Government, the contracts were awarded in June 2003, as follows:-
Section 1- Saint-Gobain Pipelines Plc., for the supply of Ductile Iron Watermain pipes and bends. Section 2 Radius Plastics Ltd., for the supply of uPVC pipes and bends. Section 3 M&G Ltd., for the supply of Fittings, Valves and ancillary equipment.The total value of these contracts is 1.4 million.
Construction of the Scheme
The Scheme is being constructed by Mayo County Councils Water Services Section Direct Labour Team. To date this is the largest contract undertaken by Direct Labour. There are currently 5 direct Labour crews working in the Water Services Section of Mayo County Council with three crews dedicated to this project. Construction of the pipelines commenced in September 2003.
Initially three compounds were prepared for the delivery of all the materials, the fittings were delivered over a period of one week, while the pipes were delivered by articulated trucks over a period of 8 weeks. Construction of the pipeline commenced in Ballyheane at Valve House 14. This allowed the construction to continue bringing the water with the pipeline as it was constructed. The pipeline was then tested in 1km sections to a pressure of 14 Bar (200psi).
Progress meetings and reports
Monthly progress meetings are held on site with site staff, Mayo County Council Project management team (Water Services), PJ Tobin Consulting Engineers and Mayo County Council Archaeologists. Construction progress is reviewed and ongoing problems are discussed and resolved. The pipeline is currently being constructed at a rate of 1400m per month and is due to be completed in late 2004, on time and within budget. The progress achieved by the Direct Labour crews compares favourable with progress achieved by contractors constructing similar works throughout the County.It is expected that the Scheme will be commissioned and fully operational by the end of 2004.
Belcarra Group Water Scheme
Construction work on the upgrading of the Belcarra Group Water Scheme is running concurrently with the Lough Mask Scheme. In order to minimise disturbance to the public the Direct Labour crews are constructing the GWS pipelines along the route of the Lough Mask Pipeline. This involves the construction of 4600m of uPVC water distribution mains ranging in size from 100mm to 200mm and over 80 single house connections. This work is coordinated by the Water Services Section of Mayo County Council and Bluehills Consulting Engineers representing the Belcarra GWS.
Valve Houses
Pierse Contracting Ltd. commenced construction of the Valve houses early in 2003 The construction of these valve houses was completed under the Lough Mask Regional Water Supply Scheme, Stage 3, Extension to Knock and Ballyhaunis. These valve houses are now complete and await commissioning once the pipelines are complete.
Archaeology
A team of Archaeologists are on site, and are monitoring the excavations around known archaeological features and investigating possible new archaeological sites. To date a number of new sites have being identified including the possible remains of a church.
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