Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Infrastructure Services Item: 00 Page: 1 REPORT TO THE BANFF AND BUCHAN AREA COMMITTEE 22 MAY 2012 REPLACEMENT OF TILLYNAUGHT BRIDGE 1 Recommendations 1.1 It is recommended that the Committee:1. accepts the lowest tender of £485,699.47 submitted by R J McLeod (Contractors) Ltd for the main contract to construct a new bridge at Tillynaught, incorporating a proprietary prefabricated road bridge deck already procured separately from Mabey Bridge Ltd. 2 Background/Discussion 2.1 Tillynaught Bridge carries the C27L Culphin to Dykehead Road over the Burn of Boyne. The bridge was badly damaged by an extreme river spate on 1st November 2009 and subsequently collapsed on 10 th November 2009. The C27L road has been closed to vehicles and pedestrians since the collapse. 2.2 The replacement road bridge proposal was approved by the Banff & Buchan Area Committee on 16 February 2010 and Infrastructure Service Committee on 18 March 2010 subject to there being appropriate capital plan funding available. 2.3 The Policy and Resources Committee of 15 September 2011 agreed to accept an offer received from Mabey Bridge Ltd for the supply and erection of a proprietary prefabricated road bridge deck at a tendered sum of £132,800. Currently work on fabrication of the road deck is progressing off site, to be ready for erection on completion of bridge end supports, which are to be constructed as part of the main contract. 2.4 The Works covered by the main contract for which this tender approval relates comprises the design and construction of piled foundations, the construction of reinforced concrete bridge end supports and approach walls, associated roadworks and earthworks, river training works, safety fencing and finishing. 2.5 The Head of Finance and the Monitoring Officer within Corporate Services have been consulted and are in agreement with the contents of this report. Infrastructure Services Item: 00 Page: 2 3 Staffing and Financial Implications 3.1 There are no specific staffing implications arising from the report. 3.2 Tender documents were issued to the following contractors (in alphabetical order): Aberdeenshire Council Operations Balfour Beatty Civil Engineering Ltd Chap Construction Aberdeen Ltd George Leslie Ltd Hunter Construction (Aberdeen) Ltd RJ McLeod (Contractors) Ltd 4 tenders were submitted by the due date for tender return. Tender sums (in ascending order) for the Works were: Submitted Tender £485,459.47 £511,197.19 £538,360.18 £561,563.00 Corrected Tender £485,699.47 £511,565.19 £538,360.46 £562,841.82 The lowest tender, in the amount of £485,699.47 was submitted by R J McLeod (Contractors) Ltd. It has been assessed and is considered to be a competent tender, free from qualifications and with reasonable rates. 3.3 The new estimated Total Scheme Cost for the replacement Tillynaught bridge is £789,755 Of this sum, £147,442 has been spent in previous financial years (up to end March 2012) on design and in procuring the steel to permit fabrication of the proprietary bridge deck. The remainder of the estimated Total Scheme Cost (£642,313), which includes for site supervision, utility diversions and the remaining amount due to Mabey Bridge Ltd for supply and erection of the proprietary bridge deck, shall be met from the £2,770,000 allocated in the current Capital Plan (Bridges and Structures Line) for 2012/2013, as approved by Policy and Resources Committee on 19 April 2012. 3.4 A report to the Infrastructure Services Committee on 3rd December 2009 gave a budget estimate for the works of £1,300,000. The subsequent option appraisal report to the Banff and Buchan Area Committee of 16th February 2010, gave a Total Scheme Cost of £555,000 for a 10m span bridge. The increase in the estimated Total Scheme Cost is in the main due to two factors. These are (1) increase in span of the bridge from 10m to 18m required to improve the waterway area, and (2) amendment of the foundations to include deep Infrastructure Services Item: 00 Page: 3 piling and sheet piling due to the very poor nature of the ground conditions and the presence of an aquifer. Given the substantial nature of the original bridge and the lack of cracking/subsidence, such poor ground conditions would not have been considered likely. 3.5 The effect on the Capital budget will be managed by prioritising remaining projects. Throughout the year there is a monitor of progress and spend for all projects; inevitably issues arise out with our control which require a reprioritisation. Included in the current list are projects generated from asset management where early intervention is used to minimise future spending. These will be reviewed with a view to moving them into future years where appropriate. Philip D McKay Head of Roads and Landscape Services Report prepared by: Donald Macpherson, Structures Manager Report date: 20 April 2012