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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.
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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
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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