WORK at Kennington roundabout is set to go over budget by about £1.5m, partly due to the relocation of protected orchids.
Oxfordshire County Council is turning the junction into a “hamburger” roundabout to make traffic flow better.
The scheme – originally due to cost about £6m – will also see traffic flow improved at the Hinksey Hill interchange and the four bridges between Heyford Hill and Hinksey Hill refurbished.
A report to the county council’s cabinet, which meets today, says the increased cost is due to higher than expected subcontractor costs, the relocation of protected orchids, and the use of temporary electronic signs.
The report says the county council had considered redesigning the scheme to make it cost less but has now decided to use funds from underspends and unrequired contingencies from its 2013/14 highways maintenance budget.
Council spokesman Martin Crabtree said: “The main reason for the increase in the cost of the work at Kennington is the delays relating to the water mains diversion work carried out by Thames Water.
“Pyramidal Orchids during the surveying and they were moved before the scheme started to a location nearby, but away from the work.
“The cost of doing this amounted to approximately £6,000, which is a tiny part of the overall scheme cost, but important in ensuring we do not destroy valuable grassland habitat when undertaking the scheme.”
About 60,000 vehicles use the two roundabouts every day and the aim is to increase capacity by 30 per cent during the evening rush hour.
The work is expected to be completed by the end of November, with a six-day working week to get the scheme finished on target.
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