03 December 2008

Sunderland council decide way forward for River Wear crossing

Today, Sunderland City Council's cabinet are meeting to agree the way forward for their iconic bridge scheme (iconic is a much abused term in bridge design, but this is one bridge that if it is ever built, will undoubtedly merit the description).

The Sunderland Echo recently reported that the current Spence / Techniker concept design (pictured) "will have to go out to tender to engineering companies. Experts will then come up with a working design and accurate costings for the structure to see if it will work and be affordable." The Happy Pontist previously wondered whether the current designers might not be too happy to see their work passed on to another firm i.e. the un-named experts.

It seems the Echo's report was slightly misleading; the council's actual intention is to appoint Techniker to develop their own design further. In a report to the council cabinet (available online [PDF]), the council officers recommend appointing Techniker to "continue with the development of the concept design up to a stage where sufficient confidence on cost, risk and buildability can be provided to assess its affordability". No doubt Techniker will be pleased to take back the lead role on this bridge at long last.

The council are definitely taking the risks associated with this highly unconventional design seriously - their report acknowledges it to be "innovative and unique", stating that "a bridge of this type and scale has not been built anywhere else". They want to achieve a comparative level of cost certainty to a conventional bridge, which will require a very substantial amount of design work indeed.

The report discusses the extra £30m required for the iconic bridge (over and above the cost of a conventional bridge), but since it doesn't split out the cost of the bridge from the cost of the wider Sunderland Strategic Transport Corridor scheme (of which it forms part), it's difficult to comment on how reasonable their estimates are. By my estimate, £30m works out at about an extra £3,000 per square metre of deck.

Techniker's designer Matthew Wells has previously suggested that a bridge "of similar size and span and of exactly the same construction and arrangement has been constructed a decade ago without any difficult[y] or on-cost or excessive maintenance regime", so perhaps this will now be an opportunity to tell everyone what that bridge is and use it as a cost benchmark. Perhaps Calatrava's Alamillo Bridge is the best comparison: it cost US$38m when built in 1992, and allowing for inflation that would work out at roughly £5,000 per square metre of deck today. However, the River Wear design is substantially more exotic than even Alamillo, so any benchmark may be futile.

The council report also discusses the recent public consultation. Newspaper polls found over 90% in favour of the Techniker design. However, the council's own consultation finds that only 52% of people were in favour of "a striking design", against 49% wanting something "tried and tested". So with half of Sunderland opposed to the bridge, you must wonder exactly why their council is quite so keen to pursue it.

I sometimes feel as if the River Wear story has taken over this blog (notwithstanding exciting side trips to the Alps), but it undoubtedly has a long way to go yet!

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