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Letters / Basic maths?

During the last decade, a report called the Shetland Inter Island Transport Study (SIITS) was commissioned jointly between the Scottish Government and the Shetland Islands Council.

Due to concerns I had with some of its content, I sent a letter to our MPs; I was surprised and even more concerned after I received a reply from Transport Scotland, to which I have added in figures from the same SIITS report in brackets, to make it easier to understand.

As indicated, the Scottish Government jointly funded a study by Shetland Islands Council into inter-island transport which considered a fixed link connection to Whalsay as part of the Shetland Inter-Islands Transport Study (SIITS) transport appraisal. The study concluded that a fixed link option be rejected on the basis that the cost, (£1 million per annum) significantly exceeds the expenses associated with on-going ferry services (£3.4 million per annum), even when considered over two ferry replacement cycles (60 years).” 

It would appear according to transport Scotland, that a running cost of £60 million is more expensive than £204 million? 

The SIC ferry replacement term was recently increased from 20 to 30 years, and terminals to 40 years; so the Whalsay ferry service would require five new ferries during 60 years, one ferry now as the present ferry Hendra is ten years beyond its replacement date; the other ferry Linga is 20 years of age, so another would be required in ten years time; further replacements would then be required in 30 and 40 years and another at year 60. 

The Whalsay ferries are run on open waters routes, so there is a requirement for an alternative more sheltered crossing and mainland destination to keep the service running in inclement weather conditions; this requires three new terminals to be built now, as the terminals are all about 10 years beyond their replacement date and those terminals would then be due for replacement again in 40 years time.

The cost of building five new ferries and six new terminals in 60 years for the Whalsay route might well be quite a bit more expensive than the cost of building one tunnel with a life-term of probably 120 years.  

In 2002 a tunnel was proposed in Yell sound for £26.9 million to a worst case cost of £32.5 million.

The councillors, following the advice of their transport department officials, dismissed the tunnel and two ferries and two terminals were built. 

The cost of this ferries project was later revealed by the SIC director of finance to be £37.1 million, when totalled up to 2006; those ferries will be due for replacement in 2034 and the terminals at 2044, that service will now have cost well over £100 million since 2004; the tunnel could have been built and run for less than £50 million during the same period of time. 

The cost of running the larger ferries on the three mile Yell sound route was £5.8 million in 2015/16, the Whalsay route is five to seven miles so running larger new ferries on the Whalsay routes would probably cost quite a bit more than running the Yell sound service.

The SIC revealed in 2021 that the ferries running costs had increased by 40 per cent since 2015/16, this would make the combined Whalsay and Yell sound running costs £12.88 million as a 2021/22 figure. The replacement of those ferry services with tunnels would have more than halved Shetland’s annual ferry service running costs and reduced Shetland’s total carbon footprint by about 30 per cent as a bonus in doing so.

It’s only basic maths that anyone can calculate, with the exception apparently of the consultancy firm and the SIC staff at ZetTrans and Transport Scotland. 

The SIITS documents also contain a report comparing SIC figures for tunnels with a 2017 Norwegian quote for the construction of a Whalsay tunnel, however there is an admission at the end of the report that the tunnel figures they had used in the comparison were flawed – would this then mean that the only valid figure in their whole tunnel report was the Norwegian quote?

Perhaps our new SIC council should consider a change of personnel at ZetTrans and take more care with who they hire as consultants, this would perhaps enable that department to produce more credible reports. 

William Polson
North Park