Publication - FOI/EIR release

Transport Scotland salt usage on roads, costs and alternatives: EIR release

Published: 15 May 2019
Topic: Public sector, Transport
FOI reference: FOI/19/01147
Date received: 25 April 2019
Date responded: 14 May 2019

Information request and response under the Environmental Information (Scotland) Regulations 2004.

Information requested

Salt usage on roads in Scotland.

1. How much salt is used annually?

2. How much does road salt cost?

3. Are supplies secure?

4. Have you looked at any alternatives to rock salt?

5. Do you have any details on the brine study that you conducted and what type of brine did you use?

Response

As the information you have requested is ‘environmental information’ for the purposes of the Environmental Information (Scotland) Regulations 2004 (EIRs), we are required to deal with your request under those Regulations. We are applying the exemption at section 39(2) of the Freedom of Information (Scotland) Act 2002 (FOISA), so that we do not also have to deal with your request under FOISA.

This exemption is subject to the ‘public interest test’. Therefore, taking account of all the circumstances of this case, we have considered if the public interest in disclosing the information outweighs the public interest in applying the exemption. We have found that, on balance, the public interest lies in favour of upholding the exemption, because there is no public interest in dealing with the same request under two different regimes. This is essentially a technical point and has no material effect on the outcome of your request.

1. This varies year on year depending on the severity of the winter.

Salt usage figures from 2010-2018 are detailed below:

2010/11 – 645,000 tonnes
2011/12 – 425,000 tonnes
2012/13 – 691,000 tonnes
2013/14 – 335,600 tonnes
2014/15 - 563,200 tonnes
2015/16 – 391,000 tonnes
2016/17 – 335,000 tonnes
2017/18 – 740,000 tonnes
*2018/19 – 354,000 tonnes (*Transport Scotland’s winter season does not end until 15 May and these are figures to 7 May 2019)

Salt stocks are fundamental to a successful winter on our roads and national salt figures are published on Transport Scotland’s website: https://www.transport.gov.scot/publication/salt-group-situation-report/

2. While our aim is to provide information whenever possible, in this instance the Scottish Government does not have the information you have requested. Therefore we are refusing your request under the exception at regulation 10(4)(a) of the EIRs. The reasons why that exception applies is that the amount spent on salt is not held by Transport Scotland. Furthermore, the payment mechanism for the provision of winter service through our Operating Company contracts is a fixed ‘monthly sum’. This includes the procurement of salt, winter fleet and equipment for use on our trunk roads. The cost of salt alone cannot be disaggregated from the lump sum.

3. The Scottish Salt Group (SSG) was established during the severe winter conditions early in 2010. The Scottish Salt Group monitored the restocking process throughout the summer of 2018 and met with suppliers to confirm there was adequate salt production to meet the demand and that restocking targets for Scotland were being met. Following the salt shortage of 2010-11, strategic salt was purchased (in addition to operational salt) and this is managed by the Scottish Salt Group.

4. We have promoted research into the durability of liquid brine through the National Winter Service Research Group (NWSRG). Further details can be found on our website: https://www.transport.gov.scot/our-approach/keep-scotland-moving/winter-service/#42971

5. We have completed research into sodium chloride brine treatments over the past 5 winter seasons. During the 2018/19 winter season, our Operating Company in the North-West again utilised the latest combination spreader from Germany on the A835 to undertake sodium chloride brine treatments through the winter period. Early indications are the results have again been a success; albeit with limitations for snow events.

Full reports of our studies are contained within Annex A – D as attached.

Sodium chloride brine has been used in all our trials.

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