If Trident is removed from Scotland, what next?

June 2014



Parliament gate image

4  Trident is removed from Scotland, what next?

Long term relocation

28.  The preference for the UK would be for Trident and the necessary facilities to remain in Scotland, as Rt Hon Nick Harvey MP, then Minister for the Armed Forces, told us: “I would have thought that relocation would be just about the least favoured option that it would be possible to conjecture.”[49] And as a result, he said:

The UK Government are not making plans for independence, as I explained, and hence we are not making plans to move the nuclear deterrent or indeed the submarines from HM Naval Base Clyde.[50]

29.  But, as we have seen, in the event of separation and a new Scottish Government insisting upon the ‘speediest safe transition’ of the nuclear fleet from the Clyde, then this could be done in less than twenty four months. If the UK wanted to maintain the nuclear deterrent, then the UK would have to identify and develop an alternative site, or sites, that replicated the assets of Faslane and Coulport. (Faslane and Coulport are two sites, eight miles apart, connected by a road.) We heard differing views as to how easy this would be.


30.  Faslane was chosen because it provided ready access to deep water and space to build a naval base that could be protected. There are other sites where submarines currently berth, or could be adapted to provide a home for the Vanguard submarines. Francis Tusa suggested Barrow, where BAE are currently building the Astute-class submarines, as it had support facilities, included a ship-lift, similar to Faslane. The main issues with Barrow is the shallow approach, that would restrict submarine access to convenient monthly tides without significant dredging, and the size of the dock which would not, at present, have room for more than two Vanguard-class submarines.[51] Milford Haven does provide access to very deep water, and it would have more room than at Barrow for docking,[52] but it was passed over in the 1960s and there are important economic and industrial facilities there today that would make it less suitable.[53]

31.  Devonport appeared to be the most popular, it had been the former base to the Trafalgar-class submarines and the Vanguard-class submarines regularly visit Devonport (unarmed) for maintenance, but as with the other possibilities, the main issues with Devonport did not relate to recreating the facilities of Faslane, but of Coulport, and without Coulport, there is no deterrent.[54]


32.  Malcolm Chalmers, who had recently reviewed the original options for Polaris in the 1960s, concluded that given time and expense, Devonport might work for Faslane but:

You could not put the Coulport facility in Devonport because there simply is not the room given the safety margins, which would be higher now than they were in the 1960s.[55]

33.  Coulport is not just a storage site, but also possesses the huge floating dock where the warheads are placed inside the missiles, three kilometres from Garelochhead on one side and Ardentinny on the other.[56] Any new warhead storage facility would need to provide safety assurances on a similar scale in relation to loading and offloading warheads from the missiles in the submarines.[57] To do so, such a site would preferably be near the submarine base and on the coast, as Professor Walker said:

In my view, the warhead storage is not the crucial issue; the crucial question is how you create a facility where you can marry the warhead and missile, load it on to the submarine and also remove it from the submarine, if you need to, and bring it back on shore. That is a very delicate and dangerous operation, so it is all to do with safety calculations. […] You don’t want to do anything like this near built-up areas, tourist sites or whatever.[58]

34.  Barrow and Devonport have a large population too close to satisfy the safety margins required, and Milford Haven has a huge Liquid Natural Gas facility nearby. Falmouth, relatively close to Devonport, had been considered as a possible Coulport in the 1960s, but was ruled out because it would impact upon an area with a strong tourist economy and involve the loss of two villages and moving a significant population.[59] Portland, which was considered in the 1960s, was judged to not have a suitable site for the warheads depot closer than a Ministry of Defence tank range 15 kilometres inland.[60] Professor Chalmers said this criteria of keeping warheads and missiles far enough away from people and sites of economic value was why Scottish locations were popular among the 1960s options:

A lot of the issues at that time, which would be greatly intensified today, would be in relation to the safety margins that the Nuclear Installations Inspectorate would insist on. Unless you are prepared to re-house a very large number of civilians and close down areas of housing and so on, it limits where you can put the particular facilities.[61]

35.  Some, such as John Ainslie, of CND Scotland, said it would not be possible to find a new site,[62] although he accepted that there may be sites additional to those considered in the 1960s.[63] Others, such as Francis Tusa, editor of Defence Analysis, believed that the problems of relocation had been exaggerated. He pointed out that Coulport had been designed to accommodate between 500 to 600 warheads, whereas any new facility would only need to store around 200 and could be considerably smaller. He suggested moving the warheads to a modernised AWE Burghfield or AWE Aldermaston, which both already had full nuclear licences.[64] Malcolm Chalmers said Aldermaston was not relevant because it was not on the coast,[65] and Mr Tusa conceded that it was not ideal to have the warheads in the middle of Berkshire and the submarines based in Devonport but “it does not mean you cannot do it.” He agreed this would not happen quickly but: “there are more than enough nuclear facilities all round the remaining parts of the UK” and it was “just an article of faith that you can never move any of the boats anywhere; none of the facilities could be replicated anywhere else, and it would all take far too long.”[66]


36.  We found it difficult to establish what it would cost to replicate Faslane and Coulport elsewhere. Most witnesses, such as Professor Walker, thought the cost would be huge:

Don’t ask me to put a figure on it; I have no idea at all, but certainly it would be billions of pounds.[67]

37.  In contrast, Francis Tusa thought that finding a new home would not be too expensive:

the number of options for moving the deterrent out of Scotland is huge, and a lot of them are not that expensive either. I have seen reports that it would cost £50 billion to move. No, it would not; it really wouldn’t.”[68]

38.  When we asked the Ministry of Defence if they knew how much it would cost, Nick Harvey MP, then Minister for Armed Forces, said: “It would be a very challenging project, which would take a very long time to complete and would cost a gargantuan sum of money”[69] He told us that a recent upgrade of the facilities at Faslane had cost £3.5 billion and “If we were to replicate it somewhere else, that figure would be dwarfed by whatever that would cost”[70]

39.  Nick Harvey MP emphasised that the price of forcing the nuclear deterrent out of Scotland would not be seen in isolation:

In the context of that pan-governmental negotiation to which I alluded earlier, which I would expect the Treasury to take an active interest in, if a future independent Scottish Government were to insist upon the nuclear deterrent being relocated out of Faslane, the impact of that on that pan-governmental discussion would be very substantial indeed. It is hard to think of any single item that would be larger in that negotiation.[71]

And the price would not be borne by just the residual United Kingdom:

if that cost had to be met in a way which, in a practical sense, would seem to me and I would have thought seemed to people of good sense to be completely unnecessary, then there would be an implication of that across the rest of the negotiation. It would be the largest item looming across the whole piece. […] If the residual UK taxpayer had to pick up that bill, their ability to pick up any other bills would be proportionately diminished.[72]


40.  Similarly, it was difficult to find a consensus on how long it would take to build a new version of Faslane and Coulport. It took three and a half to four years to build Coulport,[73] but most of our witnesses thought the process of building a new version would take much longer, not least because the political issues around any new site would lead to unpredictable delays. As Professor Walker pointed out:

None of these facilities had to go through any kind of planning system. The public feels it has a right to express an opinion on these matters, and I can imagine it being very controversial […] The Government would have to go through various quite difficult political processes to try to get consent for this.[74]

Professor Malcolm Chalmers agreed:

For people at Falmouth at the moment, having a nuclear weapons facility in their back yard is not right at the top of their agenda, and it would be in this scenario. I think it would take a very long time to work through. It is very uncertain where it would all end.[75]

41.  As a result, Professor Walker thought it might take twenty years or longer:

Yes, but 20 years might be a minimum; it might be longer than that. You would have to sustain your political will and funding for a very long time. I don’t know whether the political parties could agree upon that and exactly what the ramifications would be. The process of finding a site might take five to 10 years, and then being sure you have one, and all the engineering and construction works, mean it could be a long time.[76]

42.  Dr O’Brien thought it might be completed in fewer than twenty years, possibly 10 or 15, but only with an enormous amount of resources, no objections and cross-party support, and even then he thought it unlikely.[77]

43.  Peter Luff MP, then Parliamentary Under Secretary of State for Defence, said that while he could not say how long it would take to relocate Faslane and Coulport, he described some of the construction complexities at the present site:

Nevertheless, one has to recognise that one is moving nuclear-qualified facilities and the standard of safety required is absolutely enormous. Even quite simple engineering tasks for a conventional boat/ship become immensely more complicated when dealing with nuclear facilities. I am going to Faslane to see the new jetties being constructed. It is a saga in itself. One jetty has been a huge struggle. There are massive problems with the contractor meeting the very testing requirements of a nuclear-qualified facility. It is not just a question of shoving up a few buildings. It is a question of creating an immensely strong infrastructure against any seismic shock, for example, that you can possibly foresee. The orders of magnitude for the construction complexity are significantly greater than any other more routine defence investment. Therefore, I have no reason to challenge the figure you are giving but I cannot justify it either. They are much longer periods of time than are normal for construction projects.[78]

44.  He agreed that there would have to be a period of consultation for any new site, and that: “It would be a very long project indeed. It could not happen in a couple of years.”[79] In view of this, we asked the Government if they had held discussions with the Scottish Government about whether Trident would have to be removed from the Clyde immediately. Nick Harvey and Peter Luff agreed the Ministry of Defence had not been approached or had discussions with the Scottish Government about defence matters in the event of Scotland becoming a separate country, and Mr Harvey added:

I find it quite impossible to make an assessment of their intentions. One can piece together different statements that have been made at different times. One understands that the policy position of the SNP has historically been that they are completely opposed to the nuclear deterrent, but I do not know what their precise proposition will be when making the case for independence.[80]

45.  Identifying and recreating a suitable base to replace Faslane and Coulport would be highly problematic, very expensive, and fraught with political difficulties. In particular, it would be difficult to find a site that satisfied the requirements for the co-location of the submarine base, the warheads depot and the facility to marry the warheads and missiles on to submarines that adhered to the safety requirements.

46.  We were told that the Ministry of Defence was not making contingency plans for the event of Scotland becoming a separate country. Estimates suggest it could take up to twenty years or longer to develop a long-term replacement for Coulport. It is possible that the clock on relocating Trident would not start until after the result of the referendum is known.

47.  The Minister for the Armed Forces has said that if a newly separate Scotland insisted upon the removal of Trident out of Faslane, and the UK was forced into developing a new base at great expense, then the associated costs would be included in the separation negotiations.

Alternatives outside England and Wales 


48.  It has also been suggested that the warheads might be stored and loaded onto the submarines at a base outside the British Isles, if only as a temporary measure. Two options had been suggested: the French facilities in Brittany or the US facilities in Georgia.[81] Indeed, Alex Salmond MSP, has said that following separation, the UK would have two choices: relocate to another part of the UK or use bases in America or France.[82] Francis Tusa thought the US or France options could work:

Is there any reason why we should not be able to store warheads in French facilities off Brest? We shared American storage facilities for nuclear warheads at Iserlohn for 40 years and no one seemed to care. […] There were American, German and British guards. The UK had British bunkers on German soil, but it was a US sovereign base. I did not notice anyone caring one way or the other.[83]

49.  Professor Malcolm Chalmers told us he did not think using the US was an option because it would raise questions about how independent the UK’s deterrent was:

The option of having the Coulport facility in the United States was looked at when Trident was first purchased. I think part of the reason it was rejected was that it was seen as just a step too far to being perceived as not having an independent deterrent if both your missile servicing and warheads were based in the United States. It would have saved money. There was also an issue at that time, which was not fully explored, as to whether the United States would be prepared to have a foreign nuclear weapons base on its territory or whether it would ask, “If you are not even prepared to have your nuclear servicing done in your own country, how serious are you about having an independent deterrent?”[84]

He also considered the French option unlikely:

I think that in the case of France it would be a different dynamic. There may be a stronger French stake in Britain remaining a nuclear weapons state than there is an American stake in that, but, even then, it would not be automatic that the French would be prepared to have a sovereign foreign nuclear weapons base on their territory. They would think twice about it. It is possible; I think it is an option, but I think it would be a difficult one.[85]

50.  John Ainslie said that the UK submarine fleet probably could not be accommodated in France; the current base at Ile-Longue would be too small to accommodate the additional UK submarines so would require building a new base, which would take time, and be exacerbated by all the political problems that would flow from a foreign power building a new base on French soil.[86] Indeed, Peter Luff MP admitted that while the UK does collaborate with the French on nuclear and security issues: “The idea of dumping off the boats there for a few years while we sort out a long-term solution would be a little tricky to manage.”[87]


51.  An agreement between the UK and Scottish Governments to keep Faslane and Coulport as a UK base within a separate Scotland would save the costs and inconvenience of relocation. Dr O’Brien thought the issue was not whether a deal could be negotiated but whether any agreement could be managed on a day-to-day basis:

You can cut a deal that, yes, you can use the base, but that opens up a huge number of other questions: how long, how you protect it, and what if there are protestors. To my mind, it is a little more involved than just saying, “You pay; you use.”[88]

52.  The agreement would need to address how UK submarines might pass through Scottish waters, how the current convoys to AWE Burghfield would continue across Scotland, and how it would manage the geographical fact that Faslane and Coulport are eight miles apart, and including the connecting road in a UK sovereign base would cut Garelochhead and the Rosneath peninsula off from the rest of Scotland.[89] William Walker explained some of the problems relating to ensuring access to the sea:

Under the Law of the Sea, territorial waters extend for 12 miles. Essentially, that means 24 miles, which takes you south of Arran. Am I right in remembering that, under article 20 of the Law of the Sea, any foreign submarines have to fly a flag and be on the surface when travelling through territorial waters? There is an issue there. Would the Scottish Government be at all times informed of the movement of submarines up and down these channels? I imagine there would have to be a separate treaty between the two as to exactly how these waterways will be managed. There is also sonar equipment and many other things to do with this, which I imagine are very sensitive matters for the UK Government, but all of this would have to be part of a treaty between the two as to exactly how these waterways were managed.[90]

He thought this would provide problems for both governments, not least how to police the area if anti-nuclear protests continued:

I have always felt that, if the UK Government look at a situation of having their strategic nuclear force in this particular place in a foreign country, they will feel extremely uncomfortable and will wonder how to manage it, what the international implications are, and how to react to exactly what you are suggesting—the idea that you might have public protests happening there and so on. You might have an accident in the Clyde. How exactly do they respond to this? I think they would feel very uncomfortable.[91]

53.  John Ainslie, CND Scotland, did not think a sovereign base was tenable:

If the force is based in Scotland, and if we are looking at the scenario of an independent Scotland, which is a separate, sovereign state, the idea of a sovereign state having its whole nuclear weapons capability indefinitely in another sovereign state is probably not sustainable.[92]

54.  Neither did Professor Walker think a sovereign base, secured by a treaty, was likely.[93] He said the idea of a sovereign base was an outdated concept, and thought it more likely that the land remained Scottish sovereign territory with a long lease to the UK, managed by a formalised gentlemen’s agreement between the two countries.[94] If this was the case, then Dr O’Brien said the nature of any agreement depended on the NATO question:

If Scotland were a NATO ally, you might be able to work up an agreement, but so much of this hinges on the NATO question. If Scotland remained in NATO, you could perhaps limit it and give Scotland, as a NATO ally, certain defensive responsibilities without it. A non-NATO Scotland would mean they [the UK] would want a fully protected area.[95]

55.  The Americans previously had a submarine base on the Holy Loch, and at the time the UK had provided secure access to the sea. This was workable because the agreement between the US and the UK was made within a formal alliance. With that in mind, Dr O’Brien said:

Personally, I don’t see how a nuclear power can, in the long term, base its weapons in another country, particularly if it is done by gentleman’s agreement that could be changed because of domestic political changes in that country. Scotland could go down another route. I could see that as being the best short-term—even medium-term—solution, but not in the long term.[96]

56.  The UK’s preferred option is for nothing to change. Failing that, the next best option would be securing an agreement that enabled the submarines to operate out of Faslane until an alternative base was found elsewhere. Doing so, without the status of a sovereign base, appears to be at odds with what Nick Harvey MP told us, that if the UK Government could negotiate for the base to remain in some form, then it would consider it “critical” to have “complete freedom of action—complete control and complete sovereignty over the facility.”[97] And, while not speculating on contingency plans that the MoD were not making, he said: “the critical point of principle would have to be complete control over what we did there.”[98] Would a newly separate Scottish Government be willing to facilitate and guarantee this? Allowing the base to remain would seem unlikely, as Alex Salmond told the BBC that while it was for the UK Government to decide what to do with Trident once it was removed from Scotland:

That doesn’t mean we think it reasonable to lease out part of Scottish territory to what you describe as a Cyprus situation. If Scotland, by majority, doesn’t want nuclear weapons, the SNP proposition is to write that into the constitution of the state. So that would make the possession of nuclear weapons illegal.”[99]


57.  The advantage of the UK having continued use of Faslane and Coulport would mean Vanguard-class submarines could continue to operate out of the Clyde while the MoD identified and developed an alternative base for the Successor submarines.[100] Professor Walker suggested this might enable CASD to continue:

If it is a question of the replacement submarines going somewhere else and you are building up a replacement fleet in other bases, you can manage the transition so that you phase out an old submarine and bring in a new one, although it is located elsewhere. I can imagine it working. If you are doing it rather suddenly and rapidly, it is hard to imagine. There would be periods in which there was no deterrent operating in those circumstances but, again, it is a matter of how it is phased and managed. You could imagine it working; in other scenarios it wouldn’t work.[101]

58.  Even such an agreement could be reached on a phased transition, this would necessitate the Scottish Government agreeing to a timetable that could mean nuclear weapons remaining at Faslane for at least another twenty years. Malcolm Chalmers said that this could work in Scotland’s favour in the separation negotiations:

If a Scottish Government were to accept that for a significant period of time, perhaps indefinitely but certainly a long period of time, Trident would have to remain because there simply is not anywhere else to put it, that in itself would be a significant bargaining card for Scotland. Scotland could say, “We’ve given you this, but in return we want a reasonable negotiation that leaves Scotland with a defence force that is small but does the job, and a Scotland in NATO that therefore does not have to rely entirely on itself for its own security.”[102]

This last point is important. The SNP have said that they would like to co-operate with the UK on some military matters. The UK is highly unlikely to co-operate if Scotland is not willing to co-operate on Trident.

59.  If there was co-operation, then the UK might avoid temporary loss of CASD, but it would not avoid the costs of relocation. It would still require the UK to build a new base, it would still cost a large amount of money, and it would mean nuclear submarines carrying armed Trident missiles operating out of Scotland for possibly another twenty years. There would be a transition period where the UK would be operating two bases simultaneously: one for Vanguard in Scotland, possibly until 2028, and one for Successor in England or Wales. The running costs for operating Faslane and Coulport alone are an estimated £2 billion a year,[103] and there is a risk that the combined cost of replacing Trident and developing a new base may be incompatible with maintaining the deterrent in the future.[104]

60.  Any agreement whether to relocate the UK nuclear deterrent outside the British Isles, possibly in France or the USA, would be a decision for the UK in discussion with its allies. However, the evidence presented to us suggested this would be very difficult, both logistically and politically.

61.  An arrangement to allow the UK to continue to operate Trident out of the Clyde in a separate Scotland could be negotiated in theory but it would be very difficult in practice. The Scottish Government would need to agree to the UK retaining complete freedom of action, either as a sovereign base in Scotland or some sort of lease arrangement. The agreement would have to assure the UK Government that the Scottish Government would cooperate sufficiently to ensure the base could operate on a day to day basis. A political deal or a gentlemen’s agreement would be vulnerable to a change of government and withdrawal of cooperation. Any agreement would have to be formalised.

62.  An agreement allowing Trident to remain on the Clyde would enable the UK to continue to operate Continuous At Sea Deterrent. Such an agreement could be to allow Trident to remain indefinitely, or allow time for the UK to develop a new base elsewhere in England or Wales for the new Successor submarines.

63.  A separate Scotland would be presented with a choice over Trident. It could honour the long held policy of the SNP that there should be no nuclear weapons in Scotland and insist the ‘speediest safe transition’ of Trident from Scotland, which can be done within twenty four months. In fact, Trident can be deactivated within a matter of days. The process requires the Vanguard submarines to come off patrol, the UK would lose the ability to operate its nuclear deterrent and inevitably create the prospect of unilateral nuclear disarmament being imposed upon the Royal Navy and UK Government, since the construction of facilities elsewhere could take upwards of 20 years.

64.  Alternatively, a separate Scotland could, in cooperation with the UK, allow Trident to remain on the Clyde long enough for the UK to identify and develop a new base elsewhere. This would mean armed nuclear submarines operating out of Scotland for 20 years or longer. Developing a new base, particularly replicating the facilities at Coulport, could only be done at great expense, and the UK Government has made it clear that any such costs would be included in the separation negotiations. This would be alongside other items such as retaining the Bank of England as a lender of last resort and financial regulator for Scotland, or access to intelligence and the work of GCHQ.