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You are here: BAILII >> Databases >> Scottish Court of Session Decisions >> Shetland Islands Council, Re Application for Judicial Review  ScotCS CSOH_5 (12 January 2007)
Cite as:  ScotCS CSOH_5,  CSOH 5
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OUTER HOUSE, COURT OF SESSION
 CSOH 05
OPINION OF LORD REED
in the petition of
Judicial Review of a decision by LERWICK PORT AUTHORITY
 One of the finest natural harbours of the British Isles lies in the Sound of Bressay in Shetland, between Mainland, the largest of the Shetland Islands, and Bressay, a smaller island to the east. The harbour has provided a safe anchorage for centuries, and is the reason for the development of Lerwick, the principal settlement of Shetland, on the Mainland side of the harbour.
is a fishing port, a centre of marine support for the offshore oil and gas
industry, a ferry port with services to other ports in the
the present proceedings Shetland Islands Council (the petitioners), who are the
local authority, seek judicial review of a decision by Lerwick Port Authority
(the respondents) to revise their dredging proposals for the navigation channel
 At the commencement of the first hearing, however, the court was invited on behalf of the petitioners to dismiss the petition so far as directed against the Scottish Ministers. During the course of the first hearing, the court was also informed that the complaint concerning the alleged failure to carry out an environmental assessment was not being insisted in; nor was the case based on personal bar; nor was the case based on an alleged failure to comply with the 1974 Order. The challenge to the reasonableness of the respondents' proposals was also qualified in the course of the hearing, as explained below, so as to be predicated on the proposals being, in the first place, contrary to the petitioners' legitimate expectation.
 In these circumstances, the petitioners seek two orders, which can be summarised as follows: first, reduction of the respondents' decision to revise their dredging proposals; and secondly, interdict against the respondents from dredging the North Harbour in implementation of their revised dredging proposals, insofar as such dredging would take place outside the limits of the dredged channel originally proposed, as indicated on a drawing provided to the petitioners on 9 January 2004 by the respondents' consultant civil engineers, Arch Henderson & Partners ("Arch Henderson"), until a final decision in respect of the petitioners' bridge proposal has been taken under the Roads (Scotland) Act 1984 ("the 1984 Act").
 At the conclusion of the first hearing, parties lodged a joint minute  in terms of which they agreed, in effect, that the matter to be determined at the first hearing was the petitioners' contention that they have a legitimate expectation that the respondents will not depart from their original dredging proposals. Counsel explained that the parties were agreed that the existence of a legitimate expectation (by which, it was agreed, they meant a substantive legitimate expectation) included, in this case, not only a representation on which it was reasonable to rely, but also detrimental reliance. The question whether the respondents' decision to proceed with revised proposals, despite any legitimate expectation and any detrimental reliance, was unreasonable and ultra vires, or whether the public interest might justify the respondents' failing to fulfil any expectation which they might have created, was to be left over to a second hearing, if necessary. The reason for splitting the issues in that way is explained below: in short, it is because the parties were agreed that the question whether the petitioners had acted in reliance upon a legitimate expectation should be determined at the present stage, on the basis of the material presently before the court, whereas issues of fact had been raised by the petitioners during the hearing, relating to the reasonableness of the respondents' revised proposals, which were not yet focused in the pleadings, and which might require the leading of evidence in some form.
 The parties also agreed in the joint minute that, in approaching the matters to be determined at the first hearing, the court should proceed on the basis of the pleadings and submissions of parties, two joint minutes (agreeing certain matters of fact) which had been lodged during the hearing [15 and 17A], and the documents referred to in counsel's submissions. It was also agreed that the documents were what they bore to be and were an accurate record of any statements which they recorded. It was further agreed that the court should repel the petitioners' pleas relating to personal bar, to the 1974 Order, and to EC law. So far as the two remaining pleas were concerned, it was agreed that the court should determine the petitioners' plea in respect of legitimate expectation. It was accepted by counsel for the petitioners in the course of the argument that, if that plea were repelled, the petition should be refused. If the plea were sustained, the court should deal at a second hearing with the plea of unreasonableness.
 Finally, by way of introduction, I note that this is the second of three related applications for judicial review. As explained below, in 2005 the court granted an application by the present respondents for judicial review of the Scottish Ministers' decision not to "call in", under planning legislation, the present petitioners' notice of intention to develop the bridge. That decision was quashed by the court. Having reconsidered the matter, the Scottish Ministers took the same decision in 2006. An application by the present respondents for judicial review of that decision has not yet been heard.
The factual background
 As a natural harbour with both a north and south entrance,
 In 1997 the petitioners decided to investigate the possibility
of replacing the Lerwick to Bressay ferry with a fixed link [7/10]. In December 1998 they instructed Halcrow
Crouch ("Halcrow"), consulting engineers, to undertake a feasibility
study. Halcrow were to investigate
locations at Greenhead, Point of Scotland and
 Halcrow noted that, at Point of Scotland, the navigation channel was approximately 95 metres wide and was close to the centre of the waterway. The water was relatively shallow, shelving from the shoreline on both sides to 5 metres below chart datum (‑5m CD) at the edge of the navigation channel. The navigation channel was dredged to -6m CD, but the respondents had stated that it was their intention to dredge the channel to -7.5m CD at some date in the future.
 In relation to navigational clearance, Halcrow noted that, although the navigational channel at all the sites under consideration was around 100m wide, a greater clear width would be required at Point of Scotland if a bridge were to be located there:
"A potential problem with the Point of Scotland crossing raised by the Harbour Trust [i.e. the respondents] was that vessels entering the harbour through the north channel have to swing sharply at this location to avoid the middle ground [an area of shallow water to the south of the channel] and berth at the Gremista Quay or other harbour berths. This manoeuvring therefore has a bearing on the clear width of channel required between supports and the Harbour Trust have requested that a clear width of 150m be provided" [para 3.5].
Halcrow observed that it might be worthwhile to undertake ship simulation studies for a design vessel (i.e. a vessel selected as suitable for the purpose of designing the bridge), to determine the minimum clear width required [para 4.1.2]. Halcrow also noted that their instructions required them to assume a vertical clearance from high water level to the soffit of any bridge of 40m [para 3.5].
 In relation to the figure of 150m, I was informed by counsel for the respondents that the respondents had no recollection of that figure being mentioned, although a figure of 160m had been discussed. Since all the other documents refer to a figure of 160m, as explained below, it may be that the figure of 150m was a mistake. Whether the figure was 150m or 160m is not in any event important.
 Halcrow considered a number of options for bridges or tunnels at the three locations in question. Drawings for box girder bridges at Point of Scotland were provided for three possible main spans: 125m, 160m and 260m. It is apparent from the drawing of the bridge with the 160m main span that the measurement of 160m was not the clear width of channel between the central piers, but was measured between the centres of the piers. Since the report envisaged that the piers would be supported on reinforced concrete caissons with abutments (which would sit on the seabed and would extend upwards to a level above high water springs) [paras 4.1.2 and 5.2], the clear width would be significantly less than 160m.
"The choice of bridge option will ultimately depend on the navigation clearances agreed with the relevant authorities."
 In the light of the report, the petitioners decided that
further studies should be undertaken, including an assessment of the views of interested
"This matter was again considered by Lerwick Port Authority Board Members at their meeting yesterday and they asked me to inform you of their observations at this time.
· The proposed air draught of 40m minimum in the main span above Mean High Water Springs is acceptable.
· The main span of the bridge should have at least 160m clearance. This is in the interests of marine safety to avoid as far as possible risk to shipping with ensuing injury or loss of life, damage to vessels and serious environmental damage to our clean environment.
It is pointed out that from time to time large vessels or disabled vessels enter the harbour from the north. To do so they are accompanied by tugs - one at either end. To turn or manoeuvre a 'dead ship', it is necessary for the tugs to swing away from the direction of the forward movement and to do so obviously manoeuvring space is required.
It is also pointed out that in order to protect the Port Authority's right to dredge the north channel to a deeper level, it will be necessary to have at least 160m clear width so as not to disturb the integrity of the supporting piers" [7/44].
In the light of subsequent events, it is important to note that the respondents requested "at least 160m clearance": the minimum distance of 160m would therefore be measured between the inner faces of the bridge structure, rather than being measured between the centres of the piers.
 The report stated that it was intended to
conclude the feasibility study. It noted
that the first part of the study had been a technical appraisal of the various
options. That had concluded that the
best option would be a bridge between Heogan and Point of Scotland, which could
be built for about £15m. The second part
of the study had been an appraisal of social and economic issues. The report noted that there was provision in
the current capital programme of £15m to build the bridge between 2003/04 and
2006/7. It concluded that the proposal
had been thoroughly studied. It
recommended that the Resources Committee should recommend that the council
approve in principle that a bridge be built, and that a steering group be
established to take the project forward.
The report contained no mention of the points which the respondents had
made in their letter of
 I was informed by counsel for the petitioners, in their submissions, that the Resources Committee accepted the recommendations in the report. A steering group (the Bridge Project Team) was established, headed by the petitioners' Mr Craigie. A budget of £15.559m was allocated to the project [7/6].
"I feel the [respondents'] Board would be better informed if they had the opportunity to discuss how each of the various parameters impacts on the viability of the bridge. For example, reducing the span to 125m and the air draft to 30m could reduce costs by up to £3m. A further reduction in span would further reduce costs. ... I believe a presentation [by the petitioners] to the Board followed by an open discussion would resolve this. We need to do this prior to 11 November [when the respondents' board was next due to meet], bearing in mind that time is very much against us if we are to secure EU funding" [7/45].
In relation to the last sentence, is appears that Shetland had ceased to be designated as an Objective 1 area for the purposes of grant aid under the European Regional Development Fund at the end of 1999, but that a transitional fund had been established on which the petitioners could draw [6/1, para 10.2.1]. In order to secure EU funding, the project had to be completed by the end of 2006 [7/6].
mentioned to you that the Board plans to discuss the matter of the bridge
parameters and review this I believe it will be, if anything, to increase the
parameters not to reduce them. We have
already had vessels with an air draft of 37.5 metres using the north entrance
and as one trawler skipper said, 'It's narrow enough already'. The
 The respondents then commissioned a study
from Arch Henderson on the impact of the proposed
 The report began by giving an overview of
the harbour. It noted that plans were
currently being made to accommodate predicted growth in the pelagic fish
processing industry and the offshore decommissioning industry. The related developments were planned for the
"The remainder of this report by Arch Henderson & Partners provides relevant cost development information and navigational data that will need to be considered and addressed by parties involved in the planning, design, funding and construction of the proposed Bressay Bridge in order that a minimal impact on future port development and harbour operations is achieved."
 In relation to the layout of the North
Harbour, the report noted that there was a dredged navigation channel (-9m CD),
dating from 1998, through the northern part of the north entrance, at Turra
Taing, with a dredged turning basin to its south, beside the deep water quay
development at Greenhead. In the
southern part of the north entrance there was the dredged navigation channel previously
mentioned (-6m CD), dating from 1990, which passed between Point of Scotland and
Heogan into the North Harbour, where it then bent in the direction of the
Shetland Catch factory at Gremista Pier.
The Shetland Catch factory had undergone recent development, including
the construction of a deep water quay and the largest pelagic fish cold store
 The report noted that respondents had in 2002 commissioned a report into suitable sites for further expansion by Shetland Catch. The conclusion had been that Gremista Quay was the only suitable area. The current proposal was for a large reclamation area (i.e. an area currently under water, which would be in-filled and reclaimed) and an additional 390m of berthing with a draft depth of -9m CD, suitable for the new generation of pelagic trawlers, refrigerated vessels and general shipping. That proposal was illustrated on a drawing, prepared by Arch Henderson, appended to the report. The drawing shows a wider and deeper navigation channel (-9m CD) at Point of Scotland. As illustrated, the channel would lie in a different orientation from the existing channel, lying broadly north/south, rather than north-west/south-east. It would lead into a turning basin (-9m CD) serving the new deep water quay and the Shetland Catch development at Gremista. In relation to the drawing, the report stated:
"The proposed future navigation channel requirements shown ... have been established based on this anticipated development [i.e. the current proposal for the development of the Gremista Quay area] together with other future port design criteria and available vessel data. The following section of this report discusses further the proposed future layout requirements of the navigation channel, other design parameters and how these must be assessed and developed into any future bridge proposals."
 In relation to the future design of the
 In relation to vessel data, information available in December 2002 suggested that the most critical data related to proposed new build pelagic trawlers, with a draft of over 8m, and the new passenger ferry Norrona, with an air draft of 42.8m. I was informed in counsel's submissions that the Norrona was a regular visitor to Lerwick, but could at present enter and leave the harbour only by the south entrance, as her draught was too great for the north entrance, and she was too long from bow to stern to make the turn to the south of Point of Scotland. In relation to navigational aspects, the existing navigation channel through Point of Scotland was recognised by some vessel operators as a restricted channel. The dredging of the outer access channel at Turra Taing had increased tidal flow, causing some vessels to drift to the west side of the Point of Scotland navigation channel. It was recognised that during any further development of the channel the dredged width would need to be increased and its orientation moved to a north/south axis, in order to cater for larger vessels and improve navigation and manoeuvrability.
"Based on predicted future vessel size and draft then the navigation channel width will need to be increased to 100m with the overall dredged channel 120m wide and -9m CD depth. The anticipated distance between bridge pier foundation supports corresponds to a minimum 160m but this dimension can only be finalised and agreed once site investigation information confirms final side slope stability characteristics of dredged channel. From the vessel data table above and after consideration of the Significant Wave Height and tidal surge likely then the required air draft under any part of the bridge structure needs to be a minimum clearance of 50m above Mean High Water Springs of +2.2m CD" [para 5.0].
In relation to the need for the dredged channel to be wider than the navigational channel, the report explained:
"The maximum channel width is a function of largest ship beam and length; maximum drift angle to current and wind; and an allowance for yawing due to wind effects."
 The suggested arrangement was illustrated by a drawing appended to the report (Appendix D). The drawing shows a dredged channel 120m in width. To either side of the dredged channel there is a side slope, sloping down from the undredged part of the seabed to the base of the dredged channel. No dimension is stated on the drawing for the side slope: as the passage quoted above explained, that dimension would depend on the stability characteristics of the slope, which could only be determined by site investigation. To the side of each side slope the drawing shows a berm, between the top of the slope and the edge of the bridge structure: in other words, an area of the seabed which has been left clear in order to reduce the pressure exerted by the bridge on the slope, so as to prevent the slope from collapsing (the idea is illustrated by the original meaning of "berm", to denote the space left by castle architects between the moat and the base of the castle wall). The berm is described on the drawing as a "minimum 10m berm": a minimum, presumably, because the appropriate dimension would have to be determined after site investigation. The drawing has a scale, and it is possible to measure the distance between the inner edges of the foundations of the bridge piers, i.e. the clear width. That measurement is 160m: 120m for the dredged channel, plus the minimum 10m for each berm, plus an allowance of 10m for each side slope. As the passage quoted made clear, however, that measurement was a minimum, which assumed that the site investigation would permit the minimum berm, and that the slope characteristics would be such that each side slope would be 10m. In that regard, the report noted that previous dredging at Point of Scotland had involved drilling and blasting, which could open up fractures and faults, with localised weakening of the strength of the rock. The report also observed that the difficulty of blasting adjacent to any bridge foundation, and the much higher cost of alternative dredging techniques, were matters to consider over the lifetime of any bridge structure.
"2.0 The proposed bridge crossing at Point of Scattland
is at a location of proposed future development of the
3.0 Dredging operations to create the above future navigational requirements could create significant conflict with any in-situ bridge structure and it will therefore be a requirement to consider dredging of the effected area of navigation channel as part of any civils contract for constructing the proposed bridge structure. The anticipated distance between bridge pier foundation supports corresponds to minimum 160m but this dimension can only be finalised and agreed once future site investigation information confirms side slope stability characteristics of dredge channel."
 The respondents provided the petitioners with a copy of the
report. The petitioners in turn sought a
response from Halcrow. Halcrow's
response [7/47] did not consider the question of the span of the bridge, but
was concerned almost entirely with the question of the vertical clearance. In that regard, Halcrow said that a clearance
of 50m would add about £5m to construction costs. They suggested that taller vessels currently
using the port, such as the Norrona
and Royal Navy destroyers, could instead be restricted to the south
entrance. Mr Craigie forwarded
Halcrow's response to the petitioners on
"I fully recognise that the Port Authority has not adopted a position regarding the report and the contents of the report represent the views and the opinions of your Consultants at this stage" [7/47].
 During 2003 the respondents obtained estimates from Arch Henderson for the dredging works which had been proposed in their report [6/3]. It is a matter of agreement between the parties that during 2003 the only dredging proposals which the respondents were considering carrying out as their next dredging campaign were those contained in that report, and that this was made known to the petitioners [17A].
 In order to proceed with the bridge proposal, the petitioners required a variety of statutory permission and orders. Under planning legislation they were required not only to apply for planning permission but also (as they were both the planning authority and the proposed developer) to publish a notice of intention to develop, and, in the event of representations being made, to notify the Scottish Ministers, in accordance with regulation 4 of the Town and Country Planning (Development by Planning Authorities) (Scotland) Regulations 1981 (SI 1981 No 829) as amended. Under roads legislation they required to promote a roads scheme. Other consents and orders were also required. During 2003 the petitioners decided to proceed with the planning application in advance of the roads scheme [7/7].
"In terms of the design there are a number of options available to adjust pier positions etc but in order to avoid unnecessary costs and abortive work, detailed discussions at a technical level will first be held to establish which options can be developed further."
 Mr Spall went on in the letter to discuss the notice of intention to develop ("NID") which the petitioners had to give in relation to the application for planning permission to construct the bridge and the associated road works, as explained above. In that regard, Mr Spall wrote:
"As you are aware, there is pressure to process the Notice of Intention to Develop in order to meet the project deadline. Clearly, there was insufficient time to complete these detailed discussions before the NID advert had to be placed in the paper on Wednesday 17 December. However, the NID is structured in such a way that the final detail surrounding the outstanding issues can be incorporated in the final design. This approach is in keeping with the discussion we had last week when I indicated that the Council would have to go forward with a proposal that is deliverable within the budgetary constraints and then take on board, as far as possible, amendments to deal with concerns or objections expressed.
I am keen to ensure that open and frank dialogue continues on the issue of the bridge, therefore this letter is sent to advise you of our intentions while giving reassurance that your very real concerns will be fully addressed as the formal consultation proceeds" [7/7].
 Although the letter stated that "we have advertised the NID",
the notice was not in fact issued and advertised until
 In considering the application for planning permission, it is necessary to bear in mind that (as was common ground between the parties) the bridge structure above the Sound of Bressay, including the piers supporting the central span of the bridge, falls outside the scope of planning legislation (Argyll and Bute District Council v Secretary of State for Scotland 1976 SC 248). At the same time, as counsel for the petitioners explained, the design of the bridge structure as a whole depends on the location of the central piers: for engineering reasons (including regulations governing the gradients of roads and bridges, and the curvature of roads), a change in the location of the central piers (other than a minor adjustment) would affect the remainder of the bridge structure and the alignment of the roads connecting the bridge to the main roads network. The planning application (and the subsequent compulsory purchase notice) depended on a view being taken as to where the central piers were to be located, even though the piers did not themselves fall within the scope of the planning application (or of the compulsory purchase notice).
 The drawings and plans which accompanied the planning
application and the notice were prepared by Halcrow, and were variously
labelled "Preliminary", "Issued for Information" and "Issued for Discussion". They showed the location and spacing of the
piers. One plan (TB-BRES-100 Rev F),
 The bridge shown on the first Halcrow drawing (TB-BRES-100 Rev F) thus departed in two important respects from the recommendations made by Arch Henderson. First, the central span was considerably narrower than the 160m minimum clear width which Arch Henderson had indicated would be necessary. Secondly, the vertical clearance was 40m, rather than the 50m minimum recommended by Arch Henderson. The second drawing (TB/BRES/SK 101 Rev A) was similarly incompatible with the information as to the clear width requirement provided by the respondents and their consultants.
"The bridge ... will have a minimum air draft of 40m above Mean High Water Springs (MHWS) under the central span, which will be 160m wide."
A footnote added:
"The width of the main span is under review in consultation with Lerwick Port Authority".
A later passage (at para 2.3.2) stated:
"The proposed design is illustrated in Figure 2.2 ... The central span will be 160m wide".
A footnote added:
"The final details of the bridge are under development in consultation with the Port Authority. The central span may be wider in the final scheme."
Figure 2.2 showed a central span of 160m as measured between pier centres. The clear width was significantly less, and depended on the width of the pier structures, which were annotated "Provision for ship impact to be confirmed". The dimension between each edge of the dredged channel and the nearest pier centre was shown as 20m. In relation to the rock islands, the environmental statement stated:
"The cofferdams [i.e. sheet piled structures constructed around the intended working area, to keep the sea out] for the main piers will be incorporated in the permanent works to act as ship protection [p IV]" [ p 10].
 As Mr Spall had requested in his letter of
"Further to the meeting in our office this afternoon between John Manson and Andy Sandison (Arch Henderson) and Kenn Allan (SIC) we can confirm that all parties are in agreement as to the location of the existing dredged channel. This is shown on the enclosed AutoCad drawing.
The location has been agreed, with the grid shown matching that shown on the Halcrow drawing of the bridge we received yesterday. Both surveys are in the same format and can be directly overlayed.
We have also shown the line of the proposed new dredged channel which Lerwick Port Authority wish to carry out.
Therefore this drawing of the channel will supersede all previous lines shown on Arch Henderson drawings and Halcrow drawings.
Please confirm receipt of this drawing, and the action to incorporate it on all existing and future bridge drawings."
 The attached drawing showed the location of the existing dredged channel. It also showed what was described as a "120m wide proposed channel", bounded on either side by lines labelled "edge of proposed dredged channel". Beyond each of the lines, there was another line labelled "top of sideslopes to proposed dredged channel". A docquet on the drawing stated:
"The above data relating to the
existing channel position has been agreed as correct at a meeting between John
Manson (Arch Henderson) representing Lerwick Port Authority, and Kenn Allan
representing Shetland Islands Council on
Proposed new 120m wide channel
(position of top of slopes (10m from main channel edge) running from SOP1 to
SOP3 [positions on the drawing] added
All existing and future
 The petitioners did not respond to the e-mail or acknowledge receipt of the drawing [6/19, para 6.6.4]. It is a matter of agreement between the parties that the e-mail was copied to Ms Laurenson, the Deputy Chief Executive of the respondents, that she printed a hard copy of it the same day, and that she cannot recollect whether the drawing was attached. It is also a matter of agreement that she would not in any event have been able to open the attachment .
"4. The objectors and their engineering advisers, in so far as they can determine the position from the Planning Application and supporting drawings or plans, believe the proposed development is likely to obstruct or impede the performance of their functions as Harbour Authority in terms of the Lerwick Harbour Acts and Orders 1877 to 2003 and various other general Acts and/or to interfere with the reasonable requirements of navigation over the waters, namely Lerwick Harbour. However, due to lack of salient design and construction information the objectors and engineering advisers are not able to advise fully on these aspects.
Matters of concern include the absence in the Application and supporting drawings or plans of precise details of the location and dimensions of the bridge, including supporting pillars, in relation to the navigation channel. No design data and maintenance information in respect of the proposed bridge is given. In addition, the width of its central span, as proposed, would be insufficient to permit safe maintenance and future development of the navigation channel. No details are given of the Hydrological study and Hydrodynamic modelling study referred to in the Environmental Impact Assessment and the effect of the proposed development on the harbour and vessels using same during both the construction and post construction periods.
In respect of dredging it may not be possible to dredge at all post-construction or if dredging is possible the costs are likely to increase substantially. In any event no information is provided as to how pier foundations are to be constructed or the protection of same from future dredging of the channel".
Concern was also expressed that the rock islands would restrict the width of the channel and therefore increase the speed of the water flowing through it, rendering the channel less safe for navigation, and reducing the size of the vessels able to use it.
"A. (i) The indicated width of the bridge span over the navigational channel is insufficient and in particular insufficient to accommodate its future development. The minimum width needs to be 160 metres measured between the inner edges of foundations adjacent to said channel. This objection presupposes pre-dredging of the navigational channel by the applicant. If this is not intended to take place then the minimum 160 metre width referred to will almost certainly need to be increased in order to accommodate potential future development.
(ii) Information on drawings, which is both conflicting and inadequate, has been provided regarding cofferdams in their use as ship protection or part of the temporary causeways becoming permanent as man made rock islands. The position is, therefore, unacceptably uncertain and their impact cannot be assessed.
(iv) Insofar as the ES comments on the effect of the temporary causeways/islands, the studies are absent and no detailed information on this topic is given. No consideration has been given to the effects of the bridge on navigation of vessels except in relation to air draft. This gives rise to serious actual and potential concerns regarding likely difficulties, details of which are contained in the annexed initial comments and concerns, with diagram annexed, by Captain Archer T L Kemp, Harbourmaster of Lerwick Harbour, which comments and concerns form part of these objections.
(vi) There is a failure to appreciate that not only is the navigational channel used by vessels entering from the north but also it is in regular use by internal harbour traffic including, for example, vessels entering from the south, reefer vessels loading cargo at the Greenhead base and Gremista, inshore and pelagic fishermen, pleasure craft, pilot cutters, Lerwick Port Authority work boats and the like.
The suggestion that vessels can go round Bressay [i.e. so as to enter the harbour by the south entrance] if the channel is blocked or restricted is unreasonable and unsatisfactory and does not conduce to the efficient running of Lerwick Harbour ...
(vii) If a large vessel such as the Norrona, which recently grounded in Torshavn harbour [in the Faroes], were to ground in the North Ness channel, the objectors would be faced with the prospect of harbour traffic, e.g. the NorthLink ferries which berth at Holmsgarth requiring to use the north channel until the North Ness channel was cleared. No assessment has been made of the impact of the bridge in such an event."
Captain Kemp's observations, which were incorporated into the objections, emphasised the difficulty of navigating the existing channel, as a result particularly of tidal flows, and expressed concern that the further restriction of the channel would exacerbate that problem.
"MC [Mr Craigie of the petitioners] said that from previous discussion and correspondence with LPA [the respondents] it was known ... that there were elements of the draft proposals which they felt were unacceptable.
AW [Mr Wishart of the respondents] said that the potential for future dredging had to be carefully protected. The draft requirements of vessels likely to be using the port were constantly being increased. The design of the bridge should not therefore inhibit dredging in the vicinity of the middle piers ...
AW referred to correspondence from 1998 and 1999 setting out LPA's position on bridge dimensions. Two letters from LPA were demonstrated which clearly indicated requirements including a 160 metre clear width requirement. AW said that another option was to increase the centre span to, for example, 180 metres. This would move the piers clear of the navigable channel. MC said that this was still a possibility but that it would involve extra cost. The report to Council will present such options, with attendant costs."
Mr Wishart was asked to explain his suggestion of a central span of 180m:
"AW explained that this was based on an official navigable channel width of 100 metres. 10 metres on each side of this had to be added as an allowance for 'navigational buoy excursion' plus another 10 metres each side to account for the construction of a stable dredged slope and a further 10 metres berm (ledge at edge of slope) to the inner side of pier base. 20 metres is assumed as the diameter of the central pier foundation structures. He felt that 180 metres between centres would be required to ensure that the pier bases were far enough from the edge of the dredged channel. This would allay LPA concerns regarding future dredging."
As counsel for the petitioners acknowledged in argument, Mr Wishart's suggestion of a span of 180m, measured between pier centres, was effectively the same as the earlier request for 160m clear width, if the diameter of the pier structures was assumed to be 20m. The only new matter was Mr Wishart's explanation that the 120m channel included an allowance of 20m for navigational buoy excursion. In relation to that matter, it was explained in submissions during the first hearing that the navigation buoys are anchored by chains, which are more or less taut depending on the state of the tide. To the extent that the chain is slack, the buoy can drift.
 Mr Sandison of Arch Henderson said at the meeting that the respondents now intended to dredge the channel to a depth of -10m CD. He also expressed concern that the proposed design of the pier foundations was inadequate and did not comply with the relevant guidelines regarding ship collision. Mr Wishart said that this concern also would be abated if the main span, measured between pier centres, was extended to 180m. Mr Craigie responded "that this option would be costed and presented to the Council along with the others".
"The current pelagic fleet can draw as much as 8.5 metres. The Icelandic vessels which may use the port in the future draw up to 10 metres. The freedom to dredge in this area in future was therefore a major concern."
It was noted that the bridge foundation would need to be reconsidered if the dredge depth were increased to -10m CD. Concern was also expressed about the effect of the bridge construction on the current flowing through the channel, and thus on navigation.
"He explained in some detail the highly competitive nature of ports and their businesses, particularly Oil and Fishing. Any impediment or restriction to free and safe vessel movement would be picked on by a competitor as a good reason for existing and potential customers to avoid Lerwick. MC acknowledged this ...
AW said that LPA had a duty to protect the interest of the harbour and could therefore not compromise on navigational issues. He felt that SIC have the ability to resolve the issues by increasing the funding for the project."
"As part of this procurement, we are currently carrying out consultation with businesses in the area that may be affected by the works together with submission of all marine consent application to various statutory bodies.
We attach general drawing for the proposed works for your records ... while the works do not form part of local authority planning legislation, we would welcome any comments you may have regarding the proposed works."
A general drawing of the proposed works was enclosed. In the area of the proposed bridge, the drawing indicated that the channel was to be dredged to -10m CD. The width of the dredged channel was not stated, but could be measured from the drawing as 120m.
"7. All agreed it was unlikely LPA would withdraw its objections to the NID ...
8. SIC project team's design is very much a 'work in progress'. They are looking at various engineering solutions, including a totally different method of construction, to try and meet objectors concerns but remain within SIC budget.
9. Discussed how long they were going to try and engineer issues away - not much time left with ERDF application due in September.
12. SIC project team say that the NID being passed to the Scottish Executive is only relevant in the context of the onshore parts of the project. An application under the Roads Act and the Works Licence Application will deal with the navigation issues.
15. SIC project team still appear not to want to bend at all, keep mentioning reducing the width of the dredged channel - LPA keep saying this is not negotiable ...
16. LPA repeated its fundamental requirement for 160m clear span width between pier bases, unchanged from 1998. This may mean 180m between pier centres.
19. LPA expressed lack of confidence in the Hydrodynamic modelling done by Halcrow. Requested an independent model.
20. Michael Craigie reluctant to commit to this, however team did say that enhanced modelling would be necessary as the final design progressed, perhaps there would even be a different design of bridge to be modelled."
"5.6 The Team will consider the potential costs and benefits of increasing the span of the bridge to at least 180m. The LPA and other objectors raised concerns about the proposed span of 160m primarily because of navigational issues.
5.7 As an alternative to increasing the span, the Team will explore, in consultation with the LPA, the potential to reduce the width of the proposed dredged channel from 120m to the minimum 100m through the use of navigational aids.
5.12 If the Council is to be
in a position to secure ERDF funding for the construction of the
· Completion of further options appraisal;
· Development of the detailed design of the final option;
· Development of the final cost model. This must be concluded before the Council makes a final commitment to build the bridge;
6.2 These costs [i.e. the estimated cost of the bridge] can only be identified when all the objections have been addressed and the details of the project finalised. Indicative additional costs for addressing some specific objections such as moving the bridge location to the north or increasing the span of the current option, are included in Appendix 1 for information."
The appendix referred to [7/11] was a report by Halcrow and other consultants instructed by the petitioners, dated May 2004. It stated:
"11.6.1 The Team will further explore options to increase the main
span of the bridge to at least 180m in order to address the LPA's concerns
regarding future dredging in the
11.6.2 As an alternative to increasing the span, the Team will explore, in consultation with the LPA, the potential to reduce the width of the proposed dredged channel from 120m to the minimum 100m".
 The notice of intention to develop, with
the planning application and the environmental statement, was submitted by the
petitioners to the Scottish Ministers on
"Our recent telephone conversations when you advised that you would like to arrange a brief meeting to discuss the following main issues refers:
2. LPA dredging operations.
3. New channel alignment.
I am afraid that the date and time you have suggested is not suitable for us owing to various personnel being on leave and other workload/commitments.
In order to assist you in the meantime, I detail below a brief response regarding each of the above issues that may assist you in the meantime.
2. Our dredging proposals have not fundamentally changed from the information prepared by Arch Henderson LLP and provided to you previously.
3. Our new channel alignment has not changed from the information prepared by Arch Henderson LLP and provided to you previously.
I hope that this information is of use to you in the meantime ..."
"hereby authorised to construct, along the route described in Schedule 1 hereto, as part of a public road, a bridge ... in accordance with Schedule 2 to the Scheme ..."
1 specifies the route of the public road, as shown in Plan 1. Plan 1, dated
"Specification of bridge over Bressay Sound showing the position, clearance for passage of vessels and dimensions of the proposed bridge."
Under the heading, "Position", it states that the position of the proposed bridge is shown on Plan 1. Schedule 2 continues:
"Clearances for the passage of vessels
Ten piers shall support the final bridge construction. The central span of the proposed bridge between piers five and six, measures one hundred and sixty metres or thereby and crosses over the existing 90 metre or thereby channel. The said 90 metre or thereby channel is shown edged in green on Plan 1....
The central span of the proposed bridge accommodates a height clearance of 40 metres above Mean High Water Springs over a 120 metre or thereby width.
The 120 metre or thereby width and the 40 metre clearance are shown in ... Plan 2 ..."
It is to be noted that, although the proposed 120 metre dredged channel is shown on Plan 1, the passage quoted from Schedule 2 does not refer to that channel, but to "a 120 metre or thereby width" shown on Plan 2. Schedule 2 also states that "the dimensions of the proposed bridge are shown on the said Plan 2".
 Plan 2, dated
"Proposed dredged channel
Plan 1 ... shows the edges of a 120 metre wide channel ... that Lerwick Port Authority has proposed to dredge in the future. It is shown in this Scheme to indicate that should the channel be dredged to 120 metres the proposed bridge would be able to accommodate that width of channel as well as the existing 90 metre channel."
For the reasons I have explained, a bridge constructed as shown in Plan 2, and located as shown in Plan 1, would not allow a 40m vertical clearance across the width of the channel.
 When this matter was raised during the present hearing, counsel for the petitioners said that it was accepted that Plan 2 was inaccurate. It had not been intended to show the exact relationship between the navigational "envelope" (i.e. the 40m clearance across a 120m width) and the centre span, but rather to illustrate the principle that a suitable navigational envelope could be provided. A further drawing [6/32], prepared for the purposes of the hearing, was produced to demonstrate how the envelope would be provided. This drawing shows the central piers located as in Plan 1, with the central span positioned asymmetrically relative to the proposed 120m channel. Pier 6 (the eastern central pier) is shown as being taller than pier 5 (the western central pier), so as to move the 120m envelope closer to pier 6, bringing it into alignment with the 120m channel. Counsel explained that the difference in height between piers 5 and 6, and the consequent alignment of the road, were also shown on one of the drawings accompanying the planning application (Drawing No. TB-BRES-R-05) [10/3(i)]. The distance between the centres of the piers is 160m, with each pier having foundations surrounded by impact protection consisting of concrete and granular fill, with a diameter of 26m. The clear width between the piers is therefore 134m, which is 26m less than the minimum the respondents' officials had said would be required. The space between the edge of the 120m channel and the nearest rock island is shown as 3.25m on the east side, and 10.75m on the west side. The respondents' officials had requested a minimum of 20m on each side.
 In relation to this drawing, counsel said that the works licence application and the application under the Coast Protection Act 1949 ("the 1949 Act") defined the positions of the central piers in terms of latitude and longitude to an accuracy of 0.01 of a minute, which was equivalent to ± 4.7m. In response to counsel for the respondents' observation that a margin of 3.25m between the pier and the edge of the channel was incompatible with a tolerance of ± 4.7m - in other words, that the pier might in the event be located in the channel - and that the margin was less than the minimum stipulated in the relevant guidelines, counsel for the petitioners responded that these were not matters for the court. It was accepted that the piers would have to be located with a higher degree of accuracy than was envisaged in the works licence application or the application made under the 1949 Act. Whether the design was achievable was not a matter for the court.
4. ... Due to these
concerns, LPA has commissioned Eagle,
6. The indicated width of the bridge span over the navigational channel is insufficient and in particular insufficient to accommodate its future development. The width will need to be increased in order to accommodate potential future development and in particular the proposed alteration and widening of the existing navigational channel by LPA to a width of not less than 120 metres to meet the needs of increasingly large vessels.
In this regard we annex a drawing by LPA's engineering advisers Arch Henderson LLP. Lerwick, namely drawing number 202576-30 dated August 2004 which clearly demonstrates the conflict between Lerwick Port Authority's proposed new dredged channel and Shetland Islands Council's proposed position of piers 5 and 6 which support the central span of the proposed bridge.
14. The air draft of the
bridge namely 40 metres is insufficient to accommodate the air draft of vessels
... with air drafts in excess of 40m presently using
The Arch Henderson drawing referred to [7/13] was prepared on the basis that the main span would be centred over the proposed 120m channel, as shown in Plan 2 of the road scheme. Even so, the drawing shows piers 5 and 6 as encroaching into the areas of the side slopes; and there is no space for a berm on either side.
 During August 2004 the parties received a
report on the economic impact of a bridge to Bressay which they had jointly
commissioned from DTZ Pieda Consulting [7/39].
It concluded that, in a best case scenario, the bridge would generate an
additional two jobs. It noted that the
average tonnage of vessels at
"[T]he information available on vessel size supports an overall trend of vessel growth with some evidence that oil related and ro-ro vessels are undergoing more significant expansion."
The report also noted:
"Both [the petitioners and the respondents] have already clearly stressed that further examination of technical areas such as hydro-dynamic modelling is required. Until further examinations are completed potential impacts on navigational issues and maritime safety cannot be assessed in a robust manner" [para 5.9].
In relation to the oil decommissioning market, the report concluded:
"[I]t would not be unreasonable to assume that Lerwick Harbour may capture up to a fifth of the overall Scottish share of the decommissioning market, around £860m" [para 6].
The annual income in Lerwick which could be derived from decommissioning was estimated at £22.7m, equivalent to 265 jobs.
"... that the works for which a licence has been applied for if constructed in accordance with the Application and its accompanying plans, sections and particulars are likely to obstruct or impede the performance of the Authority's functions under the Lerwick Harbour Acts and Orders and are likely to interfere with the reasonable requirements of navigation ...".
Along with the decision, the respondents provided the petitioners with papers which included the Summary and Conclusions sections of the draft of the report which they had commissioned from ELP [7/15]. In the draft report, issued on 20 August 2004, ELP had calculated the width requirements of the dredged channel using International Navigation Association (INA, formerly PIANC) methods, taking as design vessels the Maersk Assister (a vessel of a class which already used the channel), and the Norrona. These required (according to the INA method of calculation) a dredged channel width of 105.6m and 150.5m respectively. If these widths were to be reduced, then a series of simulations should be carried out. The draft report also stated:
"7.2.1 The obvious mitigation for all concerns regarding the bridge construction is for vessels to use the South access channel, instead of transiting the proposed bridge site. This is too simplistic an answer and quite apart from the additional steaming time that may be involved (up to 16 nautical miles) the reason that the port can maintain a high level of accessibility in extreme environmental conditions is that it will be possible (with few exceptions) to enter the port from either the north or south dependent on the prevailing wind direction. Without this dual access arrangement downtime at the port may significantly increase thus making it less attractive to potential customers."
 On about 27 August 2004 the
petitioners applied to the Scottish Ministers for consent under section 34 of
the 1949 Act, which prohibits the carrying out of operations detrimental to
navigation without their consent. The
application described the works involved as the construction of a bridge "with
a main span of 160m providing an air draft of 40m minimum over the proposed 120m
wide dredged channel" [10/6]. The accompanying drawings were not produced
at the present hearing. The application
was subsequently withdrawn, as the co-ordinates given in the application were
incorrect. A fresh application was
"The project is currently progressing through the various consents processes and detailed design will commence soon" [7/16].
 ELP's report in its final form ("the first
ELP report") was issued on
"The required channel width at the proposed bridge site should be in accordance with INA recommendations or tested with a series of fast time manoeuvring simulations, to be appropriate to the expected traffic population of the port" [para 6.2.7].
In view of that advice, the respondents decided to instruct ELP to carry out manoeuvring simulations based on their proposed 120m navigation channel, and provide a second report. The petitioners were provided with a copy of the first ELP report [7/19].
"the port authority to specify what modifications would be required to the proposed bridge in order to satisfy your requirements and remove your objections. The purpose of seeking the information is so that the members can have your requirements properly evaluated and costed. A meeting can then be held at the most senior level with all the information on the table.
It may be that you feel that you have already stated what your requirements are but it would greatly assist if you could set them out in response to this request so that there is no dubiety about what you would wish the Council to do" [10/12].
"[Y]ou will be aware that the size of vessels using the north harbour has increased substantially and this has therefore necessitated a review of our position. Expert advisors have already provided guidance in this respect based on the International Navigation Association method for calculating channel width requirements. We wish to have these recommendations tested with a series of manoeuvring simulations for ships now using the north harbour and also for ships whose owners have indicated that they would prefer to use the north channel if it were dredged sufficiently. Once we have received and included our expert's report in an overall assessment of requirements, I will contact you again, at which time I hope we will be able to jointly move forward."
 By letter dated
"[W]e have said in writing from 1998 that we require at least 160m clearance between the bases of the main stanchions, that we would require the channel dredged to 8 metres depth and that the air draft would certainly require to be not less than 40 metres. ...
During the past six years we have found that the proposed dredged depth of 8 metres is not adequate for many of today's ships and that the proposed air draft is insufficient for many of the vessels that now use the harbour. It is also very likely that the centre span width will have to be increased. We have already made available to you a study by Eagle Lyon Pope that should, as advised to Michael Craigie, give you a good 'steer' on centre span width requirements.
... I have also made it clear on different occasions that a statement of our requirements will not necessarily satisfy the objectors to the bridge proposal who are mostly significant businesses and employers in the port and whose views, in respect of the Council's Work Licence Application, we are statutorily obliged to consider.
... I am confident that we will win some of the Frigg oilfield decommissioning work as well as work arising from the renewed interest in West of Shetland offshore oil exploitation. Many of the present generation of oil related vessels would not be able to pass through the north channel if the present bridge proposals were to go ahead. The proposed bridge would effectively cut the harbour in two. Even the latest local trawlers require 9 metres of water and this gives a strong indication that still more dredging will be necessary in the long term. We would be failing in our duty as port operators if we did not guard against threats to the port's ability to continue to allow freedom of navigation for all types of shipping, particularly as ships continue to increase in size. We must not be inhibited in opportunities to fully utilise existing infrastructure, nor prevented from developing the port so as to attract future generations of shipping."
"We have had further studies undertaken of our proposed dredging of the north harbour. We have found that the whole length of the channel from the north entrance at Turra Taing to the south end at Point of Scotland will need to be re-orientated. Our studies are not yet complete but we are examining firstly, the effects of moving the north end of the channel to the east with the south end being moved to the west and secondly, the widening of the channel in places particularly at the south end on the west side to at least 140 metres... Clearly, this means that changes will be required to the width and position of the bridge's centre span.
Turning to air draft, you are aware that
there are specific Objections to the granting of a Works Licence in this
regard. Two Objections specified a
minimum air draft requirement of 50 metres.
I pointed out in my letter of
 In the light of the second ELP report, Arch Henderson had made
revisals to the proposed navigation channel, as described in the respondents'
 A meeting between representatives of the parties was held on
"[The respondents] highlighted the
difficulties that the present plans present to the LPA because of the location
of the central support legs and the proposed dredged channel for
There was some debate on the positioning of the legs and how that could be altered to accommodate some of the concerns from LPA ...[The petitioners'] Chief Executive Morgan Goodlad suggested that there may be opportunities to modify the plans more in line with the requirements to suit the LPA. ... There was some disagreement at this point on the position of a bridge leg. ... Allan Wishart [of the respondents] suggested that there may be an option of a tunnel ... Morgan Goodlad responded that tunnelling was not discounted but estimates that the SIC Project Team have on tunnelling suggest that it would be potentially a lot more expensive and technically more difficult. ... Morgan Goodlad said the SIC should have an open mind at addressing costs of any changes that may be required to overcome the problems foreseen by LPA. ...
... [It] was agreed that the SIC would look at the repositioning of the pillar [i.e. pier 5] and seek costings for the changes required to the design of the bridge."
I was informed by counsel
for the petitioners that the accuracy of the note was not disputed. At the meeting, the respondents had shown the
petitioners' representatives a drawing of Arch Henderson's revised dredging
proposal [7/35], showing that the west pier of the proposed bridge (pier 5)
would stand in the dredged channel. The
petitioners' Chief Executive requested the co-ordinates of the position which
would be required to locate the pier outside the channel [7/28; 10/23].
The respondents sent the co-ordinates on
 ELP's report on ship manoeuvring simulations in respect of Arch
Henderson's revised proposal ("the third ELP report") was submitted in draft on
"[O]ver the past few months it has emerged clearly that the orientation of the dredging for the north channel has to be altered with the south end moving west and the north end moving east to create as straight a line as possible for ships transiting the channel. This means that the proposed bridge's west side main pier will be located in the dredged channel ... However we are now in the final stages of deciding the precise position of the dredging line on the west side. To assist in making that final decision we will be taking further core samples early next year and when they have been analysed that information will be made available to the prospective dredging contractors. Once that process has been completed we will advise you of the channel's position and its other relevant details."
 At a meeting of the Bressay Bridge Project Liaison Group on 29 January 2005, at which the respondents were not represented, the petitioners' Mr Craigie stated that the bridge design had been "drawn up around a formal agreement between the Lerwick Port Authority and the council that identified the position of the existing and proposed channel", and had been "drawn up to the agreed minimum requirements". There was in fact no formal agreement, and the petitioners had decided to disregard the respondents' minimum requirements in respect of the clear width, side slopes and berms.
 At a meeting between the parties on
 On the same date the respondents enquired about the
petitioners' assessment of the co-ordinates provided on
 The final version of the third ELP report was submitted on
 In relation to this matter, counsel for the petitioners explained the petitioners' understanding to be that it had been necessary for them to apply for a works licence. The effect of the respondents' subsequent objection to the roads scheme, however, had been to necessitate private legislation (as explained below). Such legislation, if enacted, would have the effect of excusing the petitioners from the necessity of obtaining a works licence, by virtue of section 13(1) of the 1974 Order. It was also envisaged by the petitioners that the private legislation would deal with the issue of consent under the 1949 Act, and with the authorisation of the proposed compulsory purchase.
 On 28 June 2005 this court reduced the Scottish Ministers' decision not to require the petitioners to make an application to them for planning permission, the Scottish Ministers having conceded that their decision had been invalid [6/20].
 The respondents placed a contract for dredging operations in
accordance with the advice received from ELP, at a price of £6.5m, with
demurrage running at £2,250 per hour.
Operations were due to begin on
 I was informed by counsel for the petitioners that a draft of a Private Bill had been prepared, dealing with the issues arising in connection with the 1949 Act, the 1984 Act and the proposed compulsory purchase.
 I was informed by counsel for the respondents that oil decommissioning work was expected to begin in 2008. The harbour had to be dredged in time, if decommissioning contracts were to be awarded to companies based in the harbour. The procurement process for dredging works was expected to last 6 to 9 months. The dredging itself could take 12 months.
The legislative framework
 A number of statutory regimes feature in the present case. The most important are (1) the provisions relating to the powers and responsibilities of the respondents and (2) the relevant provisions of the roads legislation.
1. The respondents' powers and responsibilities
 The respondents are the statutory successors of the Trustees of
the Port and
"Subject to the provisions of this Act, the undertaking of the trustees shall consist of the improving, deepening and cleansing of the harbour or of such portions thereof as the trustees may in their discretion think fit ..."
The subject of dredging was
dealt with more specifically in the Harbours, Piers and Ferries (
"The following provisions shall have effect as regards any marine work to which this Part of this Act applies:-
(b) The [harbour] authority may dredge, scour, deepen, and maintain the said work and the entrances and channels thereof. ..."
It appears from sections 15
and 16 of the Lerwick Harbour Order Confirmation Act 1952 that section 9(b) of
the 1937 Act is applicable to
"The Trustees may deepen, widen, dredge, scour, cut and improve the sea bed of the harbour and the seaward approaches thereto, and for such purpose may blast any rock therein."
Section 10(1) conferred on the Trustees a power to grant "works licences":
"The Trustees may upon such terms and conditions as they think fit grant to any person a licence to construct, place, maintain, alter, renew or extend any works on, under or over tidal waters or tidal lands below the level of high water within the limits of the harbour notwithstanding any interference with public rights of navigation or other public rights by such works as constructed, placed, mentioned, altered, renewed or extended."
The procedure to be followed by the Trustees when dealing with an application for such a licence is laid down by section 10(2) - (4). In particular, subsection (2) requires that the application must be advertised with a notice
"stating that any person who desires to object to the Trustees to the granting of the application should do so in writing stating the grounds of his objection ..."
Subsection (3) provides:
"In deciding whether or not to grant a licence or as to the terms and conditions to be included in the licence the Trustees shall take into consideration any objection ... and in granting a licence the Trustees may require modifications in the plans, sections and particulars submitted to them by the applicant."
Subsection (4) requires the Trustees, if they decide to grant a licence, to notify objectors. Section 12 deals with appeals against the grant or refusal of a works licence. Both applicants and objectors are given a right of appeal to the Scottish Ministers. Section 13(1) provides:
"No person other than the Trustees shall -
(a) construct, alter, renew or extend any works on, under or over tidal waters or tidal lands below the level of high water within the harbour limits unless he is licensed to do so by a works licence. ...
Provided that this subsection shall not apply to the construction, alteration, renewal or extension of any such works ... specifically authorised under any enactment."
"Provision may be made by a scheme under this subsection -
(a) made by a local roads authority and confirmed by the Secretary of State ...
for the construction, as part of a public road (other than a special road) of a bridge over ... any specified navigable waters."
The procedure to be followed in respect of the making of such a scheme is governed by Parts II and III of Schedule 1 to the Act, to which effect is given by section 75(4). In particular, paragraphs 9 and 10 of Schedule 1 require that notice of the proposed scheme should be advertised and also served on the relevant navigation authority, with a period allowed for the lodging of objections. In the event that an objection is received from the navigation authority, the Scottish Ministers are requested by paragraph 11 to cause a local inquiry to be held. That requirement is however subject to paragraph 19, which is concerned with schemes and orders which are subject to special parliamentary procedure. In relation to that procedure, section 76 is relevant. Under section 76(2), a scheme which provides for the construction of a bridge over navigable waters
"shall include such plans and specifications as may be necessary to indicate the position, clearances for the passage of vessels and dimensions of the proposed bridge".
Under section 76(4), if an
objection to a scheme is made by a navigation authority on the ground that the
bridge is likely to obstruct or impede the performance of their functions under
any enactment, or to interfere with the reasonable requirements of navigation,
then the scheme is subject to special parliamentary procedure, and paragraph 19
of Schedule 1 has effect so as to modify
in certain respects the application of the Statutory Orders (Special Procedure)
Act 1945. The consequence is that,
instead of the Scottish Ministers deciding whether to confirm the scheme following
a local inquiry, it is instead necessary for private legislation to be promoted
under the Private Legislation Procedure (
3. Inter-relationship of the works licence application and the roads scheme
 It follows from section 13 of the 1974 Order that, prima facie, the petitioners require a works licence in order to construct the piers of the bridge within the Sound of Bressay. They were correct to apply for such a licence, and the respondents were correct to deal with that application. The petitioners having subsequently made a roads scheme, and the respondents having objected to the scheme as the relevant navigation authority, on the ground specified in section 76(4) of the 1984 Act, it follows that the scheme will be subject to private legislation procedure. If the scheme is authorised, then a works licence will no longer be required, by virtue of the proviso to section 13(1) of the 1974 Order. If the scheme is not authorised, then the appeal against the refusal of a works licence will (unless withdrawn) remain before the Scottish Ministers for determination. In practice, there might be thought to be little point in persisting with the appeal in such circumstances, but that would be a matter for the petitioners to consider.
The petitioners' case as pleaded
 Since it was agreed that the court should proceed on the basis of the pleadings as well as the submissions, it is relevant to note the basis on which the petitioners' case is pleaded:
"That, during the course of 2003, the respondents' represented to the petitioners that the depth of the proposed dredged channel would be -9m CD with a width of 120 metres which the petitioners then relied upon to design the proposed bridge ... By an email dated 9 January 2004 the respondents unequivocally advised the petitioners to confirm receipt of the drawing showing the location and line of the proposed dredged channel 'and the action to incorporate it on all existing and future bridge drawings' ... The petitioners relied upon these representations from the respondents, confirmed by and evidence in writing by the respondents by email dated 9 January 2004 as the basis for defining the pier positions in their applications for the necessary statutory consents for the road bridge, including the Notice of Intention to Develop in December 2003, the roads scheme ... and the Compulsory Purchase Order ... Reference is further made to a letter from Arch Henderson & Partners dated 13 April 2004 together with attached drawing ... Reference is also made to an email from Victor Sandison the respondents' administration manager, dated 17 May 2004 ... [Stat 7].
The respondents were ... well aware that their original dredging proposals ... upon which the petitioners had relied, informed the final design of the proposed road bridge in respect of which the petitioners are seeking now planning consent. ... [T]he respondents have consistently represented to the petitioners that the design of the bridge with a 160 metre span would be sufficient to accommodate the respondents' future dredging proposals ... [I]t was not and could not have been reasonable for the respondents to believe that the design of the bridge was not fixed or that the petitioners were seriously considering the possibility of increasing the distance between the central piers after the statutory consents process had commenced [Stat 8].
... At the time the petitioners commenced the
statutory consents process on
[T]he petitioners had a legitimate expectation that the respondents' dredging proposals would proceed on the basis of the original proposals ... For these reasons, the decision to revise their dredging proposals should be reduced ... Separatim, the petitioners had a legitimate expectation that the respondents would not implement their revised dredging proposals pending the outcome of the statutory consents process [Stat 21]."
The submissions for the petitioners
 On behalf of the petitioners, it was submitted that the petitioners had a substantive legitimate expectation that the dredging works carried out by the respondents would be 120m in width in the area affected by the bridge proposals. That expectation was derived from Mr Manson's e-mail of
 The Arch
 The matter had been taken further by the e-mail sent by Mr Manson
to the petitioners on
"All existing and future
Mr Manson must be taken to have had ostensible authority, if not actual authority, to represent to the petitioners the location and width of the proposed channel. That could be inferred from the pleadings, productions and submissions on which the parties invited the court to determine the matter.
 The drawing attached to Arch Henderson's letter of
 The petitioners were entitled to assume that those representations set out the respondents' final position as to their future dredging proposals. The bridge was a permanent structure. Its piers could not stand in a navigation channel. Any information provided by the respondents for the purpose of enabling the petitioners to design the bridge must implicitly be final. If they had wished to leave open the possibility of dredging a wider channel at some point in the future, they should have said so. The petitioners had felt able, in the light of those representations, to proceed with the statutory consents process, on the basis that their bridge design accommodated the proposed 120m channel.
 Counsel acknowledged that the petitioners' design did not provide the 160m clear width which the respondents had represented was necessary: the clear width provided was 134m. That however was not the representation which the petitioners had regarded as critical to the design of the bridge. The critical factor for the petitioners in designing the bridge was the representation as to the width of the proposed channel, ie 120m. The design was based on that representation, notwithstanding that the space between the central piers was less than the respondents had said they required. The engineering advice given to the petitioners by their consultants was that their design was adequate to accommodate the respondents' plans.
 In relation to the last point, counsel said that the petitioners had been advised that it was unnecessary to make any allowance for a berm or for a side slope. The petitioners (who were themselves the harbour authority for Sullom Voe) considered the presence of side slopes on the plans to be irrelevant to the question whether their proposed design could accommodate the proposed dredged channel. They had decided to make no allowance for side slopes. If, in the event, the channel (including side slopes) was wider than the clear width of 134m for which the petitioners' design allowed, the petitioners could construct the piers within the side slopes.
 Counsel acknowledged that the latter points were merely ex parte submissions. The court was being invited to resolve the matter on the documents, without hearing evidence. The petitioners were not saying in the present proceedings that their design would accommodate a 120m dredged channel. They were saying, rather, that any issues as to the ability of their design to accommodate the respondents' requirements should be dealt with in the statutory consents process. The court was not entitled to consider whether the petitioners' design was in fact compatible with the respondents' original proposals: Parliament had confided that question to a public inquiry.
 The location of the piers was thus based on the respondents' representations as to the width and orientation of the 120m channel, notwithstanding that the space between the piers was less than the respondents had said they required. The location of the piers was critical to the entire design of the bridge, since a change (other than a minor adjustment) in their location affected the alignment of the connecting roads, which could in turn affect the scope of the orders sought under powers of compulsory purchase.
 In the event, the bridge design was incompatible with the revised dredging proposals. The respondents should not now be allowed to frustrate a consents process which had been based on their representations. The petitioners had spent over £1m in total on the consents process. That expenditure would be wasted if the respondents proceeded with their revised proposals.
 In making binding representations as to their future dredging plans, the respondents were not acting ultra vires. The power to grant a works licence, under section 10 of the 1974 Order, demonstrated that the respondents had the power to permit operations which would interfere with the operation of the harbour and with public rights of navigation.
 In argument, senior counsel accepted that the planning
application made in December 2003 could not be said to have been made in
reliance on a clear representation as to the respondents' final position. Counsel submitted that the petitioners had
however relied on the e-mail of
 Invited to explain the nature of the expectation or entitlement (if any) which the petitioners claimed, counsel said that they possessed what could be described as a right to build the bridge as designed, subject to obtaining the necessary statutory consents. Alternatively, they possessed an entitlement as to how the respondents would exercise their power to carry out dredging.
 In support of these submissions, counsel referred to Attorney-General of Hong Kong v Ng Yuen Shiu  2 AC 629, R v Inland Revenue Commissioners ex parte MFK Underwriting Agents Ltd  1 WLR 420, R v Devon County Council ex parte Baker  1 All ER 73, R v Jockey Club ex parte RAM Racecourses Ltd  2 All ER 225, McPhee v North Lanarkshire Council 1998 SLT 1317, R v North and East Devon Health Authority ex parte Coughlan  QB 213, R v Secretary of State for Education and Employment ex parte Begbie  1 WLR 1115, Lafarge Redland Aggregates Ltd v Scottish Ministers 2000 SLT 1361, R (Bibi) v Newham LBC  EWCA Civ 607,  1 WLR 237, R (Zeqiri) v Secretary of State for the Home Department  UKHL 3,  Imm AR 296, R (Reprotech (Petsham) Ltd) v East Sussex County Council  UKHL 8,  1 WLR 348, Royal Borough of Windsor and Maidenhead v Dewar  EWHC 154, and Rowland v Environment Agency  EWCA Civ 1885,  Ch 1.
 In the course of the argument, junior counsel for the petitioners also made criticisms of the ELP reports, and of the respondents' decision to act on the basis of those reports. It was suggested that the ships, weather conditions and currents selected for the simulations were inappropriate, and that the south entrance to the harbour in any event provided an adequate means of access and egress. Counsel also sought to argue that the respondents' revised dredging proposals were less extensive than the dredging recommended in the final ELP report, and therefore failed to implement that report. In that regard, a minute of amendment  was allowed to be received. On these various grounds, it was argued that the respondents' decision to implement the revised dredging proposals was unreasonable. It was however accepted by senior counsel that the petitioners had no interest in challenging the reasonableness of that decision unless the court accepted that they had a legitimate expectation that the respondents would implement the earlier proposals described in Arch Henderson's report of January 2003 and Mr Manson's e-mail of 9 January 2004. It was also accepted that the arguments relating to the ELP reports involved issues of fact (including issues of which the respondents had no prior notice) which could not be resolved at the first hearing, and which would not arise unless the petitioners first established that they had the legitimate expectation for which they contended. In those circumstances, it was agreed that the court should not consider those matters at present, but would deal with them later in the event that the petitioners succeeded in establishing that they had the legitimate expectation for which they contended. If they did not so succeed, the petition should be refused.
The respondents' case as pleaded
 In their answers, the respondents aver that they had made it clear to the petitioners from the outset that they would require at least 160m clear width (or a span of at least 180m, if the measurement was taken between the centres of the piers). They also refer to the parties' communications with each other between December 2003 and June 2004, and aver:
"As a result of the foregoing the first respondents reasonably believed that the design of the bridge was not fixed and that the petitioners were seriously considering the possibility of increasing the distance between the central piers. ... The petitioners were well aware that the first respondents had never accepted that the centre span of the bridge was wide enough to accommodate their dredging proposals as they stood in January 2004 or their revised proposals as they evolved during 2004" [Ans 8].
It is unnecessary to note the respondents' other averments, which were reflected in their submissions.
The submissions for the respondents
 On behalf of the respondents, counsel submitted that the present case had a number of unusual features. First, it was unusual for one public authority to argue that it had a legitimate expectation as to the future performance by another public authority of its functions. Secondly, where a legitimate expectation existed, the connection between the exercise of its functions by the public authority which had induced the expectation, and the benefit to the other party if the expectation were fulfilled, was normally direct: the expectation was, for example, that the public authority would grant the other party a licence, or allow the other party to continue living in a nursing home, or accept a late application by the other party for tax relief. In the present case, the connection was indirect and contingent. In exercising their power to dredge the harbour, the respondents were not exercising any function in respect of the petitioners. The petitioners would not necessarily benefit from the respondents' abiding by the alleged representation: the petitioners had to succeed in their various statutory applications before they could build their bridge. The party they sought to bind - the respondents - had made it clear since at least January 2004 that they would oppose those applications. The petitioners were thus arguing that the respondents had bound themselves to preserve intact an area of seabed in order to allow the petitioners to build a bridge to which the respondents had made clear their opposition. This was inherently implausible. In reality, the case concerned a failed negotiation. When negotiations broke down, one party did not normally have an alternative means of binding the other, by saying, "In the course of the negotiations, I identified what I regarded as the most important aspect of your position, and decided to make my plans on the basis of affording you that. I was entitled to expect that you would do nothing to prejudice my plans." There was an issue of reciprocity.
 The starting point was that the petitioners were seeking to interdict the respondents from dredging the seabed in the areas where they proposed to construct the pier structures of the proposed bridge. To succeed, the petitioners must demonstrate that they had a substantive legitimate expectation that the respondents would not dredge those areas of the seabed, and that the roads scheme was prepared in reliance on that expectation.
 The representation which the petitioners had to establish was that, if the respondents carried out dredging works, they would not dredge beyond the 120m channel shown in the Arch Henderson drawings. It was the negative commitment which mattered to the petitioners. They were not seeking to hold the respondents to a commitment to carry out any dredging works. What mattered to the petitioners was that if dredging works were carried out, they must be only the dredging works shown in the Arch Henderson drawing. The problem had arisen because the channel shown on the drawing had been widened and rotated. Had the respondents precluded themselves from exercising their power to dredge those additional areas?
 Furthermore, the respondents had to have committed themselves not to carry out dredging works in those areas of the seabed for a period of time which, at its minimum, was however long it took for the statutory consents process to be concluded, and at its maximum (if the consents were to be granted) was for as long as the bridge was in place. The necessary representation was therefore that the respondents had committed themselves not to dredge those areas of the seabed for the indefinite future.
 The representation was said to be derived from five sources. The first was the Arch Henderson report of
January 2003. The report had been
commissioned by the respondents in order to obtain advice about the impact of
the proposed bridge on the future design and operation of the port. The respondents had provided the petitioners
with a copy of the report, so as to make them aware of the advice the
respondents had received. The purpose of
the report was not to give the petitioners a commitment as to the respondents'
future actings. The petitioners' e-mail
 The second source was communications during 2003, as agreed by joint minute. Those did not advance the petitioners' case: all they showed was that no other dredging proposals were being considered in 2003.
 The third source was the e-mail of
 The drawing attached to the e-mail showed the position of the proposed channel, and also of the proposed side slopes. The most that could be taken from those statements (leaving aside the issue of the authority of Mr Manson to bind the respondents) was that the dredging works in the respondents' thinking at that time were those shown on the drawing. There was nothing in those events to commit the respondents to refraining from dredging other areas of the seabed for the indefinite future. Furthermore, the design of the bridge allowed no space for the side slopes or the berms which the respondents had included in their requirements. It was all very well for the petitioners to say that the respondents did not require berms or slopes: the petitioners could not claim to have relied on the respondents' stated intentions, and at the same time say that they had relied on advice that what the respondents proposed to do was unnecessary.
 Two other points were made in relation to the e-mail. The first related to the informality of the communication. It was not established that anyone from the respondents had seen the attachment. In any event, was it seriously suggested that one could found a legitimate expectation on a matter of such significance on the fact that an official of the respondents was copied in on an e-mail? Secondly, following the e-mail, throughout the Spring of 2004, the petitioners continued to paint a picture of willingness to accommodate the respondents' concerns and of flexibility in the design of their bridge.
 The fourth source was Arch Henderson's letter of
 The fifth source was Mr Sandison's e-mail of
 There was also an issue of vires. On any view, the time for which the respondents were alleged to have committed themselves was an indeterminate period. It would be ultra vires for them to commit themselves indefinitely not to exercise their statutory power to dredge a particular area of the seabed. The respondents had to preserve the option of following the best advice available regarding what dredging should be carried out in the interests of navigation. The petitioners were themselves a public authority, and in particular a harbour authority with similar statutory responsibilities. The petitioners could not therefore have had a legitimate expectation that the respondents would proceed with their original proposals regardless of any change in the requirements of the harbour or in the advice which the respondents might receive.
 There was also an issue as to the authority of employees of Arch
Henderson to commit the respondents on matters of policy. What had the respondents done to clothe Mr Manson
or Mr Sandison with the authority to commit them on such issues? The same point arose in relation to the
 Finally, it did not appear to be disputed that, in the circumstances of the present case, detrimental reliance had to be shown in order for the petitioners to succeed on the basis of legitimate expectation. The petitioners had a difficulty, in that reliance must post-date the representation. Here, the statutory consents process began with the submission of the planning application in December 2003, based on drawings prepared in October 2003. Those drawings showed a main span of 160m between pier centres, unchanged since the original Halcrow report in 1999 set out a box girder bridge at Point of Scotland with a main span of 160m as one of the options. The inclusion of that dimension in the planning application was the final significant decision by the petitioners about the main span of the bridge and, therefore, the last action by the petitioners about the main span of the bridge. As at that time, however, there was nothing emanating from the respondents regarding their dredging proposals which could be said to satisfy the requirements for a representation. The petitioners had attempted to meet this difficulty by characterising as the reliance the submission of the roads scheme. For that to constitute detrimental reliance, it would be necessary for the petitioners to show that they would otherwise have acted differently in relation to the roads scheme. They had failed to do so. It was inconceivable that a roads scheme could have been submitted which was at odds with the planning permission granted one week earlier. The dimensions of the main span in the roads scheme were settled when the planning application was submitted in December 2003.
 The petitioners' decision to apply for statutory consents for their chosen design was not a step which they took because they had secured a commitment from the respondents. It appeared to have been taken because they were endeavouring to meet a tight financial and political timescale. They chose to proceed before they had secured the agreement of the respondents to an overall scheme for the two developments.
 In assessing the issue of reliance, the court should take into account that the petitioners' conduct in the autumn of 2004 did not suggest that they believed that the respondents had already committed themselves to a particular channel: when the respondents indicated that they were reviewing their proposals, and, later, that under the new proposals the position of the west pier would be in the dredged channel, the petitioners did not assert that the respondents had already committed themselves and were not entitled to alter their proposals. The first allegation of any sort of commitment by the respondents was the statement in January 2005 which referred to their having entered into a "formal agreement".
 Moreover, a substantive legitimate expectation could not be based on reliance on only one part of a composite message. It was not unfair to the petitioners, if they acted on only part of what they were being told and chose not to comply with the remaining part, if the respondents then changed their minds. The petitioners had never made it clear to the respondents that they were interested in only one piece of information (namely, the channel width), and had never made it clear how that piece of information was going to be used. Furthermore, at the time of the supposed reliance, the petitioners knew that they had to apply for a works licence, to which third parties were entitled to object, and that the respondents were under a duty to consider any such objections, and had a power to require the modification of the petitioners' plans, including the positioning of the central piers. They could not reasonably proceed on the basis that the respondents' position was immutable.
 In support of these submissions, counsel cited (in addition to the authorities cited on behalf of the petitioners) Oswald v Ayr Harbour Trustees (1883) 10 R 472, (1883) 10 R (HL) 85, Birkdale District Electricity Supply Co Ltd v Southport Corporation  AC 355, R v Inland Revenue Commissioners ex parte Unilever plc  STC 681, Docherty v City of Edinburgh Council 2005 SC 598, R (Ghartey) v Secretary of State for the Home Department (2001) EWHC Admin 199,  1 PLR 145, R v Falmouth & Truro Port Health Authority ex parte South West Water Ltd  QB 445, South Bucks District Council v Flanagan  EWCA Civ 690,  1 WLR 2601, R (Association of British Civilian Internees: Far East Region) v Secretary of State for Defence  EWCA Civ 473,  QB 1397 and R (Nadarajah) v Secretary of State for the Home Department  EWCA Civ 1363.
 I note that the submissions of counsel for the respondents did not raise the issue of the compatibility of the petitioners' design with the respondents' requirements in relation to the air draught between the surface of the water and the underside of the bridge.
The legal background
 The discussion before me was concerned principally with the law concerning legitimate expectations and its application to the facts of the present case, although I was also, at my request, addressed on the case of Oswald v Ayr Harbour Trustees. It appears to me to be necessary to begin by considering the law relating to the sea and to harbours, in order to understand the legal context in which any legitimate expectation would have to arise.
 The seabed around the Shetland Islands, including the solum of the Sound of Bressay, is vested at common law in the Crown, by virtue of the prerogative (Shetland Salmon Farmers Association v Crown Estate Commissioners 1991 SLT 166; Smith v Lerwick Harbour Trustees (1897) 5 SLT 175). Under the common law, the rights of the Crown are subject to public rights of navigation and fishing (Crown Estate Commissioners v Fairlie Yacht Slip Ltd 1979 SC 156, per Lord President Emslie at page 169). By virtue of those public rights, members of the public have a title to object to the erection of the piers of a bridge in navigable waters, where the piers would interfere with or obstruct navigation (Orr Ewing & Co v Colquhoun's Trustees (1877) 4R (HL) 116). It has been doubted whether the Crown can convey rights in the seabed which would interfere with such public rights, without the sanction of Parliament (Lord Advocate v Wemyss (1899) 2F (HL) 1, per Lord Watson at page 8; Agnew v Lord Advocate (1873) 11M 309), although the contrary view has also been expressed (e.g. in the Shetland Salmon Farmers case).
"Other things, though they be of their own nature capable of property, are exempted from Commerce in respect of the uses to which they are destined. Of this last kind are, first, the res publicae of the Romans which were common not to all mankind, but to the state or community; such as navigable rivers, highways, harbours and bridges etc., the property of which belongs to the state or kingdom in which they lie, and their use to all the subjects or members of that kingdom, and to those strangers to whom it allows the liberty of trade, not only rivers themselves, and their bed, or alveus, but their banks also, are public, in so far as they may be subservient to the purpose of navigation.
All the subjects which were by Roman law accounted res publicae are, since the introduction of feus, held to be inter regalia or in patrimonio principis as rivers, free ports, and highways ... But as the regalia of this sort are little capable of property, and chiefly adapted as the public use, the King's right in them is truly no more than a trust for the behoof of his people".
Although that passage refers to feudal law as the basis of the Crown's right, it appears from the Shetland Salmon Farmers case that the same result would be arrived at in Shetland (where landownership is based on udal, rather than feudal, law), although on a different basis.
 This position under the common law forms the background to the
legislation of the late eighteenth and, more particularly, the nineteenth centuries,
constituting harbour trustees for the management and improvement of public
harbours. One example of such
legislation is the 1877 Act constituting the respondents' predecessors. Another is the legislation which was at issue
"whether the defenders, as statutory trustees or commissioners, can bind the trust which they administer by an obligation to refrain in all time coming from using for certain harbour purposes ground which they have by compulsory purchase acquired for harbour purposes".
That question was answered in the negative by the Court of Session. Lord President Inglis, in whose opinion Lord Justice Clerk Moncreiff and Lord Mure concurred, emphasised the background of public rights, and the public interest involved in the fulfilment by the harbour trustees of the statutory purposes of their trust. In that connection, the Lord President observed (at pages 481-482) that
"the defenders are nothing but Parliamentary Commissioners for managing and improving this harbour, which, but for the provisions of these Acts, or some previous grant, would, like other res publicae, remain vested in the Crown for the benefit of the nation.... In the exercise of their powers they are merely the commissioners or agents of the Crown and of Parliament, and the statutes constitute their mandate, the terms of which they must implicitly follow.... Neither have they any power after acquiring land for harbour purposes to erect servitudes over it in favour of adjoining landowners or others, or to make or save money by giving to private parties such an interest in the land as will prevent its being applied in time coming to any of the harbour purposes for which at any time, however distant, it may come to be required".
"Section 10 is permissive in this sense only, that the powers which it confers are discretionary, and are not to be put in force unless the trustees are of opinion that they ought to be exercised in the interest of those members of the public who use the harbour. But it is the plain import of the clause that the harbour trustees for the time being shall be vested with, and shall avail themselves of, these discretionary powers, whenever and as often as they may be of opinion that the public interest will be promoted by their exercise."
 In the later case of Birkdale District Electricity Supply Co v Southport Corporation, where the circumstances were very different, the decision in the Ayr Harbour Trustees case was distinguished, but without questioning what the Earl of Birkenhead described (at page 364) as
"a well established principle of law, that if a person or public body is entrusted by the Legislature with certain powers and duties expressly or impliedly for public purposes, those persons or bodies cannot divest themselves of these powers and duties. They cannot enter into any contract or take any action incompatible with the due exercise of their powers or the discharge of their duties".
Lord Sumner explained the decision in the Ayr Harbour Trustees case (at page 371) on the basis that the trustees "were to sterilize part of their acquisition, so far as the statutory purpose of their undertaking was concerned."
 Later authorities (such as British Transport Commission v Westmorland County Council  AC 126) support that approach. Although the courts have not readily allowed public authorities to resile from apparent obligations which have been voluntarily assumed, they have done so where the apparent obligation was incompatible with the authority's core responsibilities. The continuing validity of the principle expressed by Lord Birkenhead is demonstrated by the Ng Yuen Shiu case, where Lord Birkenhead's dictum was cited (at page 638). It is also illustrated, in a context closer to that of the present case, by Rowland v Environment Agency, where it was held that a legitimate expectation could not oblige the respondent authority to act as if public rights of navigation did not exist.
 Turning next to the case law concerned with legitimate
expectations, I was referred by counsel to a large number of authorities in
which a variety of approaches have been adopted. In order to avoid confusion, it appears to me
to be necessary to consider the most important cases in chronological order, so
that the evolution of this rapidly developing area of the law can be
understood. It is also necessary to
emphasise that, although it may be useful for the purposes of taxonomy to treat
the case law on legitimate expectations as forming a distinct body of law, in
reality it is intermeshed with the wider body of public law and depends on
principles of broader application. In a
case with unusual facts, which may not readily fit into the framework or
compartments suggested in some of the cases, it is important not to lose sight
of those broader principles. I should
also note at the outset that the discussion before me proceeded on the basis
that the authorities cited, virtually all of which were English, should be
 When the concept of legitimate expectation was introduced into our public law by Lord Denning in Schmidt v Secretary of State for Home Affairs  2 Ch 149, it was in the context of what Lord Diplock had in Council of Civil Service Unions v Minister for the Civil Service  AC 374 called procedural impropriety: the expression "legitimate expectation" was used by Lord Denning to describe one of the circumstances in which, following Ridge v Baldwin  AC 40, the common law would require a person affected by an administrative decision to be afforded an opportunity to make representations. So understood, the concept was narrower in scope than the concept of the same name which entered our law a few years later as part of the acquis communautaire, and which had its origins in European administrative law, notably in the German concept of Vertrauenschutz: a concept based on the value of legal certainty, with substantive as well as procedural implications.
 In the Ng Yuen Shiu case, the Privy Council treated the concept of legitimate expectation (at page 638) as a "principle that a public authority is bound by its undertakings as to the procedure it will follow, provided they do not conflict with its duty". Over time, however, it came to be accepted that situations in which a public body had created an expectation as to its future conduct could give rise to issues warranting judicial review of the substance of the decision in question. This development took place initially through the widening of the concept of "fairness", introduced into the law in the context of procedural issues, so as to have a substantive content: R v Secretary of State for the Home Department ex parte Khan  1 WLR 1337. In some cases, the issues were also approached under what Lord Diplock had described as the "irrationality" head of judicial review, on the basis that a public body's resiling from an undertaking which it had given, or departing from a policy which it had published, could in certain circumstances be unreasonable or could violate accepted moral standards. The issues were also approached in some cases in terms of the concept of abuse of power.
 The latter approach was applied by the House of Lords in the leading case of R v Inland Revenue Commissioners ex parte Preston  AC 835, which concerned an allegation that the Revenue had gone back impermissibly on its promise not to reinvestigate certain aspects of a taxpayer's affairs. Lord Templeman, giving the leading judgment, said (at pages 866-867):
"In principle I see no reason why the appellant should not be entitled to judicial review of a decision taken by the commissioners if that decision is unfair to the appellant because the conduct of the commissioners is equivalent to a breach of contract or a breach of representation. Such a decision falls within the ambit of an abuse of power for which in the present case judicial review is the sole remedy and an appropriate remedy. There may be cases in which conduct which savours of breach of contract or breach of representation does not constitute an abuse of power. There may be circumstances in which the court in its discretion might not grant relief by judicial review notwithstanding conduct which savours of breach of contract or breach of representation. In the present case, however, I consider that the appellant is entitled to relief by way of judicial review for 'unfairness' amounting to abuse of power if the commissioners have been guilty of conduct equivalent to a breach of contract or breach of representation on their part".
It is apparent that, at that stage of the law's development, the relevant principles of public law were understood as being closely analogous to those of private law.
 Ex parte Preston was followed by the Divisional Court in R v Inland Revenue Commissioners ex parte MFK Underwriting Agents Ltd, where a taxpayer sought to rely upon what was claimed to be an undertaking by the Revenue not to enforce full tax liability in certain circumstances. Bingham LJ noted (at page 1568) that it had not been suggested in Ex parte Preston that the bargain allegedly made would have been a breach of the Revenue's statutory duty, and continued:
"[T]he applicants here accept that they must fail if the revenue could not lawfully make the statements or representations which (it is said) it did. So if, in a case involving no breach of statutory duty, the revenue makes an agreement or representation from which it cannot withdraw without substantial unfairness to the taxpayer who has relied on it, that may found a successful application for judicial review".
His Lordship accepted (at page 1569) that the assurances which the Revenue was said to have given were not inconsistent with its statutory duties. His Lordship continued (at pages 1569-1570):
"I am, however, of the opinion that in assessing the meaning, weight and effect reasonably to be given to statements of the revenue the factual context, including the position of the revenue itself, is all-important .....No doubt a statement formally published by the Inland Revenue to the world might safely be regarded as binding, subject to its terms, in any case falling clearly within them. But where the approach to the revenue is of a less formal nature a more detailed inquiry is in my view necessary. If it is to be successfully said that as a result of such an approach the revenue has agreed to forgo, or has represented that it will forgo, tax which might arguably be payable on a proper construction of the relevant legislation it would in my judgment be ordinarily necessary for the taxpayer to show that certain conditions had been fulfilled ....First it is necessary that the taxpayer should have put all his cards face upwards on the table. This means that he must give full details of the specific transaction on which he seeks the revenue's ruling ...It means that he must indicate to the revenue the ruling sought....It means that the taxpayer must make plain that a fully considered ruling is sought. It means, I think, that the taxpayer should indicate the use he intends to make of any ruling given....Secondly, it is necessary that the ruling or statement relied upon should be clear, unambiguous and devoid of relevant qualification.
In so stating these requirements I do not, I hope, diminish or emasculate the valuable, developing doctrine of legitimate expectation. If a public authority so conducts itself as to create a legitimate expectation that a certain course will be followed it would often be unfair if the authority were permitted to follow a different course to the detriment of one who entertained the expectation, particularly if he acted on it. If in private law a body would be in breach of contract in so acting or estopped from so acting a public authority should generally be in no better position. The doctrine of legitimate expectation is rooted in fairness. But fairness is not a one-way street. It imports the notion of equitableness, of fair and open dealing, to which the authority is as much entitled as the citizen."
 These observations were made in a particular context, that of dealings between taxpayers and the Revenue. The approach adopted by Bingham LJ appears to me however to be of wider application, in so far as it emphasises the importance of paying close attention to the factual context in determining the meaning, weight and effect of statements made by public bodies or officials, and then deciding whether, in the light of those statements, the decision or action in question is unfair and should not be permitted. In that regard, two of the particular matters mentioned by Bingham LJ will usually, if not invariably, be relevant. The first is whether the public body was made aware by the other party of all relevant circumstances: relevant, in particular, to its decision whether to make a representation, to the level within its organisation at which such a decision would be taken, and to the terms in which any such representation would be made. Those circumstances will usually include the use which is to be made of the representation sought. The second matter is whether the representation was clear, unambiguous and unqualified. It has been repeatedly held to be essential to the existence of a legitimate expectation with substantive effects that there should have been a clear and unambiguous representation upon which it was reasonable for the representee to rely. Examples include R v Jockey Club ex parte RAM Racecourses Ltd, R v Devon County Council ex parte Baker, Docherty v City of Edinburgh Council, R v Falmouth & Truro Port Health Authority ex parte South West Water Ltd, R (ABCIFER) v Secretary of State for Defence and Rowland v Environment Agency. It is however necessary to bear in mind, in deciding whether a representation was sufficiently clear and unambiguous to justify reliance upon it, that the representation has to be construed in the context in which it was made, as Lord Hoffmann observed in R (Zeqiri) v Secretary of State for the Home Department (at paragraph 44). It is also necessary to remember that more general principles of administrative law may prevent a public body from departing from its previous position even in the absence of a clear and unambiguous representation, in unusual circumstances such as those considered in R v Inland Revenue Commissioners ex parte Unilever plc, discussed below.
 In the Jockey Club case, the applicant was a racecourse owner who claimed to have a legitimate expectation that it would be allocated race meetings in accordance with a report adopted by the Jockey Club. Stuart Smith LJ, in whose judgment Simon Brown LJ concurred, held that there were five conditions which required to be satisfied in that case before the application could succeed:
(1) a clear and unambiguous representation;
(2) that since the applicant was not a person to whom any representation had been directly made, it was within the class of persons who were entitled to rely on it, or at least that it was reasonable to rely upon it;
(3) that it did rely on it;
(4) that it did so to its detriment; and
(5) that there was no overriding interest which entitled the Jockey Club to change its policies to the detriment of the applicant.
 The five-fold test adopted in the Jockey Club case formed the framework of the petitioners' submissions in the present case: they proceeded on the basis that the court's function at this stage of the present case was to decide whether the first, third and fourth conditions were met (the second condition not being in issue), leaving the fifth condition to be considered, if need be, at a second hearing. In a case such as the present, with a number of unusual features, it seems to me to be necessary to be guided primarily by the general principles of which the five-fold test adopted in the Jockey Club case was merely a particular application.
 In that regard, it is relevant to note the case of Ex parte Unilever plc, which is a rare example of an application based on an expectation induced by a public body succeeding in the absence of a clear and unequivocal representation. The Court of Appeal concluded in that case that for the Revenue to refuse to accept a late claim for loss relief, without prior warning, when for many years previously it had exercised its discretion to accept such claims, would be so unfair as to amount to an abuse of power. Simon Brown LJ observed that, although the absence of an unqualified and unambiguous representation meant that the applicants could not bring themselves within the category of legitimate expectation with which the MFK and Jockey Club cases had been concerned, the broader principle operating in this field was that of irrationality as described by Lord Diplock in the CCSU case. His Lordship continued (at page 695):
"Unfairness amounting to an abuse of power as envisaged in Preston and the other Revenue cases is unlawful not because it involves conduct such as would offend some equivalent private law principle, not principally indeed because it breaches a legitimate expectation that some different substantive decision will be taken, but rather because either it is illogical or immoral or both for a public authority to act with conspicuous unfairness and in that sense abuse its power. As Lord Donaldson MR said in R v ITC, ex p TSW (1992) Times, 7 February:
'The test in public law is fairness, not an adaptation of the law of contract or estoppel'.
In short, I regard the MFK category of legitimate expectation as essentially but a head of Wednesbury unreasonableness, not necessarily exhaustive of the grounds upon which a successful substantive unfairness challenge may be based".
The distinction drawn by his Lordship between the
relevant principles of public law and the private law concepts of contract and
estoppel (or, in
"on the one hand mere unfairness - conduct which may be characterised as 'a bit rich' but nevertheless understandable - and on the other hand a decision so outrageously unfair that it should not be allowed to stand".
The expression "conspicuous unfairness" was adopted also by Lord Hoffmann, with whose speech Lord Mackay of Clashfern, Lord Millett and Lord Rodger of Earlsferry expressed their agreement, in the Zeqiri case, at paragraph 44, and by the Court of Appeal in the ABCIFER case, at paragraph 72. The Court is not, therefore, entitled to intervene on this ground merely because it considers that a decision can be criticised.
 A review
of the previous case law was carried out by the Court of Appeal in R v North
"56. What is still the subject of some controversy is the court's role when a member of the public, as a result of a promise or other conduct, has a legitimate expectation that he will be treated in one way and the public body wishes to treat him or her in a different way. Here the starting point has to be to ask what in the circumstances the member of the public could legitimately expect ...This can involve a detailed examination of the precise terms of the promise or representation made, the circumstances in which the promise was made and the nature of the statutory or other discretion.
57. There are at least three possible outcomes. (a) The court may decide that the public authority is only required to bear in mind its previous policy or other representation, giving it the weight it thinks right, but no more, before deciding whether to change course. Here, the court is confined to reviewing the decision on Wednesbury grounds ...(b) On the other hand the court may decide that the promise or practice induces a legitimate expectation of, for example, being consulted before a particular decision is taken ...(c) Where the court considers that a lawful promise or practice has induced a legitimate expectation of a benefit which is substantive, not simply procedural, authority now establishes that here too the court will in a proper case decide whether to frustrate the expectation is so unfair that to take a new and different course will amount to an abuse of power. Here, once the legitimacy of the expectation is established, the court will have the task of weighing the requirements of fairness against any overriding interest relied upon for the change of policy".
 In relation to that passage, it is important to note in the present case that the only outcome with which either party is concerned is what Lord Woolf described as outcome (c): in other words, the question the court is being asked to determine is whether lawful representations have been made by the respondents which have induced in the petitioners a legitimate expectation of a substantive benefit, which it would be an abuse of power for the respondents to frustrate in the absence of a sufficiently overriding interest. If the court finds, at the stage of the first hearing, that the petitioners have such a legitimate expectation, the task of weighing the requirements of fairness against any competing interest is, as I have explained, to be dealt with at a second hearing. Although that position may not appear clearly from the pleadings, it was made clear in counsel's submissions.
 Returning to Ex parte Coughlan, it will be noted that in the passage quoted above, the court stated that a substantive legitimate expectation could arise as a consequence of "a lawful promise or practice" (emphasis added). The question whether an expectation as to the future conduct of a public authority should have substantive as opposed to procedural effects is another way of asking, first, whether a public authority should be able to bind itself as to its future exercise of its discretion, and secondly, whether such an authority should be able to bind itself to act ultra vires. The Court of Appeal's approach in Ex parte Coughlan, consistently with earlier authority since Ex parte Preston, implicitly answered the first question in the affirmative (to the extent that a public authority may be able to bind itself in certain circumstances), and the second question in the negative.
 Some emphasis was placed by counsel for the petitioners on the case of R v Secretary of State for Education and Employment ex parte Begbie, which was decided by the Court of Appeal shortly after Ex parte Coughlan. The case was cited in support of the proposition that a legitimate expectation could be enforced by the court even in the absence of detrimental reliance. To my mind, however, the case illustrates the importance of detrimental reliance in the type of case with which I am concerned.
 Ex parte Begbie concerned a letter written by the Secretary of State stating that, where a child of primary school age held a place under the assisted places scheme at an independent school providing both primary and secondary education, the child would continue to receive funding under the scheme until the completion of secondary education. Under the relevant statutory provision, such a child was to continue to receive funding only until the end of his or her primary education, unless the Secretary of State decided "in view of any particular circumstances relating to that pupil" that a longer period should apply. A further letter, explaining the statutory position, was sent a few weeks after the first letter. There had been no detrimental reliance on the first letter. An application for judicial review, seeking in effect to enforce the undertaking given in the first letter, was unsuccessful. The principal ground of refusal was that "any expectation must yield to the terms of the statute under which the Secretary of State is required to act" (per Peter Gibson LJ at page 1125). A further ground was the absence of detrimental reliance. Although it was accepted that there were situations where detrimental reliance was not necessary (e.g. where an existing practice gave an individual a legitimate expectation of being treated in the same way as others had been treated, on the basis of consistency), it was said to be "very much the exception, rather than the rule, that detrimental reliance will not be present when the court finds unfairness in the defeating of a legitimate expectation" (per Peter Gibson LJ at page 1124).
"(5) Detrimental reliance will normally be required in order for the claimant to show that it would be unlawful to go back on a representation. This is in accord with policy, since if the individual has suffered no hardship there is no reason based on legal certainty to hold the agency to its representation. It should not, however, be necessary to show any monetary loss, or anything equivalent thereto .....
(6) Where an agency seeks to depart from an established policy in relation to a particular person detrimental reliance should not be required. Consistency of treatment and equality are at stake in such cases and these values should be protected irrespective of whether there has been any reliance as such" (5th edition, page 652).
 The judgment of the Court of Appeal in Ex parte Bibi is also of importance for the general approach which was adopted. The court proposed (at paragraph 19) a three stage approach to all legitimate expectation cases:
"The first question is to what has the public authority, whether by practice or by promise, committed itself; the second is whether the authority has acted or proposes to act unlawfully in relation to its commitment; the third is what the court should do".
The Court observed that the question whether a representation had been made without lawful power would be relevant to the first stage of this approach. The question whether there had been detrimental reliance was regarded as relevant to the second stage; and it was in that regard that the court cited the passage by Professor Craig which was quoted above. It was also at the second stage that other factors relevant to the lawfulness of the public body's decision to adopt a course of action at variance with its previous representation would be taken into account. In that regard, the court observed (at paragraph 40):
"It is in our judgment a mistake to isolate from the rest of administrative law cases those which turn on representations made by authorities".
I respectfully agree.
 The three-stage approach adopted in Ex parte Bibi is a logical way of approaching the problems involved in this type of case. In the present case, however, I was invited to deal with the issue of detrimental reliance at the present stage, as I have explained, and to leave over to a second hearing, if need be, the question whether there was an overriding interest sufficient to justify the respondents' decision. Although the approach I was invited to adopt is different from that adopted in the Bibi case, it has the pragmatic virtue of enabling the court to deal at the present stage with all matters which the parties are agreed can be addressed on the basis of the material presently before the court.
 The case of R (Reprotech (Pebsham) Ltd) v East Sussex County Council is important for its clarification that public law in this area is conceptually distinct from the private law concept of estoppel (or personal bar), the fundamental point of difference being that the public interest in the exercise of public functions, and the effect of their exercise on members of the public who are not parties to the process before the court, require the law to adopt a different approach from that which is appropriate where only the interests of those directly engaged need be considered. In the case, the applicant company had purchased a waste treatment plant in order to use it to generate electricity, following an expression of opinion by the county planning officer that such a use would not involve a material change of use requiring planning permission, and a subsequent resolution by the respondent planning authority which proceeded on the same basis. The planning authority later decided that planning permission was in fact required. On an application for judicial review, the lawfulness of the planning authority's decision was upheld by the House of Lords. Giving the leading judgment, Lord Hoffmann observed that a statutory procedure existed whereby a person could obtain a determination by the planning authority of the question whether planning permission was necessary for a proposed change of use. That procedure had not been followed, but the applicant sought to give the resolution the same effect as a statutory determination. The procedure for making a statutory determination had a number of important features, which included an opportunity for members of the public to make representations, and an opportunity for the Secretary of State to call the matter in for his own determination. Lord Hoffmann observed (at paragraph 29):
"It is, I think, clear from this brief summary that a determination is not simply a matter between the applicant and the planning authority in which they are free to agree on whatever procedure they please. It is also a matter which concerns the general public interest and which requires other planning authorities, the Secretary of State on behalf of the national interest and the public itself to be able to participate".
That passage appears to me to be relevant also to the present case, for the reasons explained below.
 The case of South Bucks District Council v Flanagan was cited by counsel for the respondents as deciding that a legitimate expectation based on a representation made on behalf of a public body only arose if the person making the representation as to that body's future conduct had actual or ostensible authority to make it on its behalf. The case proceeded on a concession, and the issue was not fully discussed. It appears to have been approached on the basis of the law of agency. In other cases involving public authorities, however, it may be necessary to bear in mind the law governing the delegation of statutory powers. A public authority can of course employ agents in the execution of its powers; but the question whether a representation made by an agent (or, for that matter, by an official) is binding upon the authority may raise questions relating to the delegation of discretionary powers. In particular, if a public body cannot lawfully delegate its power of decision-making to a particular person, a purported delegation to that person will be ultra vires, and cannot be rendered intra vires by saying that the person in question had ostensible authority to act as the body's agent. Since the law recognises no legitimate expectation (at present, at least) that a public body will act ultra vires, it cannot, as it seems to me, give effect to a legitimate expectation founded upon an ultra vires delegation. Equally, the law as it stands cannot, ordinarily at least, give effect to a legitimate expectation created by a representation made by an employee or agent of a public authority, even where delegation would be competent, if there has in fact been no lawful delegation, since statutory powers can be lawfully exercised only by the body on which they were conferred, or by a person to whom that body has lawfully delegated the exercise of its powers. There is a somewhat equivocal body of case law concerned with this issue, which is summarised in De Smith, Woolf and Jowell, Judicial Review of Administrative Action, 5th edition, pages 565-569 (and is also considered in Sales and Steyn, "Legitimate Expectations in English Public Law: An Analysis"  PL 564 at pages 577-578) but it was not discussed before me, and it does not appear to be relevant to the present case. Finally, even where there has been a lawful delegation, the representation made by the delegatee can only bind the authority if "it lay within the powers of [the authority] both to make the representation and to fulfil it", as was said in Bibi at paragraph 46. In that regard, I note that there is a debate (reflected in the judgment of May LJ in Rowland v Environment Agency) as to whether the law should be developed so as to allow an ultra vires representation to bind in certain circumstances, as the European Convention on Human Rights may in some cases require. I was not addressed in relation to that debate; and no issue of Convention rights is raised in the present case.
 Finally, the case of Royal Borough of Windsor and Maidenhead v Dewar was cited as a rare example of one public authority seeking to assert a legitimate expectation against another: something which Maurice Kay J expressly assumed (at paragraph 13), but did not decide, was possible. The case is also relevant in that the person who had made the representation did not have authority to bind the body in question. Maurice Kay J treated the question of authority as relevant to the question whether the applicant body could reasonably rely on the representation, stating (at paragraph 13):
"I do not consider it reasonable for a public authority to assume without more that a member, albeit the Chairman, of another public authority with which it is connected is in a position to obligate that other public authority in circumstances such as those prevailing in this case ...[I]t is more difficult for a public authority [than for a member of the public] to resist the suggestion that it ought to have known that the person making the representation had no power to bind his principal".
The present case
 In considering how these legal principles apply to the present case, it is necessary to begin by examining the factual and legal context. The petitioners desired to construct a bridge across the Sound of Bressay. In order to do so, they had to acquire certain land by compulsory purchase, and to obtain planning permission in respect of the landward parts of the bridge and the connecting roads. Since the bridge was to cross directly over a navigation channel within the harbour, and its piers were to stand on the seabed there, with possible implications for public rights of navigation and for the future operation of the harbour, those aspects of the bridge also required authorisation. Such authorisation had to be granted by the respondents, under section 10 of the 1974 Order, or by the Scottish Ministers on an appeal under section 12, subject to the proviso to section 13 (applicable where the works were specifically authorised under any other enactment). One of the effects of such authorisation, in terms of section 10(1), would be to render lawful any interference which there might be with public rights of navigation or other public rights, and therefore to extinguish the right which members of the public would otherwise have had to object to such interference. The petitioners also required the authorisation of their roads scheme under the 1984 Act. The respondents were the primary decision-making body under the 1974 Order, and were also potential objectors to the planning application and the roads scheme. In relation to the latter, an objection by the respondents as the navigation authority would have particularly serious consequences, since it would necessitate the promotion of private legislation.
 As a public authority with ready access to legal advice, engaged in a major project of this nature, the petitioners can be taken to have been aware of the relevant statutory provisions and other relevant legal principles. They would know, in particular, that the 1974 Order laid down in section 10 a statutory procedure whereby a determination could be obtained from the respondents as to whether the piers of the bridge would be permitted to be constructed in particular locations. Before such a determination was made, the petitioners would have to notify the public of their proposal by advertisement, so as to allow objections to be made, in accordance with section 10(2). The respondents would have to take any such objections into consideration before making their determination, in accordance with section 10(3). Just as in the Reprotech case, the petitioners could not obtain a binding determination by the respondents of their entitlement to construct piers in any given location without complying with section 10: they could not, even with the agreement of the respondents, substitute an informal procedure for the procedure required by statute. The same result would also follow from the principle applied in Rowland v Environmental Agency, if the construction of the piers in the locations where the petitioners wished to construct them would interfere with public rights of navigation: those rights could not be extinguished as a consequence of informal representations, but only by following the statutory procedure provided by section 10 (or otherwise by promoting private legislation).
 The question then arises as to what legal effect, in principle, any informal representation by the respondents as to their requirements could have. For the reasons just discussed, such a representation could not bind the respondents to grant a works licence, since they would require to determine any application for such a licence in the light of any objections received. The argument of the petitioners, as I understand it, is that although the respondents could not be bound to grant a works licence, they would nevertheless be bound by what they had earlier said about their dredging intentions, in order to fulfil the petitioners' reasonable expectations: in other words, they would not be bound to allow the petitioners to build their piers in given locations, but they would nevertheless be bound themselves not to carry out dredging works in those locations. I find it difficult to reconcile this approach with the intended purpose of section 10. Section 10(3) provides that the respondents "shall take into consideration any objection". The respondents cannot therefore properly disregard any objection to the works licence application which has implications for dredging requirements in the area where the application proposes that bridge piers should be constructed, on the basis that a previous representation has prevented them from dredging in that area (cf. Stringer v Minister of Housing and Local Government  1 WLR 1281): if the position were otherwise, the respondents would have pre-empted the statutory procedure, and undermined the statutory consultation exercise, by their informal dealings with the petitioners (cf. Reprotech). This point has implications for the petitioners' legitimate expectations. If, in view of the terms of section 10(3), the petitioners could not reasonably expect the respondents to disregard objections which had implications for dredging requirements in the areas where the petitioners proposed to construct the piers, then equally, as it seems to me, the petitioners could not reasonably understand that the respondents had committed themselves to excluding the areas in question from future dredging operations. It would make no sense for the respondents to determine the works licence application on the basis of their current assessment of dredging requirements, if they were at the same time prevented from carrying our dredging on the basis of that assessment, because they were bound by a representation made on the basis of an earlier assessment.
 The difficulty with the petitioners' approach can also be analysed in terms of the principle exemplified by the Ayr Harbour Trustees case. In terms of section 5 of the 1877 Act, the respondents are required to be the "conservators of the harbour", in the public interest. In terms of section 37, their undertaking is to consist of "the improving, deepening and cleansing of the harbour or of such portions thereof as the trustees may in their discretion think fit". For the purposes of that undertaking, the respondents are given more specific powers, including the power under section 9(2) of the 1974 Order to "deepen, widen, dredge, scour, cut and improve the seabed of the harbour". These are necessarily powers of a continuing nature, not to be exercised once and for all by the members of the respondents' board in office at any particular time, but to be exercised by them and their successors in office, from time to time, in accordance with the requirements of the harbour at that time. The harbour includes the locations where the petitioners wish to construct the piers of the bridge. So far as appears from the legislation to which the court's attention has been drawn, the respondents have no power to divest themselves of any part of their undertaking, or to abdicate their responsibility as conservators of the harbour, except insofar as that might be said to be the practical consequence of their decision to grant a works licence under section 10 of the 1974 Order. The latter provision, by empowering the respondents to authorise the construction or placing of works in the harbour, notwithstanding any interference with public rights of navigation or other public rights, might be regarded as enabling them in effect to sterilise part of the harbour as far as certain harbour purposes are concerned, after public advertisement of the application and the consideration of any objections. Subject to that qualification, the respondents are not given any power to determine that any portion of the harbour is to fall outside the scope of their undertaking and is, in particular, to be incapable of being improved or deepened. The implication of the petitioners' argument, however, is that the respondents could bind themselves informally not to dredge certain areas of the harbour for the indefinite future.
 In that regard the submission of counsel for the petitioners was uncompromising: that any information provided to the petitioners by the respondents concerning their dredging plans was implicitly final and immutable, since a bridge is a permanent structure. It has occurred to me that counsel might have advanced a seemingly more modest proposition: that the respondents implicitly undertook not to implement different dredging proposals until the petitioners' various applications had been determined. Such a contention would however raise similar difficulties. The implicit undertaking would, in the first place, be in respect of an indefinite period, which could be expected to last several years but whose duration could not be predicted. Secondly, and more importantly, the respondents would be committing themselves not to exercise their statutory power to dredge the areas in question not only for the period until the petitioners' statutory applications had been determined, but also for an indefinite period thereafter, in the event that the applications were to be granted. That contention, as it seems to me, would raise the same problems as the submission actually made.
 The only substantial point of difference from the Ayr Harbour Trustees case would appear to be that the latter case concerned an undertaking in respect of a part of the harbour which was being compulsorily acquired, whereas the present case concerns an alleged undertaking in respect of existing parts of the harbour. That difference does not appear to me to be material. As in the Ayr Harbour Trustees case, it appears to me that the respondents cannot competently divest themselves and their successors of their statutory powers in respect of areas of the harbour, except to the extent that section 10 permits them in effect to do so. In the language used by Lord Sumner in the Birkdale case, the respondents cannot sterilise (or partly sterilise) part of their undertaking by agreeing informally to exclude areas of the harbour (in particular, parts of the channel through which all vessels entering the harbour from the north must pass) for the indefinite future from the ambit of their statutory powers of improvement and deepening.
 For these reasons, the petitioners' argument appears to me to
encounter fundamental difficulties, even before the facts of the case are
considered in greater detail. On such
consideration, however, further difficulties emerge. Taking matters in stages, the petitioners
have never based their case on anything said or done by the respondents prior
to 2003. That can be readily
understood. When Halcrow first sought
information from the respondents for the purposes of a feasibility study, in
the early months of 1999, they were told that, if a bridge were to be created
at Point of Scotland, the "clear width of channel between supports" would
require to be wider than the navigational channel, because of the need for
vessels to swing sharply at that location.
The clear width requested was either 150m or 160m. Halcrow nevertheless provided designs with a
central span of 125m or 160m, measured between pier centres. Later in 1999 the petitioners sought the
respondents' comments on a span of 125m (notwithstanding a reminder that a
clear width of 160m had been requested earlier), addressing their request to
the Lerwick Port Authority. The
respondents' reply, dated
 In their pleadings, and in the submissions of junior counsel, the petitioners founded on representations said to have been made during 2003. Senior counsel departed from that position, and accepted that the planning application made in December 2003 had not been made in reliance on any clear representation as to the respondents' final position. That appears to me to be correct. So far as the Arch Henderson report of January 2003 is concerned, the contents of the report comprised advice to the respondents from the engineers they had consulted. On receiving a copy of the report, the petitioners acknowledged that the respondents had not adopted any position regarding it. It is also relevant to note that the report recommended a minimum clear width of 160m, depending on side slope stability characteristics to be determined on site investigation. The figure of 160m comprised a dredged channel 120m wide, the side slopes of the channel, and a berm between each side slope and the nearest pier. So far as the remainder of 2003 is concerned, it is agreed that "the only dredging proposals which the respondents were considering carrying out as their next dredging campaign were those contained in the Arch Henderson Report.... and that this was made known to the petitioners" (emphasis added). That agreement does not take the petitioners' case any further forward.
 The next material development was the planning application made
by the petitioners in December 2003. As
I have mentioned, it was accepted in argument on behalf of the petitioners that
the application had not been made in reliance on any clear representation as to
the respondents' final position; and,
for the reasons I have explained, that appears to me to be correct. That is also the implication of the letter
sent by the petitioners to the respondents' chief executive on
"In terms of the design there are a number of options available to adjust pier positions.... [T]he final detail surrounding the outstanding issues can be incorporated in the final design...[T]he Council... have to go forward with a proposal.. and then take on board, as far as possible, amendments to deal with concerns or objections expressed... [T]his letter is sent to advise you of our intentions while giving reassurance that your very real concerns will be fully addressed".
 One implication of that letter was that the drawings accompanying
the planning application did not constitute the final design, and that the
positions of the piers, in particular, could be adjusted. There was also an implicit acknowledgement
that the respondents were known to have concerns about the design shown in the
drawings. Despite the terms of that
letter, it appears from the petitioners' pleadings and submissions that the
design of the bridge was in reality fixed in all material respects once the
planning application was made. It was
explained in counsel's submissions that the location of the central piers was
critical to the design of the bridge and the alignment of the connecting roads,
and that the planning application (which, as explained earlier, was for
detailed planning permission), the compulsory purchase order and the roads
scheme were therefore inter-dependent.
That is reflected in the petitioners' pleadings, which draw no distinction
between "the necessary statutory consents", and proceed on the basis that
detrimental reliance began when "the petitioners commenced their statutory
consents process on
 The planning application itself did not reflect the terms of the respondents' observations on the bridge proposal on 17 November 1999, which had stated the need for a clear width of at least 160m, in the interests of safety. Nor did it reflect the terms of the Arch Henderson report, which had recommended a space of at least 160m between the inner faces of the central pier structures, for engineering reasons designed to protect the dredged channel. The application was in respect of a bridge with a clear width of 134m. The environmental statement which accompanied the application however held open the possibility of the width of the central span being increased after consultation with the respondents.
 The next material development was the meeting held on
"We have also shown the line of the proposed new dredged channel which Lerwick Port Authority wish to carry out."
At the end of the e-mail, Mr Manson asked Mr Craigie:
"Please confirm receipt of this drawing, and the action to incorporate it on all existing and future bridge drawings".
The drawing showed a "120m wide proposed channel" with 10m side slopes to either side.
 Mr Manson's e-mail and drawing appear to me to be consistent with the respondent's position during 2003: that, as agreed in the present case, "the only dredging proposals which the respondents were considering carrying out as their next dredging campaign were those contained in the Arch Henderson report". The e-mail took the matter further, by stating that the respondents wished to carry out that proposal. The e-mail did not however say that the respondents would refrain for the indefinite future from dredging beyond the limits of the proposed 120m channel, or that a bridge design which failed to accommodate the allowance for side slopes shown on the drawing would be acceptable to them.
 For reasons I have already explained, I consider that the
respondents could not give up their power to dredge part of the harbour, in
order to permit a third party to carry out permanent works there, except in
accordance with the procedure laid down in section 10 of the 1974 Order. Even if they had the power to do so, a
decision as to their dredging plans would involve the exercise of their
discretionary powers, notably under section 9(2) of the 1974 Order. The exercise of that discretion could not
competently be delegated to their consulting engineers: a decision under section 9 must be taken by
the authority designated by Parliament, and by no-one else. That principle cannot be obviated by
appealing to the concept of ostensible authority, as previously explained. In any event, an engineering technician
employed by the respondents' engineering consultants would not ordinarily have
ostensible authority to exercise the respondents' power to decide on
appropriate dredging operations. In that
regard, it is material to bear in mind that the petitioners are themselves a
public authority, and indeed a harbour authority. The observations of Maurice Kay J in the Windsor and Maidenhead case, quoted
earlier, appear to me to be apposite:
the present case being a fortiori
of that case, where the representation was made by the chairman of the
authority in question rather than by a third party. The fact that the e‑mail was copied to
the respondents' deputy chief executive does not appear to me to be material,
since there is nothing to indicate that she had any more authority than
Mr Manson to exercise the respondents' power to decide where and when to
carry out dredging operations. The
petitioners knew how to go about obtaining a considered and authoritative
statement of the respondents' position, as their letters of
 It was accepted by counsel for the petitioners that, in considering the significance of the e-mail, it is necessary to have regard to the respondents' objections to the planning application and environmental statement, submitted a few days later. Those objections reiterated that the petitioners' design was unacceptable because the central span was too small; they repeated that there needed to be a minimum of 160m between the inner edges of the pier structures; and they warned:
"This objection pre-supposes pre-dredging of the navigational channel by the applicant. If this is not intended to take place then the minimum 160 metres width referred to will almost certainly need to be increased in order to accommodate potential future development."
The respondents' objections were
reiterated at their meeting with the petitioners' officials on
 Some significance was attached by counsel for the petitioners to the letter sent by Mr Sandison of Arch Henderson to the petitioners' planning department on 13 April 2004. The letter does not however appear to me to advance their argument. It stated that Arch Henderson had been commissioned by the respondents to procure drawings and tender documents for "proposed dredging and land reclamation works". The purpose of the letter was to obtain the planning department's comments on "the proposed works". The enclosed "general drawing for the proposed works" showed a channel which could be measured as being 120m wide. The letter did not indicate that the respondents had decided, or were undertaking, to carry out no other dredging works in the relevant area for the indefinite future; nor, in any event, was the letter sent by the respondents.
 In discussions between the parties' officials, on 21 April and
 The final statement on which counsel for the petitioners founded was the e-mail sent by the respondents' administration manager, another Mr Sandison, to one of the petitioners' officials, Mr Nicolson, on 17 May 2004. The e-mail was sent in response to Mr Nicolson's request for a meeting. Since the suggested date and time were not suitable for the respondents' officials, Mr Sandison wrote:
"In order to assist you in the meantime, I detail below a brief response... that may assist you in the meantime. ... I hope that this information is of use to you in the meantime."
The information was, in short, that "our dredging proposals have not fundamentally changed". This e-mail did not bear to be a formal or definitive statement of the respondents' position. It did not indicate that the respondents had decided to carry out no other dredging works in the relevant area for the indefinite future. There is in any event nothing to indicate that Mr Sandison had any authority to exercise the respondents' power to decide where and when to carry out dredging operations.
 In relation to Mr Sandison's statement, as in relation to the other statements on which the petitioners claim to have relied, it may well be that the petitioners could reasonably have believed that the respondents intended to carry out particular dredging works. That does not however appear to me to be the relevant issue. The question is whether it was reasonable for the petitioners to act on the basis that the respondents had lawfully committed themselves to carrying out particular dredging works and only those works; and therefore, by implication, to not dredging the other areas of the seabed where the petitioners proposed to locate the piers of the bridge.
 One week after detailed planning permission was deemed to have
been granted on the basis of the drawings attached to the planning application,
the petitioners made the roads scheme.
This was relied on by counsel for the petitioners as demonstrating
detrimental reliance on the legitimate expectation supposedly created by the
various statements which I have discussed.
Counsel did not however put forward any basis for establishing
detrimental reliance which was specific to the roads scheme. Counsel did not, for example, have any
information as to the amount of any expenditure involved in the roads scheme. Nor did counsel indicate any respect in which
the design of the roads scheme differed from the design in respect of which the
planning application had been made. So
far as the design was discussed in argument, it appears to have been the same; and the implication of counsel's submissions
about the dependence of the entire design on the location of the central piers
was that the design on which the various statutory applications were based had
been fixed by the time the planning application was made. That is also the implication of the
petitioners' averments referring to "the final design of the proposed bridge in
respect of which the petitioners are now seeking planning consent", and to the
unreasonableness of the respondents' believing "that the design of the bridge
was not fixed... after the statutory consents process had commenced" (the
petitioners having "commenced the statutory consents process on
 The subsequent events can be dealt with relatively briefly. In July 2004 the respondents instructed port
and marine consultants, ELP, to carry out an assessment of the navigational
impact of the proposed bridge. It was
that assessment which led to the respondents' decision to undertake more
extensive dredging than they had been proposing earlier in 2004: something of which they gave the petitioners
 In the circumstances, I conclude that no clear and unambiguous representation was made to the petitioners that the respondents would not carry out dredging works for the indefinite future in the locations where the petitioners proposed to construct the central piers of their proposed bridge; that the individuals whose statements are founded upon could not lawfully have made such a representation on behalf of the respondents; and that a commitment to that effect would in any event have been ultra vires of the respondents, unless it was the corollary of a decision to grant a works licence in accordance with section 10 of the 1974 Order. I therefore conclude that the petitioners can have had no legitimate expectation to that effect. I am also not satisfied that detrimental reliance on any such expectation has in any event been established.
 My conclusion that the respondents' conduct is not in breach of any legitimate expectation of the petitioners is consistent with my broader conclusion, essentially one of impression (as Lord Mustill observed in R v Inland Revenue Commissioners ex parte Matrix-Securities Ltd  1 WLR 334 at page 358), that the respondents' adoption of revised dredging proposals could not be regarded as an abuse of power. It does not appear to me that the respondents have acted with conspicuous unfairness. On the contrary, it appears to me that it would be unjust to the respondents, and would confer an unmerited benefit on the petitioners, if the respondents were compelled to compromise their plans for the future development of the harbour in order to accommodate a bridge design which deliberately failed to meet their stated requirements.
 For the reasons discussed, I shall repel the petitioners' third plea-in-law, relating to legitimate expectation, and sustain the respondents' seventh plea-in-law, which is concerned with the same issue. It was agreed that, in that event, the petition should be refused. I shall accordingly sustain the respondents' fourth plea-in-law (which, as counsel submitted, appears to be the most apt), and refuse the petition.