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ITEM EX13

CORNMARKET STREET, OXFORD

Introduction

1. This report discusses the construction failure of the environmental enhancement scheme in Cornmarket Street, considers possible options for improvement and their impact on the out-turn costs and the programme for the implementation of the scheme. It also recommends the preferred way forward.

Background

2. The County Council’s appointed consultants, Landscape Design Associates (LDA) and Peter Brett Associates (PBA), carried out the design and supervision of construction of the environmental enhancement scheme in Cornmarket Street. Site works commenced early in July 2001 and cracks in the granite block paving began to appear from mid-September onwards. Although several measures were taken by the consultants to see if the cracking could be halted, cracking still continued up to the end of October 2001 when the agreed break for the Christmas shopping was taken.
3. The design consultants called in an independent expert to establish the reason for the failure and to suggest a way forward. Various tests were carried out and a series of interim reports followed, culminating in a final report at the end of January 2002. Because of the complex nature of the failure, the County Council engaged two additional independent experts to advise on the findings in the report. The views of these two experts were received in March 2002 and considered by the officers of the City and County Council, and also passed to the design consultants for information. Meantime further work in Cornmarket Street was suspended. Counsels’ advice has been taken throughout (hence the apparently slow progress) to minimise liability for the County Council given the complex contractual arrangements.
4. LDA have considered the various findings and produced their suggested proposals for the way forward. These proposals formed the basis of a presentation to relevant County and City members at a meeting at County Hall on 26 June 2002. A copy of the slides presented at that meeting is in the Members’ Resource Centre.

Possible Options

5. Three possible options were described in detail at the consultants’ presentation. All three options feature an enhanced specification for the footway and carriageway construction. In broad terms, the distinction between the options lies in the use of different materials for bedding and jointing of the granite blocks, as details for the enhanced footway construction are common to all three. Construction details of the possible options are summarised in Annex 1.
6. Enhanced specification details have a significant bearing on the construction costs of the scheme. The consultants’ estimates of construction costs for them vary between £2.94m for Option 1 to £3.21m for Option 3. These estimates can be compared with an original budget construction cost of £1.96m and the present projected budget of £2.49m, which includes current contractor claims (including for instance those arising from problems with public utilities work) under the existing construction contract.
7. On-site and off-site trials and tests would be required for any of these 3 options. This would significantly delay completion of the work. However, even with the enhanced specification, LDA are unable to give a guaranteed design life for the new construction as the specifications have not yet been tried and tested. It is likely that all options would require the purchase of new granite blocks that are cut to stricter tolerances. Given the new specification, the final granite paving will offer difficulties to re-instatement following any public utility works.
8. The City Council introduced the Public Realm Strategy (PRS) for Oxford in September 2000. The County Council agreed to adopt the principles of PRS for the Cornmarket Street scheme. This strategy, for principal streets with restricted traffic, seeks to have either large granite setts (or blocks) or asphalt with coated granite. Although the PRS indicated that Cornmarket Street should have a paved surface, the use of a flexible surface, as on similar principal streets, would appear to be a reasonable alternative.
9. As the success of the large granite blocks cannot be assured and their use would incur further significant delay, it is suggested that a fourth alternative is considered - Option 4 summarised in Annex 1. This can be implemented without any trials or testing and its construction costs will be cheaper than the other three options. The current estimate of construction costs for Option 4 stands at £2.629m (see Annex 2). The only departure from the City’s PRS guidelines would be the type of surface of the carriageway as it is intended that all the other elements of the PRS relating to the Yorkstone footways and street furniture would be accommodated with this option. This flexible carriageway option has the added benefit of enabling future maintenance repairs (following public utility openings etc.) to be carried out almost seamlessly and with the minimum additional extra costs to the County Council.
10. The estimated date for completion of the three options suggested by LDA is July 2004 as due account has to be taken of the time required to test and trial the new specifications, both off and on site, and the time needed to order and supply the new granite blocks. This assumes that no further delays are encountered during the construction. The work could start in October 2002, subject to the County and City Executives’ decision and agreement of financial contributions. Testing of materials in the laboratory with trials in the contractor’s yard and in Cornmarket would provide results during May 2003. Depending on positive results of the tests and following ordering of new granite blocks, construction could then re-start in July 2003 and last until October 2003 to allow for the Christmas shopping break. It would then re-start again in February 2004.
11. On the other hand, the work on Option 4 could also start in October 2002 but as it would not require any tests or trials, works could be completed in July 2003. This would still include a similar Christmas break as in the other three options.

Scrutiny Committee Views

12. The Environment Scrutiny Committee considered the position in the light of a report on the LDA/PBA presentation (which some of the members had been able to attend). At the invitation of the Chair and Deputy Chair of the Committee, members of the City Council’s Environment Overview & Scrutiny Committee also participated in the discussion.
13. Following a lengthy debate, the Committee agreed "to recommend the Executive to seek to pursue in partnership with the City Council the option of an asphalt carriageway surface, as offering the least risk in terms of capital cost, performance, and future maintenance liability, with consideration given to textured surfacing, trees and appropriate street furniture and investigation undertaken for the longer term of the possibility of a weight limit in the street"

Financial Contribution Agreement

14. The County and City Councils have previously entered into a legal financial agreement that specifies the duties and responsibilities of both councils in relation to the implementation of the Cornmarket environmental enhancement scheme. This agreement sets out the details of the scheme, the delivery dates of various construction phases and also the level of financial contributions; the City Council’s contribution towards the implementation of the scheme is currently standing at £1.855m.
15. Any departure from this agreement, including changes to the original specification, requires formal approval by both Councils. The current agreement specifies 31 July 2002 as the scheme completion date. Option 4 represents some departure from the original design and it therefore needs to be agreed with the City Council. It is possible that the City Council would wish to re-negotiate the present legal agreement and amend the level of financial commitments that it wishes to contribute towards the revised scheme. The implementation of Option 4, or indeed any other option specified by the consultants, depends therefore on both the City and County Councils approving amendments to the existing agreement and on the level of financial contributions by the City Council.

Way Forward

16. Having reviewed the options recommended by the LDA and taking into account the high out-turn and maintenance costs, uncertainties and risks associated with necessary trials and tests, and the impact of the construction time on the overall scheme delivery programme, I cannot recommend any of the three granite options for implementation.
17. I have also considered the possible scenario of the City Council not agreeing to any modifications to the scheme that did not adhere to the full PRS standards (Option 4). In that situation, the City Council might choose to abandon the scheme altogether and to withdraw their financial contributions. The only option available to the County Council would then be to introduce a standard highway scheme of black tarmac for the carriageway surface and concrete paving slabs for the footway area.
18. It is therefore my view that the only viable option that would bring the best outcome for the County and City Councils is the implementation of Option 4 and the swift settling of the Financial Contribution Agreement between both Councils.
19. The City Council’s Executive will consider its position in relation to the available options at its meeting on the 22 July 2002. We have made all our information available to City officers to advise the City’s Executive Board. I hope to be able to report orally the outcome of that meeting to this Executive. Following the meetings of the respective Executives there may be a need for a further joint meeting in August 2002 where any supplementary information can be provided.

Environmental Implications

20. The continuation of the environmental enhancement of Cornmarket Street in accordance with the City Council’s Public Realm Strategy principles will make a major contribution to the visual amenity of the city centre and provide a safer and more attractive environment for pedestrians.

Financial Implications

21. It is difficult, at this stage, to calculate accurately the total out-turn costs for implementing any of the possible options. However, a summary table of the costs as can be best estimated at present is included in Annex 2. These estimated figures show that the cost of implementing Option 4 stands now at £3.279m. On the assumption that the City Council’s contribution stays the same, the remaining balance is £1.424m. Taking into account the County Council’s original budget of £460k, it brings the remaining balance to £964k. However, the County Council will pursue through appropriate legal procedures costs attributed to the failure of the construction. At this stage a reasonable assumption might be that the abortive costs and fees which the County Council would claim are in the order of £600k. On this basis the remaining cost would be approximately £364k. This covers non-abortive work necessary for any improvement scheme and justifiable claims mainly associated with the public utility work.
22. The total out-turn cost to the County Council depends on the amount of the City Council’s financial contributions based on the Public Realm Strategy elements of the scheme. It is possible that the City Council might seek to suggest that it should modify its current contributions, in the case of Option 4, to reflect the reduction of the PRS elements of the original scheme, and expect the County Council to balance this additional shortfall. (The scenario in paragraph 17 above is an alternative option available to the County Council).
23. The proportion of the increased implementation cost associated with Option 4 that would require funding during this financial year would need to be accommodated by reallocation of funds for the 2002/03 capital programme. The remaining proportion of these costs would need to be set aside in the 2003/04 programme still to be agreed by the Executive.
24. The decisions reached by the Executive and the City Council’s Executive Board will determine the future of the Cornmarket Street scheme. What determinations will be necessary as to financial provision by the County Council (including a project appraisal in respect of the expenditure, if appropriate) will depend on those decisions, and specifically on which option is chosen for implementation.

RECOMMENDATIONS

25. The Executive is RECOMMENDED to approve in principle a revised environmental enhancement scheme for Cornmarket Street based on Option 4 described in the report, subject to:

1. completion of an agreement between the City Council and the County Council providing for financial arrangements for meeting the costs of the scheme in a manner satisfactory to the Director of Environmental Services and Solicitor to the Council, following consultation with the Executive Members for Transport and Strategic Planning & Waste Management and in the light of any further meetings with the City Council;
2. subsequent determination of the funding within the capital programme 2002/03 and 2003/04 of the County Council’s share of the costs of the scheme under the financial agreement;
3. the detailed scheme layout for implementation being agreed by the Director of Environmental Services in consultation with the Executive Members for Transport and Strategic Planning & Waste Management.

DAVID YOUNG
Director of Environmental Services

Contact Officer: Dariusz Seroczynski Tel: Oxford 815629

July 2002

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