On 6 April 2018, the State Party submitted a state of conservation report, available at http://whc.unesco.org/en/list/373/documents. The report provides updated information on the proposed A303 improvement within the Stonehenge component of the property, and progress made in implementing the recommendations of the 2015 and 2017 Advisory missions. The report, available at the above-mentioned web address, explains why the southern surface (F10) option has been rejected and why longer tunnel options are not considered feasible.
The State Party position remains that a twin-bored tunnel with dual carriageway approach roads on either side will deliver benefits by removing the surface road from the central parts of the property. In response to Committee Decision 41 COM 7B.56, and feedback received from the State Party’s heritage agencies and other parties, the scheme has been modified and in September 2017, the State Party announced the ‘Preferred Route’ comprising a twin tunnel approximately 3.3 km long, including a short covered section, plus more than 2 km of dual carriageway in cuttings with some land bridges. The eastern portal remains to the east of The Avenue and the western portal is closer to the current A303 alignment, within the property. A 3rd World Heritage Centre/ICOMOS Advisory mission took place at the invitation of the State Party from 5 to 7 March 2018 and was focused on what is now termed the ‘Proposed Scheme’ which was subject to public consultation between February and April 2018. The statutory processes will allow for advice of the Advisory mission and Decisions of the Committee to be considered before a Development Consent Order (DCO) application is submitted.
There is progress with a range of other issues including establishing an independent and sustainable Stonehenge and Avebury World Heritage Site Trust, a study of the setting of the property, within the Local Development Framework and Wiltshire Core Strategy; development of techniques to address the threats posed by cultivation and burrowing animals; traffic strategies for the Avebury component of the property; master planning for the proposed ‘Boscombe Down Development’; and progress with planned army development north of Stonehenge at Larkhill Garrison.
The ’Proposed Scheme’ for the A303 improvement shows improvement compared with previous plans and would also improve the current situation in the centre of the property. Further investigations and assessments have indicated that the F10 southern surface route option is not viable because of a range of factors, including the priority afforded to impacts on Areas of Natural Beauty and Special Conservation Areas.
The 2018 Advisory mission concluded that the rigorous investigation, evaluation, iterative design and assessment process of the project has revealed that, if the tunnel solution is to be pursued, the current length proposed is not adequate to protect the authenticity, integrity and Outstanding Universal Value (OUV) of the property. The best option (in terms of OUV) would be a surface route, which re-routes the A303 completely around the Stonehenge component of the property, and enables the closure of the existing section of the A303 within the property. If a surface route is not possible, a longer tunnel is needed, which removes or at least substantially reduces the proposed lengths of dual carriageway within the property, in order to avoid the impact on the integrity, authenticity and OUV of the property.
The 2018 mission acknowledged that the eastern portal has been positioned in the least impactful location available close to the property’s boundary, given the constraints imposed by the attributes of the property, other significant sites in the vicinity and local topographic and environmental conditions. However, a tunnel portal much further to the east, completely outside the property, could better protect the OUV of the property from the impact of associated dual carriageways. The western portal location involves an intrusive section of cut dual carriageway within the property. Therefore, if a tunnel solution is pursued, the western portal should be re-located outside the western boundary to avoid dual carriageways within this part of the property.
The State Party and its agencies should continue to proceed thoroughly and cautiously, to ensure that the optimal solution is identified and implemented for the widening of the A303. If the ‘Proposed Scheme’ tunnel option is pursued, substantial design refinement should occur and respect for the OUV of the property should take precedence over any predetermined project deadlines. The decision making processes for the project have not yet afforded sufficient priority to avoiding adverse impacts on the OUV of the property, particularly relative to economic and environmental considerations.
The 2018 mission report includes a logical set of recommendations that provide clear guidance for revising the current proposal, management of issues such as archaeology, sustainable tourism, availability of suitable expert advice, community consultation and the evaluation of heritage impact, noting that the State Party and its agencies have made considerable progress. The mission report notes the intentions of the State Party to incorporate a package of ‘legacy benefits’ and recommends that these should incorporate initiatives and programs identified as desirable to conserve and/or interpret OUV in the Plan of Management for the property.