In a bid to protect its World Heritage status, the City of Liverpool and Historic England have drawn up a heritage action plan, created to navigate the threat posed by a proposed development of the city’s waterfront, which could see it struck from the Unesco register.

Granted outline planning permission in 2013, the £5.5bn (US$7.7bn, €6.22bn) Liverpool Waters 30-year development scheme from The Peel Group would “undoubtedly cause substantial harm to the outstanding universal value (OUV) of the World Heritage property”, according to the Heritage Impact Assessment report, which also said that such a development would lead the World Heritage Committee to delete Liverpool from its list.

Among the concerns for the WHC is Everton Football Club’s proposed development of a new stadium at Bramley Moore Dock. While land has been leased, according to the report “no planning application has been submitted, nor is such an application imminent”. The report goes on to say that should the move go ahead, it would be assessed according to the new action plan.

The city will also be clamping down on tall towers, which follows controversial plans to build a duo of high rise buildings overlooking the River Mersey. Designed by Hodder and Partners and Brock Carmichael Architects, the pair of buildings towered over neighbouring sites, which breached one of the Unesco conditions for the city’s World Heritage site. Called the “Skyline Policy”, the new rule would put height caps in place for any new development, so as to protect the city’s skyline from new development.

Responding to a 2015 mission to “ensure urban design guidelines that will provide continued coherence for the architectural and town-planning values and that will be proactive to ensure the management of the World Heritage property and the city centre”, the report also says that the neighbourhood masterplans for Central Docks and for Northern Docks will be guided to ensure that the architectural and town-planning coherence and the conditions of authenticity and integrity of the World Heritage property are sustained.

In the action plan, it is suggested that the city create the Liverpool World Heritage Trust (LWHT) – a body created under a new partnership that would manage the waterfront site and the city’s wider historic environment. As part of this, it is suggested that the property boundaries and buffer zone around the Liverpool Maritime Mercantile City World Heritage Site is extended to “better reflect the maritime and mercantile pre-eminence as the greatest Western European seaport, from the early eighteenth to the mid -twentieth centuries”.

“The detailed plans will integrate all the different dock areas of the property into one continuous historic urban landscape, maintaining the existing horizontal layering of the city profile, expressed as a three-tiered urban structure,” said the action plan.

“To demonstrate the very real progress that is being made to realise this desired state of conservation, the emerging Central Docks neighbourhood plan has initiated a fresh approach, which utilises OUV as a driver for place making.”

According to the report, developer Peel Holdings is currently undertaking a comprehensive review of the development scheme and is drawing up a new masterplan taking full account of heritage considerations including all recorded commentary by the WHC.

The draft version of the action plan is due to go before Liverpool Council tomorrow (23 February). It will then be submitted to the WHC for consideration at its July meeting. Two sites have previously been stripped of World Heritage status – Oman’s Arabian Oryx Sanctuary in 2007 and the Dresden Elbe Valley in 2009.