BLACK FRIDAY EVENT

THE Cornish hedges which have collapsed a few months after being built as part of the £330 million A30 dualling scheme were not constructed the right way, National Highways has admitted.

Three kilometres (1.8miles) of Cornish hedges have been erected so far along the newly reopened A3075 as part of the huge infrastructure project.

However, large sections of hedges between the Chiverton Cross roundabout and the first Perranporth turnoff have either collapsed already, or are about to fall apart, leaving great big scars in the hedge.

Many people, including professional Cornish hedgers, have criticised National Highways’ contractors for building the hedges more like dry stone walls rather than in the traditional manner, which should have ensured they withstood the test of time rather than fall apart after a few weeks.

A good Cornish hedge as seen all over Cornwall can endure for hundreds of years if well built. Some in west Penwith are believed to be 1,500 years old and are still standing. As an integral part of the road upgrade, contractor Costain is meant to be building a total of eight miles of traditional Cornish hedges alongside the new route near Truro and will be restoring existing ones too. Earlier this year Costain said the Cornish hedges were being built following guidelines set out in the Guild of Cornish Hedgers’ bible ‘Building Hedges in Cornwall’.

However, after the WMN’s sister website CornwallLive reported on the fiasco and brought it to their attention, National Highways has now admitted that the Cornish hedges along the A3075 Newquay Road were not done properly – and that they did not follow the ‘design guidelines’ – which is why they have collapsed, or are on the verge of collapsing after the first month of rain.

Particular to the Duchy and dating from the Neolithic period – dating back to 1,500 BC – Cornish hedges are traditionally five-foot high, stone-faced earth hedgebanks with bushes or trees growing along the top. In this particular case, stone material is being reused from existing sections of hedging which are being dismantled to make way for the new route.

National Highways is creating nearly nine miles of dual carriageway to unlock congestion on the single carriageway section between the Chiverton Cross and Carland Cross roundabouts. Many people have commented that the Cornish hedges have been built by drystone wallers who haven’t built Cornish hedges before, and are being built too tall and too narrow, despite guidance and training from members of the Guild of Cornish Hedgers.

We drove past the area where new Cornish hedges have been built between Chiverton Cross and the Perranporth turn-off, and within a stretch of just less than a mile, there were at least 20 separate sections of collapsed stone. The soil bank behind the stones is now apparent and slowly washing away down in the rain. Where the ‘walls’ are still standing and if they have been built correctly they look solid and straight. When not built following the proper guidelines you can seen great big bulges trying to bubble out of the walls where the soil behind is pushing through. These, if not repaired or redone, will collapse soon.

According to the Guild of Cornish Hedgers, a good Cornish hedge is wider at the bottom than at the top, because of the large “grounder” stones at the base. If built properly, the structure is very stable and will stand for a hundred years or more.

The hedge has two stone faces with soil between the two walls.

Bushes such as gorse may grow on the top, rooted in the soil between the walls. It is called a ‘hedge’ rather than a wall because of its living component. The Guild also explained that Cornish hedges are built with a steep gradient at the bottom and slightly less steep at the top, with large stones forming the base of the hedge and stones going over well compacted earth forming the bank.

Over time there might be some slight inward collapse from the top section which should strengthen the structure altogether as it compacts the whole structure down.

Patrick Semmens, chairman of the Guild, said his report on the collapsing hedges has now been passed on to contractor Costain.

A spokesman for National Highways said: “With our delivery contractor Costain we have identified a number of defective and weather damaged sections within the programme of work, including the hedging alongside the newly reopened A3075, which did not follow the design guidelines.” They continued: “We are still analysing timescales for the remedial work, which will be managed and monitored by Costain, and the work will not have an impact on the project’s open to traffic target of winter 2023.”

Nick Simmonds-Screech, National Highways project director for the A30 Chiverton to Carland Cross scheme, added: “Sub-contractors will be rebuilding the defective and weather-damaged sections of hedging and this work will not increase the overall project cost.”

‘We’ve identified a number of defective sections... which didn’t follow design guidelines’ NATIONAL HIGHWAYS