Tiny snails which hold key to A47 work moved, but five year study now needed

The Acle Straight. Pic: Nick Butcher (Image: Archant © 2017)

But it will still be five years before it becomes clear if their relocation can pave the way for work.

However, campaigners are optimistic funding for a scheme could be awarded before the studies end.

Dykes around the road are one of the few habitats of the Little Whirlpool Ramshorn Snail - which is on an international 'red list' of endangered species.

Because the miniscule molluscs are so rare, they are protected by law, so Highways England has to ensure any work does not threaten them further.

In 2016, they started a process to move 800 snails away from the dykes by the side of the road to another part of the marshes.

A follow-up survey indicated the snails, which have shells less than a fifth of an inch in diameter, had survived the switch and were breeding, so an even larger number was moved last year.

And this year, a similar number of the gastropods were moved.

However, they need to be monitored for five years before the switch can be declared a success - and that study is not due to conclude until 2023.

Until then, it would not even be possible for safety barriers to be installed alongside the dykes, let alone dualling the road, which campaigners have been demanding for decades.

A spokesman for Highways England said: 'Environment surveys revealed the rare and protected Little Whirlpool Ramshorn Snail made its home in ditches alongside the Acle Straight section of the A47, meaning they will need to be successfully relocated before any future scheme can be considered along this section of road.

'We are currently undertaking a translocation project and early indications suggest the translocation of these rare snails has been successful and we'll continue to monitor them in their new location for a number of years to come.

'The A47 remains an important route for Highways England, and we will continue to assess where improvements are needed and can be delivered in an environmentally responsible way.'

While millions of pounds of work is due on the A47, the Acle Straight dualling was not included.

And, in a Highways England vision for work from 2020 to 2025, that section was not flagged up as anything other than a standard trunk road, sparking concern it could miss out again.

But a spokesperson for the A47 Alliance, which brings together councils, businesses, MPs and other stakeholders, said: 'We think these results are really encouraging for the prospect of getting the Acle Straight dualled.

'The relocation of the snails is something that needs to be resolved before any work on this stretch of road can start, so this study is paving the way for these improvements.

'And we believe the timescales for the study would still allow the Department for Transport to finance dualling of the Acle Straight from their next round of funding.'