Bristol Water has confirmed its £27 million Southern Resilience Scheme will not be complete by March this year as improvement works have been delayed due to roosting bats.

Part of a popular cycle path in North Somerset – the Strawberry Line Cycle way – will remain closed for the foreseeable future as the water company aims to reinforce the water supply to 280,000 customers in the region.

The route is currently diverted in the Winscombe area including a diversion around Shute Shelve Tunnel.

Work has been going on for more than a year with completion originally set for March 2018, but due to the delay caused by the winged-mammals the water company has decided to maintain the diversion.

A spokesperson from Bristol Water, said: “We are aware of the significance of the tunnel to the local area and our intention had been to reopen the tunnel for the summer period. Unfortunately, our work has been delayed and, following discussions with the Strawberry Line Management Committee and North Somerset Council, the tunnel will remain on its temporary diversion until further notice.

Bristol Water said there was a minor rock fall within the tunnel when work began in October 2016, which meant work had to be suspended while an investigation was carried out and a safe working plan was devised.

However, after the initial setback the work was suspended again because of bats roosting in the tunnel.

The spokesperson added: “We have made significant improvements to the safety netting to ensure the tunnel’s ongoing safety once our work has been completed.

“Unfortunately, our work on the safety netting had to be suspended due to the presence of roosting bats.

“We have worked with Natural England and North Somerset Council on measures to prevent bats from roosting in the tunnel whilst works were ongoing, but these measures have not been effective.”

The environmental issues led the company to decide to complete as much of the work as possible before the bats began their hibernation cycle in October 2017.

Bristol Water’s spokesperson, said: “The Strawberry Line and tunnel habitats are important sites for bats and many other species of flora and fauna; therefore, we are endeavouring to minimise our impact on the natural environment.

“We wish to leave it in a condition that is as good, if not better, as when we started.”

The company is also trying to protect the stalagmites and stalactites in the tunnel, as well as cave spiders.