People concerned about the potential damage to the iconic waterfall of Rhaeadr-y-Cwm above Llan Ffestiniog are invited to see this natural wonder for themselves and hear from experts why this landscape and its wildlife are so special and how these qualities could be damaged if the proposed hydro scheme were to go ahead.

They are invited to a free walk down part of the Eryri Slate Trail at 10.30am on Saturday, 14 February, St Valentine’s Day, from the Cwm Cynfal park park ( What3Words: ///blotches.rebel.inversely. Grid Reference: SH 7346 4176).

A planning application had been submitted for a small hydro electric scheme, which conservationists say could nevertheless do huge damage by diverting, at times, nearly 70 per cent of the water out of the waterfall, thus changing the conditions for the damp-loving plants, whose presence is one of the key reasons why the site is designated as a Site of Special Scientific Interest.

The scheme was to have been decided by the Eryri National Park Authority in January with a recommendation for approval.

However, the Welsh Government has now put a temporary halt on this as it decides whether to “call in” the application.

The walk on 14 February is free, will be around four miles long over rough ground and includes a free tea and cake at the bottom of the Cwm. It is being organised by the local group Caru Cwm Cynfal.

Group member Rory Francis said: “Welsh Planning Policy is clear that development should only be allowed designated wildlife sites like this where there are ‘wholly exception circumstances’, which clearly do not exist in this case.

“We need to decarbonise, but the amount of energy this scheme would generate would not make a significant difference. You would need 12 schemes like this, on 12 rivers, to generate as much electricity of just one modern 7.2MW wind turbine.”