The Afon Cynfal is threatened by development, again.

UPDATE: The Environmental Impact Assesment Survey closed on 25/11/2023.

In 2019 we ask you, our community, to help us protect one of the most iconic landscapes in Wales the waterfalls cascades of the Afon Cynfal (Site of Special Scientific Interest – SSSI) were threatened by a proposed hydroelectric development that would dam and divert water around falls.
Thanks to your support, and the objections of Save Our Rivers and the Snowdonia Society, this stunning location was preserved.

The Snowdonia National Park Authority placed the application for the Cwm Cynfal hydro scheme on hold. The planning department rightly decided that the application submitted was inadequate for such a potentially damaging development and a full EIA (Environmental Impact Assessment) was requested.

This EIA has now been submitted, but despite the extra survey information, the scheme remains largely unchanged from the 2019 application, and our original objections still stand. 


The proposed development has multiple concerns including the visual impact of the intake structure, the damage to the ecology of the river and bog area around the river crossing and the permanent landscape changes required to underground the pipeline along the Slate Trail.

There are significant risks during construction of damage to the downstream SSSI which are not adequately addressed in the CMS.

It is felt that the proposed development should be rejected as the low level of power produced does little to offset the impact to both the ecology and aesthetic of this culturally important landscape and to compensate for the fragmenting of one of the UKs last remaining free-flowing rivers.

You can read the latest information from the developer here:

You can read our full objection to the 2019 application here:

As part of the EIA process the developer is required to seek public comments on the application, we need you to show your concerns and fill a survey. This closed on the 25th of November, and we are grateful to every single one of you who took the time to read through the information and share your thoughts on the Cynfal. We await the developer's next move.... 

More Information
Cwm Cynfal is one of the wildest and most inspiring landscapes within Snowdonia and indeed the UK. Towering waterfalls cascade from the bleak beauty of the Migneint Special Area of Conservation into the Afon Cynfal Site of Special Scientific Interest. This unique place has a history of inspiring those that visit from the ancient tales of the Mabinogi to the contemporary walkers of the Snowdonia Slate Trail. 

The first application in the 1990s was eventually abandoned. Then last year a coalition of concerned NGOs including Save Our Rivers and the Snowdonia Society successfully objected to a new proposal. This latest developer has now returned with a revised application, which although less visually intrusive has even greater ecological concerns.

Small scale hydroschemes produce insignificantly small amounts of power for disproportional environmental and landscape impact. This schemes maximum installed capacity is 600kw (60 people taking a shower) around 1/13th of a modern offshore wind turbine, such as those sited within view of the North Wales Coast.

In fact the last 90 hydroschemes permitted by Snowdonia National Park Authority, all added together contribute less to power production than 1 single large offshore windturbine. See more about our concerns for small scale hydro here.
Schemes such as this also lead to fragmentation of a free-flowing river. Only 1% of all rivers in the UK are currently free from artificial barriers and, thanks to the recent spate of hydro development in Snowdonia, few remain free flowing within the National Park.

The impact of the pipeline on both the landscape and the ecology of the area. The pipeline construction involves cutting a 3.6m working corridor across a river side bog, across a steep hill side under the Slate Trail footpath and through the bed of the Afon Cynfal itself. Other impacts of the pipeline include a 4m by 3.6m cutting through the bed rock of a hill and 3 separate construction compounds.

Save Our Rivers has real concerns around the possibility of a pollution incident damaging to the Afon Cynfal SSSI just downstream of the development. Either sediment from the trenching of the pipeline, or from oil/diesel from the heavy machinery fording the river.