Afon Clun - Ecology

Ecology

Average annual rainfall in the area is 73.9 inches (1,880 mm).

Bedrock along the river's course is predominantly sandstone.

The Clun's water quality is generally class RE2 or better.

[Note: River Ecosystem Classification (RE) regulations and EU Directives for Bathing Water, Freshwater Fisheries, Dangerous Substances and Urban Waste Water Treatment;

RE1: 'Water of very good quality suitable for all fish species';

RE2: 'Water of good quality suitable for all fish species';

RE3: 'Water of fair quality suitable for high class coarse fish populations';

RE4: 'Water of fair quality suitable for coarse fish populations';

RE5: 'Water of poor quality which is likely to limit coarse fish populations.']

Afon Clun and its tributaries are designated 'salmonid waters and cyprinid waters' by the Department for Environment, Food and Rural Affairs (Defra) under the EC Freshwater Fish Directive (2006/44/EC), which sets physical and chemical water quality objectives to protect fresh water bodies suitable for sustaining fish populations

Rhondda Cynon Taf (RCT) has designated the Afon Clun Valley and Rhiwsaeson Hill as a Site of Important Nature Conservation, which is intended to provide the area with some protection from development. In addition, RCT has designated the undeveloped areas of the southern bank of Afon Clun (from Rhiwsaeson to Coed-yr-Hendy, including Mwyndy) and Efail Isaf, Garth and Nantgarw Western Slopes as Special Landscape Areas (SLAs). (SLAs) are intended to protect the visual qualities of "areas of fine landscape quality", when considering development proposals. Coed-yr-Hendy and Mwyndy consist mainly of "undisturbed" fields and woodlands. The south and west of the Efail Isaf, Garth and Nantgarw Western Slopes area consists of farmland – considered to be a buffer between The Garth and the urban area of Efail Isaf and Church Village. The eastern part is the prominent wooded slopes of the Taf Valley – a backdrop to the Treforest Industrial Estate. SLAs are identified using the Countryside Council for Wales' LANDMAP criteria, considering factors such as prominence, spectacle (dramatic topography and views), unspoilt areas (pre-industrial patterns of land use), remoteness and tranquility, vulnerability and sensitivity to change, and local rarity of landscape.