- Category: Water Feature
- Type: Inland Water
- Latitude/Longitude: 51°35'52"N 3°42'34"W
- Eastings/Northings: 281687, 190175
- OS Grid: SS816901
- Mapcode Local: GBR H6.BKNM
- Mapcode Global: VH5H2.N389
Location and coordinates are for the approximate centre of Cwmwernderi Reservoir within this administrative area.
Geographic features and populated places may cross administrative borders.