Eglwys Nunydd

Eglwys Nunydd covers 260 acres (110 ha),[4] has a shore line two thirds of which is in the form of a concrete bowl.[3] and is around 14 feet (4.3 m) deep.[2]

Eglwys Nunydd has shallow, alkaline water with a bed that comprises mainly silt and cobbles where the fertility encourages weed growth which in turn promotes a productive insect population.[4] It was originally designated as a Site of Special Scientific Interest for its birdlife in 1972, and this was confirmed in 1982. The site is notable for its breeding birds which include great crested grebe, little grebe, mallard, gadwall and Eurasian coot.[5] Other species normally present include tufted duck and common pochard and among the local birdwatchers it has a reputation for producing locally rare birds such as goosander, smew, long-tailed duck, greater scaup and great northern diver.[6]

In 2010 it was reported that the invasive amphipod Dikerogammarus villosus had been found in the reservoir.[7] However anglers have observed that these crustaceans form a major part of the diet of the reservoir's stocked rainbow trout and have been told to be aware of biosecurity when fishing so they do not transfer the "killer shrimp" to other waters.[4]

The lake supports a trout[1] and coarse fishery managed by Tata Game Angling.[3] and is used for dinghy sailing run by the Tata Sailing Club.[2]