Eglwys Nunydd

Infobox lake
lake_name = Eglwys Nunydd
image_lake =
caption_lake =
image_bathymetry =
caption_bathymetry =
location = Margam, Wales
coords = coord|51|32|58|N|3|44|22|W|type:waterbody_region:GB|display=inline,title
type = reservoir
inflow =
outflow =
catchment =
basin_countries = United Kingdom
length =
width =
area =
depth =
max-depth =
volume =
residence_time =
shore =
elevation =
islands =
cities = The Eglwys Nunydd is a large reservoir in Margam, South Wales originally constructed to provide water for the large steelworks at Margam and specifically for cooling water for the cold rolling mills at the eastern end of the works. Much of the water for the hot end of the plant is abstracted from the Rivers Afan and the Ffrwdwyllyt as they flow through the dock feeder.

The lake supports a managed trout and coarse fishing fishery and is also used for dinghy sailing.