The A$70 million upgrade is expected to be completed during 2013 and Stage One involves the construction of a four-bay, 250-metre (820 ft)-wide, fuse plug spillway at Diamond Bay to enable the dam to safely pass extreme floods.

[7] Unexpected erosion of hard, sound, unweathered granite in the unlined spillway discharge channel was caused by rock failure under high in-situ compressive stress.

A concrete slab, anchored to the underlying rock was constructed in the floor of the main scour channel to provide some additional protection on those rare occasions when the secondary spillway will discharge water over this area.

[8][9] A hydro-electric power station generates up to 21 megawatts (28,000 hp) of electricity from the flow of the water leaving Copeton Dam with an average annual output of 54.3 gigawatt-hours (195 TJ).

[10] Copeton Dam offers sailing, windsurfing, boating, water skiing, fishing and swimming while bushwalkers can enjoy unusual geological formations, lake and mountain views and a wide variety of plant life.