The lake is now part of the
Waitaki hydroelectric scheme. The lake's original outflow was at its southern end, into the
Pukaki River. The outflow has been dammed, and canals carry water from Lake Pukaki and
Lake Ōhau through the
Ōhau A power station to
Lake Ruataniwha. Pukaki is also fed by the waters of
Lake Tekapo, which are diverted through a canal to a power station on Pukaki's eastern shore (Tekapo B station). The lake has been raised twice to increase storage capacity (by in 1952, and in 1976), submerging Five Pound Note Island, which once appeared on New Zealand's five pound note. The current lake has an operating range of (the level within which it can be artificially raised or lowered), giving it an energy storage capacity of 1,595 GWh. Along with Lake Tekapo's 770 GWh storage, it provides over half New Zealand's
hydroelectricity storage capacity. In September 2012,
Environment Canterbury approved a change in conditions of
Meridian Energy's
resource consent controlling the water levels and flows of Lake Pukaki. The change allows Meridian to lower the lake a further from the minimum level of above sea level in the event of an energy crisis. File:Lake pukaki 27.jpg|Lake Pukaki, looking towards Mount Cook, in summer File:Tahr 27.jpg|Statue of the Himalayan Tahr, introduced to New Zealand in 1904 File:Lake Pukaki Tahr sculpture 287.JPG|Plaque providing details about the introduction of the tahr File:Lake Pukaki with Aorangi in the distance, as seen in November 2015.jpg|Aerial view of Lake Pukaki (2015) ==Nearby settlements==