According to Wikipedia, the deepest lake in New Zealand is Lake Hauroko in Fiordland National Park at the south end of the South Island, 463 meters deep (1,519 feet).
Lake Grassmere
Lake Taupo in the North Island
Lake Rotorangi
Lake Taupo, in the middle of the north island.
Lake Willoughby, VT
Lake Hauroko which is 462 meters. The deepest lakes are the group of lakes in Fiordland, which have been sculpted by glacial action. In Wikipedia there is a list of lakes in New Zealand, and a sub-section listing the deepest.
wastwater
Lake Ontario at 802 ft.
I believe it is Seneca Lake
Lake Hauroko, situated in Fiordland in the southwest of the South Island, is New Zealand's deepest lake with a depth of 462 metres.
I don't know the answer, but I'd think Lake Te Anau would be in the top three, with its large fiord-like arms.
The average elevation for Queenstown New Zealand is 520m but the town centre is beside Lake Wakatipu which sits at 310m, it's New Zealands longest lake and is also the 3rd largest, at its deepest point it reaches 10m below sea level, that's a total of 420m deep.