Lake Wanaka Preservation Act (No. 107 of 1973).

The overall aim of this Act, consisting of 11 sections, is to preserve the normal water levels and shoreline of Lake Wanaka and to maintain and improve its water quality, essentially via the regulation of "works" which are defined as dams, weirs, gates, locks, booms, excavations, structures or other works. In particular, the Act aims at preserving the water levels of the lake and its shoreline in their natural state, and preventing the body of water from being impounded, controlled or obstructed by any works except in emergency. The Minister of Conservation may appoint Guardians of the Lake whose functions shall include declaring emergency water levels (i.e. which cause loss or damage to human life, livestock or property by flooding), as well as report and make reccomendations to the Minister on the use of the lake for recreational purposes (sect. 5). The responsible local water board is the Otago Water Board. Harbour works on Lake Wanaka are restricted by section 11.