Irrigators, power companies and mountaineers could all be affected if climate change leads to changes in snow levels.
New research from the National Institute of Water and Atmospheric Research (Niwa) revealed that snow melting off the Southern Alps has a greater impact on North Otago waterways more than anywhere else in the South Island.
An assessment of 20 years of daily temperature and precipitation data from the Virtual Climate Station, showed that of the large rivers that reach the sea, the Waitaki had the highest snowmelt contribution with 12 per cent, while Lake Pukaki had the highest snow-melt inflow of any South Island hydro lake with 18 per cent.
Niwa hydrology scientist Dr Tim Kerr said the findings would have important consequences for people involved in water management, and civil defence.
"Increased flow from snowmelt in summer is beneficial for irrigation, but decreased flow in winter, when snow builds up, is problematic for hydro-electricity."