The Snowy Scheme was designed to cope with large variability in inflows. In the last 110 years of data, inflows have ranged from 683 gigalitres (GL) seen in 2006/07 during the worst drought on record, to 5761GL almost a century ago in 1917. The long term average is just below 2800GL.
The total volume in Snowy Scheme storages is massive and it would take a number of consecutive years of above average inflows to return our total storage volumes, particularly Lake Eucumbene, to above average levels.
We can expect to receive around 50% of our inflows from snowmelt and rain during spring, so a bad snow season can have a significant impact on the total inflows for the year.
2015-16 WATER YEAR
What inflows came in?
Snowy Scheme inflows for 2015-16 were 1650GL which is about 60% of the long term average of 2771GL.
We would need multiple years of average or above average inflows to see major sustained improvements in lake levels. In 2015-16 we received below average inflows, therefore further increasing the time it will take for storages to return to long-term average levels.