Melbourne’s water storages have declined by 5.1 per cent over summer, a result which is in line with the long-term average for the season.
The decline (93.7 billion litres, in volumetric terms) saw storages fall from 78.4 per cent to 73.3 per cent throughout summer.
The four major catchments that harvest most of the city’s drinking water received an average of 185.6mm, which was just short of the 30-year summer average.
The effects of a dry spring were evident in the low volume of water that flowed from the catchments into the reservoirs (streamflow) as a result of the rainfall. With the sponge-like catchment soils already dry from below-average spring rain much of the summer precipitation was absorbed, preventing it from flowing into reservoirs.
The 37 billion litres of streamflow was just over half of the 30-year average for the period.
Reduced water use helped limit the extent of the summer decline. Melbourne homes, business and industry used an average of 1,229 million litres of water a day, which was 70 million litres of water a day, or 5.5 per cent, lower than the same time last year.
Manager of Water Supply, Michelle Riley, said the summer result was not unexpected, and while storages were in a relatively strong position, they were likely to continue declining throughout autumn.
“We expect dam levels to steadily decline over the next few months before the winter-spring filling season begins,” said Ms Riley.
“The most encouraging aspect of summer was lower water use across the board, despite no water restrictions being in place.
“The reduced consumption not only kept some of our precious water in storage but showed us that the water-saving habits adopted during the most recent drought have become a way of life,” she added.