Following extreme temperatures and two of Australia's driest years on record, water storage levels across the ACT dropped below 45 per cent last summer, causing Icon Water to warn against impending water restrictions this time last year.
A wetter than average winter and La Nina's arrival in spring has meant storage has recovered significantly, with overall levels now at 98.26 per cent.
While supplies look healthy, Icon Water has warned against complacency as the provider anticipates future drought.
Customer engagement manager Davina McCormick said Icon expected changed weather in Canberra.
"Australia is the second driest continent on Earth, and we cannot rule out significant drought again in our future," Ms McCormick said.
"Based on current climate science advice, we expect that in the long term, weather conditions in the Canberra region could become hotter and potentially drier.
"This will impact water availability and increased demand may result in additional stress on the ACT water supply."
Ms McCormick said it didn't mean Canberrans should anticipate water-supply shortages, having avoided restrictions during Australia's worst drought.
"Canberra's long-term water future is considered to be secure following major investments in source water infrastructure coupled with reductions in demand following the Millennium Drought," Ms McCormick said.
Prior to the drought, the ACT's annual consumption was around 70 gallons.
Since 2000, Canberrans have maintained a 35-40 per cent reduction in water use, with annual consumption around 50GL despite the growth in population.
McCormick said conservation measures such as only using a sprinkler in the cooler parts of the day, the use of water-efficient appliances in new dwellings, population density creating smaller blocks with smaller gardens and the increased cost of water, all contributed to the drop in water use.
She said behavioural change had the biggest impact.
"When water restrictions were introduced during the Millennium Drought, the reductions in water usage achieved by the Canberra community prevented us from running out of water," Ms McCormick said.
"Water usage has only increased marginally since restrictions were removed - indicating a permanent shift in behaviour."