SA Water today said its metropolitan reservoirs reached 93 per cent capacity at the start of December – compared to 72 per cent at the same time last year.

More than 80 billion litres of water entered the system over spring, marking the wettest spring since 2002.

SA Water said that on just one day, September 18, seven billion litres entered the catchment.

The ongoing rainfall prompted five metropolitan reservoirs – Mount Bold, Kangaroo Creek, South Para, Myponga and Warren – to open their floodgates over spring.

[solstice_jwplayer mediaid=”CPrutmCs” title=”Water flows out of Kangaroo Creek Reservoir in November” caption=”Video: SA Water” /]

James Crocker, SA Water’s senior manager of wastewater expertise and environment, said it was the first time since 2016 that five South Australian reservoirs have needed to release water.

“A late rainfall rally in August set up prime soil conditions for spring to generate a significant impact on water levels in our reservoirs, growing in leaps and bounds particularly during September, which delivered the year’s largest individual day for inflows to date – seven billion litres during the 24 hours on 18 September,” Crocker said.

“Reservoirs such as Kangaroo Creek and South Para enjoyed rapid increases in their storage levels, leading to natural water releases from their spillways in October and November, respectively.”

[solstice_jwplayer mediaid=”VTEH5IUL” title=”A water release from South Para Reservoir in November.” caption=”Video: SA Water” /]

Crocker said the controlled release of water from Kangaroo Creek dam was the first time a recently-upgraded 50-metre spillway was used.

“Excitingly, we witnessed Kangaroo Creek’s new 50-metre-wide spillway in action for the first time since our major dam safety upgrade, as it safely channelled water out of the reservoir downstream into the River Torrens.

“Unlike these reservoirs, our Mount Bold and Myponga storages have a series of gates atop their dams that are controlled manually to release water and manage water levels in the reservoir.

“We performed several controlled releases from our two gated dams during spring, with the aim of managing inflows from the catchment area by moving water out of the reservoir when we have the capacity to do so, while minimising the impact downstream.

“Once again trumping recent years, inflows from winter and spring combined led to the highest total increase in our reservoir levels, with them now sitting at a healthy position as we move into the warmer months.”

SA Water said the state’s metropolitan reservoirs are currently at 91 per cent capacity.