Murray Darling Basin salt interception schemes damaged

Most of the Murray Darling Basin’s salt interception schemes that were damaged in the 2022 floods have not been repaired, putting communities’ water quality at risk.

Salt interception schemes that are vital to protecting the Murray Darling Basin and its communities are yet to be repaired in the wake of the 2022 floods.

Most of the Murray Darling Basin’s 12 salt interception schemes that were damaged in the 2022 floods have not been repaired, putting at risk irrigation communities’ water quality.

The independent audit group’s latest salinity report found Victoria’s Pyramid Creek scheme met its operational targets just 29 per cent of time in 2022-23, Mallee Cliffs just 25 per cent, Mildura-Merbein 7 per cent and South Australia’s Loxton and Pike River schemes 8 per cent.

The Murray Darling Basin’s salt interception schemes’ performance has crashed.

The audit group said they were “briefed by the MDB Authority that the last two years have been very challenging for the operation of the SIS (schemes), largely due to the 2022-23 River Murray flood event that required some of the SIS to be shut down and caused significant lasting damage to some of the schemes.”

“The IAG was advised some of the schemes or parts of schemes are operational but substantial funding will be required to reinstate full operational functionality.”

Just how much funding has been made available remains unclear, with an MDBA spokesman stating it had “enacted Clause 56 (Water Act 2007) allowing state constructing authorities to progress repair works on a priority basis”.

“Final figures are not currently available as major repairs are still in progress.”

Works include reinstating and repairing bores and pumps, along with their electrical switchboards and power supplies, rebuilding access tracks and site cleanup.

The MDBA said temporary measures had been implemented “to resume minimum operations of the schemes while formal infrastructure repairs commenced at the earliest feasible opportunity”.

The audit group concluded: “There is considerable uncertainty about the long term implications of the 2022 floods for land salinisation and the risks to the shared water resources”.

Water tables have already risen in response to the floods across the the Loddon Valley and Shepparton irrigation districts.

“There is no doubt that there are large increases in salinity risks when there are consecutive years with above average rainfall,” the group reported.

“The past two years have highlighted the dynamic and episodic characteristics of salinity in the landscape that require ongoing management.”