Further repairs can be carried out on the “critical” Clyde Tidal Weir in Glasgow after councillors approved the use of an extra £725,000.
A bolt failure on the weir’s north gate in 2017 allowed water to escape, leading to the collapse of riverbanks.
Work to fix the fault has so far cost £2m, but more defects have been identified.
Another £3m is expected to be required to cover future repairs to the middle and south gate.
Councillor Anna Richardson, city convener for sustainability and carbon reduction, said the weir was a “critical piece of infrastructure within the city”.
The weir maintains the upstream river at a constant level, maintaining bank stability, and is situated near the western end of Glasgow Green.
Three gates are raised or lowered depending on the tide and river conditions.
Council director George Gillespie said the £725,000 would come from existing capital budgets.
More in-depth investigations, which were possible once a dam had been constructed to start the repairs, found “several defects”, a council report stated.
These include damage to the face plate and guide rails, which allow the gate to be raised and lowered.
The two remaining gates can still be used but need “significant refurbishment”. Both the middle and south gate have experienced “significant wear and tear”.
Labour councillor Eva Murray asked for a timescale for these repairs.
A council officer said they were waiting on a specialist report on the damage to the existing gate, which would allow them to assess what work the other two gates required.
Green councillor Martha Wardrop suggested submitting a bid for the required £3m to the UK Government’s levelling up fund.
She said: “The tidal weir gets forgotten when officers are discussing projects.
“It’s been forgotten for many years and it’s unique to the city and we need to invest in it.”
Council leader Susan Aitken said deadlines for the first round of levelling up funding were “incredibly tight”.
“If we were able to construct the wider case for funding for the tidal weir then I think we could look at it for future rounds,” she added.
Cllr Richardson agreed to amend the agreement to state all funding options would be explored to secure money for the south and middle gates, including the levelling up fund.
By local democracy reporter Drew Sandelands