LESLIE Harrison Dam’s gates will not be refitted, quashing residents’ hopes that the dam will operate again at full level.
Seqwater lowered the dam’s water and removed the gates – originally fitted by Redland taxpayers in 1984 – in 2015 as part of engineering investigations and to improve safety.
The quango announced yesterday the gates would not go back on given most of Redland drinking water is sourced from North Stradbroke Island and the district also is now part of the SEQ Water Grid.
Once the upgrade was complete, the dam would remain at its current level, disappointing surrounding residents who enjoyed more expansive lake views when the dam operated at a higher level.
Seqwater chief executive Jim Pruss said modelling showed the additional water that the refitting of the gates would supply was not needed and that the lowered dam level would not affect water security.
“To reinstate the gates would require additional upgrade work that would need at least a further $18 million investment to a total of $42 million,” Mr Pruss said.
Cr Paul Gleeson attacked the decision, saying it was a terrible outcome.
“Not only did the state government take the dam from Redland City ratepayers, it’s now clear that they don’t want to maintain it,” Cr Gleeson said.
“By reducing the holding capacity, they’ve devalued what was a fantastic council-owned, income-producing asset.”
Mr Pruss said Seqwater was not able to justify the additional investment, which would have been added to the cost of drinking water.
A total of $24 million would be spent on a wall upgrade but the dam would not be opened up for recreation as some groups had sought.
Cr Gleeson said the government’s revenue from the bulk water supply had jumped 65 per cent from 2012-13 to 2016-17.
“In the last five years, the state government has received almost $130 million dollars in bulk water charges from Redland ratepayers so a full upgrade and reinstatement of the dam gates should be a priority,” he said.
Mr Pruss said the upgrade would see the main embankment and spillway strengthened to withstand more extreme weather events.
The upgraded dam would continue to provide flood mitigation.
“There is no loss in the level of flood mitigation provided by Leslie Harrison Dam as a result of the spillway gates being removed,” Mr Pruss said. “.. Gates were added for water supply and not to improve flood mitigation.”
The upgrade will take about two years to complete and will start next year.
The dam was built in 1968 and has not received a major upgrade since its spillway gates were installed in 1984.