Time to rethink use of Wivenhoe’s capacity
Wivenhoe Dam’s true capacity was double that being reported and better management of the storage was needed to limit further waste of taxpayers’ money on grids and desalination, the State Opposition said today.
LNP water spokesman Jeff Seeney said reports that Wivenhoe was over 90 per cent full were misleading because at ‘100 per cent capacity’ the dam was less than half full.
Mr Seeney said a 2005 government report showed using just 2 metres extra of Wivenhoe’s storage would add an extra 228,000 megalitres of water and provide an extra ‘no fail’ yield of 31,000 megalitres a year to SEQ’s water supply – equivalent to the total annual yield from a properly functioning Tugun desal plant.
Built in the late 1970s in response to the 1974 floods that devastated Brisbane, Wivenhoe was constructed to hold not just a large water supply, but also act as a flood buffer to help to manage future flooding in Brisbane.
Wivenhoe’s ‘full storage level’ was 1.15 million megalitres – only 44 per cent of total capacity of 2.6 million megalitres.
Mr Seeney said it was time to review management policy so more of the dam could be used for water storage to reduce chances of another water crisis.
“Obviously the dam needs to maintain the flood buffer for Brisbane and any decision on storing extra water will impact on the effectiveness of the dam’s flood buffer role.
“But we need to determine whether the balance that was struck in the early 1980s remains appropriate for the situation today. Much has changed since 1980 … Brisbane and Queensland generally have experienced long periods of low rainfall which saw the real possibility of Brisbane running out of water.
“Since those original decisions were made in 1980, technology has advanced and we are now able to forecast rainfall events far more accurately. Automatic stream flow monitors and advanced models allow for much better decision making in managing any potential floods.”
Mr Seeney called on the Minister to ensure no water was released from Wivenhoe until a proper review of storage policy was undertaken.
“It would be absurd to release water from Wivenhoe until all options are thoroughly investigated,” Mr Seeney said.
“Labor has seriously mismanaged water for many years, brought Brisbane to the brink of running out of water …and blown billions of dollars in a panic on projects that are hideously expensive and grossly inefficient to run. We need to do a lot better.”