Dam it, we need a decision
THE debate over whether to raise the wall of Tweed's Clarrie Hall Dam is back on the agenda after Tweed Shire Council officers warned a decision must be made on upgrading the spillway to avoid a disaster in an "extreme flood."
Councillors voted in October not to raise the wall of the dam south west of Murwillumbah and not to build another dam at Byrrill Creek, further west, with any decision likely to be left to the next council after the election in September next year.
But council officers want them to vote next week on a $6.3 million upgrade to the spillway of the Clarrie Hall dam warning "the do nothing option presents an unacceptable risk to the people and property located downstream."
The move raises the prospect of the council voting to upgrade the spillway with a future council later deciding to raise the wall.
However this morning prior to opening a new bridge near the shire's western boundary mayor Barry Longland said he was confident actual construction work would not begin before a new council was able to reconsider raising the wall and preparations for the spillway could be "integrated into that."
He called for "common sense" over the dam issue, saying rasing the wall of the Clarrie Hall Dam - which has been fiercely opposed by affected farmers - was the best option for Tweed's future water supply.
Cr Longland said an upgrade of the spillway was a requirement of the Dams Safety Committee of NSW, which reviewed all dams in the state in the light of new standards relating to "probable maximum floods."
"To integrate the spillway upgrade with the rasing of the dam wall was going to be the most cost efficient option," Cr Longland said.
"It's unfortunate that was overturned. We don't have an option not to proceed with the spillway upgrade.
"The new standards meant a lot of these spillways weren't up to standard. They (the Dams Safety Committee of NSW) originally gave us to 2014 to complete the spillway upgrade but that was extended to 2017 to allow for the water supply augmentation.
"I'm hoping commonsense will come into this debate.
"Our future water security would be more than adequately met through raising of the Clarrie Hall Dam."
Cr Longland said that option "has the least environmental consequences" would be the least costly and "land resolutions would cause the minimal upset".
He hoped councillors would vote to proceed with the spillway upgrade but believed "it will take years before there's any kind of earthworks."
He said that would provide time for the next council to decide to raise the wall as well.
Council staff say it is "envisaged that the proposed works will take six months to complete, with works expected to start in early 2013."
They also warn the water level of the dam "may be dropped for a period of time to enable works to be undertaken."