Council kills anti-chlorine
“The rationale for the decision appears to be based on costs, but those cost calculations don’t appear to be entirely rational.”
Council estimates preparing for a chlorine-free trial, including thoroughly flushing the mains and sealing the 10ML reservoir at the Mossman treatment plant, would cost at least $2.75 million.
This is more than three times the cost estimate by council’s consultant Black & Veatch, which thought preparatory work for the trail would cost around $820,000.
The council estimate includes $1.7 million of works which critics say should be part of a maintenance program, such as flushing the pipe network, replacing two-thirds of the fire hydrants in Mossman and replacing or repairing the reservoir roof.
Former mayor of the Douglas Shire Mike Berwick challenged council to provide revenue data for the water supply network. He said many of the works proposed by council “should be done anyway or are unnecessary”.
“For example, re-roofing the reservoirs should have happened long ago, as soon as they discovered rats and birds could get into them,” Mr Berwick said.
“When a private person installs a water tank, they are required by law to make them mosquito proof (because of dengue and the like) let alone rat-proof.
“Another example is flushing and/or scouring the mains to remove sediment.
“If there is sediment in the pipes they should be flushed regardless of whether chlorine is used or not.”
Australia’s top water scientist Professor Don Bursill agrees.
“If the system is so loaded up with crap, it needs to be cleaned out effectively whether or not the system is to be run without chlorine,” Prof Bursill said.
Prof Bursill also rejected the suggestion the Mossman treatment plant needed further upgrading to deal with the raw water.
“It would be highly unlikely that the source water would contain sufficient levels of DOC to be a show stopper for a chlorine free system,” he said.
Mr Gardiner said sealing the reservoirs and high-pressure flushing of the mains would improve the chances for success of the trial, but would not be necessary if the system remained chlorinated.
“A lot of these works would need to be done (with or without chlorine),” Mr Gardiner said.
“The reservoir roof, we think it’s pretty solid for a chlorinated system.”
Mr Gardiner said council would not replace the reservoir roof if the chlorine-free trial did not go ahead.
Division 10 councillor Julia Leu said she was very disappointed and frustrated that council had decided not to proceed with the trial following four consultancy reports over the past two years.
“I think Mike Berwick raises some valid points, and council should have sought answers to those before making a final decision,” she said.
“Residents of Douglas are expected to pay for multi-million dollar projects in other parts of the Cairns region.
“I think residents are outraged that reservoirs are still vulnerable to contamination. We’ve spent nearly two years to get here, and we’ve finally got a way forward, a road map to de-chlorination.
“I’m not prepared to accept this is the end of the road.”