Chris Dobney
The Belongil now has a floodplain management plan after years of consultants’ work and despite the concerns of residents and some councillors that the plan might be seriously flawed.
Shirley Lane residents Cath Walton and Jay Pearson told public access they worried that the adjacent Cumbebin Swamp, together with their local Belongil Creek tributary, would be ruined if a proposed massive pumping station was built nearby.
And Belongil resident Laurie Lynch told council he did not believe the consultant’s report was backed up by proper data. Mr Lynch even went so far as to conduct his own measurement of flows in Belong Creek during a flood, which he claimed showed the consultants’ modelling was ‘out of whack’.
Ms Walton said, ‘the creek is tidal and more prone to flooding when the creek mouth is not opened’.
She added the area, which was ‘abundant in wildlife’, was maintained by local residents.
‘We don’t want pumps, drains and levees installed. We’re concerned that in future development will take over last refuges of nature left in the Bay,’ Ms Walton said.
Pumping station
Ms Pearson said the area had been identified as a prime opportunity for water-sensitive urban design in the future, which was in line with proposals of the Byron Bay draft masterplan.
‘Infrastructure needs to deliver solutions for local residents as well as council. The proposed pumping station will be ugly, destroy amenity of the wetland and the shared pathway,’ she said.
Ms Pearson added that local residents did not receive a letter advising them of council’s intentions.
Computer modelling
Mr Lynch said his measurements of the velocity of Belongil Creek, conducted after a 200mm rain event with a high coastal surge and two-metre tide showed surface flows of 0.3metres/second over 10-metre and 20-metre distances two hours after high tide
This compared with consultants’ modelling of up to 4 metres/second for a one-in-100-year event, he said.
But under questioning from Cr Di Woods, infrastructure manager Phil Holloway said data was available from the consultants, though not it was contained in report.
‘Computer models large and complex and can take up to 24hrs to run,’ he said.
‘I’m happy to talk to council regarding its needs for data for reports in future,’ he added.
Masterplan
Mr Holloway also told the meeting that the specific proposals, such as pumping stations and levees need not necessarily be implemented ‘if the same outcomes can be obtained by other methods that are more in line with the masterplan’.
Several councillors questioned whether the masterplan’s authors had been party to the floodplain management plan, particularly as many of the former’s recommendations had to do with water sensitive design and stormwater harvesting methods, such as building an artificial lagoon behind Clarkes Beach.
Mr Holloway said the masterplan consultants had been provided with copies of the floodplain management plan, along with numerous other council studies, but had not commented on it as yet.
The mayor asked if there was value in holding back the report until the masterplan was finalised ‘so we can have integrity in the process’.
Mr Holloway responded that more than five years’ work had so-far gone into the plan and that opportunities to apply for grants to implement some of its recommendations would be missed if approval of the plan was deferred.
Greens councillor Duncan Dey urged council to approve the plan, despite its apparent shortcomings, so that council could ‘move on’.
He added that since a house that had been earmarked for demolition after being declared as being in a flood zone had since been rezoned as safe, he had no further reason to delay approval of the plan.
Cr Dey, who is himself a flood hydrology specialist, said his ‘biggest regret with design of this plan is a couple of humungous pumps built in town to lift stormwater. That’s nearly the worst thing you can do’.
But he said, ‘the process is taking so long, my inclination is to get it out, pay off the consultant and do a review. It will incur costs but it just needs to be sealed off and hearing that there will be options to review it makes me feel we should just get on with it.
‘The first thing you get in a one-in-a-hundred-year event is a blackout and those pumps won’t be working,’ he added.
The motion to adopt the management plan was passed unanimously.