Weir construction project delayed but structurally sound following record rainfall
The construction of the Rock Ramp and Fishway at the South Dubbo Weir has been significantly delayed because of record rainfall in June and high river flows meaning construction is not likely to recommence for some weeks.
Western Plains Regional Council Director Technical Services Stewart McLeod said despite the delay in construction structurally the work completed to date is sound and it is clear that the design is functioning as intended.
“The high rainfall came towards the end of the first construction stage so approximately one half of the Rock Ramp and Fishway has been constructed,” Mr McLeod said. “The high water flow inundated the work area and with continued high water flows it is not possible to recommence construction,” Mr McLeod said.
“Council is also required to remediate the right hand bank where a significant washout has occurred as a matter of priority,” Mr McLeod said. “The washout occurred as the increased flow of water over the weir created a circular current or eddy which eroded the river bank from the water level creating an undercut which then caused a significant part of the bank to slip,” Mr McLeod said.
“Access to this part of the river to start the remediation has been hampered by the high water flows and for public safety the section of the Tracker Riley Cycleway that passes the weir will be closed for the foreseeable future,” he said.
Council is working with construction supervisors NSW Public Works, contractors David Payne Construction and the Department of Primary Industries to assess the plans for remediation and the impact on the Rock Ramp and Fishway construction to ensure work can commence as soon as practicable.
Mr McLeod said the delay in construction was not unexpected considering the variable nature of the weather and the inherent challenges of working in the river.
“While the project has been delayed it is clear that the design of the Rock Ramp and Fishway is achieving the desired result and once construction can recommence a timeframe can be set for its completion,” Mr McLeod said.
Council’s Director of Technical Services
(02) 6801 4000
Last Edited: 25 Jul 2016