The Otago Regional Council believes the collapsible floodgates at the head of the Lower Clutha floodway should be removed.
During the floods of 1995 and 1999, issues with the operation of the gates compromised the effectiveness of the floodway, a report to the Otago Regional Council's engineering and hazards committee said.
The floodway, which directs floodwater into the Koau branch of the Clutha River, is owned by the regional council and leased out for grazing.
Environmental engineering and natural hazards director Gavin Palmer said there were few events in which the gates could be used, and removing them would benefit the wider community.
"They do not serve a useful purpose and the staff feel they ought to be removed."
The staff report said the floodway was controlled by 69 steel flashboard gates along the entire crest of a 331m-long weir.
"The presence of the gates creates an impression that a higher standard of flood protection is provided to the floodway than is actually achieved," the report said.
During high flow conditions, the gates, which were operated by a series of wire ropes connected to a winch, were dropped, the report said.
However, in 1995 many of the gates did not drop and the flow of floodwaters split between the Koau and Matau branches, placing more pressure on the Matau floodbanks.
It was best to drop the gates just before the water entered the floodway, the staff report said.
"In practical terms this means removing the gates, as they would serve no real purpose," it said.
Removing the gates would increase the "operational robustness" of the scheme and the safety and efficiency of staff, the report said.
The proposal had been discussed with the council's lessee, who was concerned at the impact on his farming operation.
Cr Stephen Woodhead said the report would be presented to the Lower Clutha scheme liaison group in October.
If it was accepted it would be returned to the committee for final approval.
