Cut in Waiau River bar to be tested
The effectiveness of a cut made to open the Waiau River bar and hopefully delay further erosion of the coastline will be tested this weekend, with rain and heavier flows through the river expected.
Environment Southland’s contractors completed the cut on Thursday to realign the river opening to the sea in the hope of making it safer for 18 houses and cribs at Bluecliffs near the river mouth.
A state of emergency has been in place at Bluecliffs since the beginning of the month after three metres of land fell into the sea.
“It looks like there will be rain in Fiordland this weekend which will provide a dose of water down the Waiau River,” Southland Civil Defence emergency management group controller Simon Mapp said.
“We are currently awaiting the weekend's increased river flow and incoming weather to determine the effectiveness of the bar opening.“
He said as contractors worked on opening the 10 metres high, 30m wide bar, Meridian Energy had managed the flow release at the Manapouri Lake Control making it safer.
This weekend there would be a gradual increase in the release of water from the control gates.
He warned anyone planning to be near, or on the river, to take care.
“The area around the new opening is extremely dangerous.
“Some access points around the area are still restricted.”
Opening the bar would, he hoped, reduce erosion in front of the Bluecliffs houses and cribs, as well as the tip.
“But it’s unknown if the bar will take 100% load or slowly migrate as it has done in the past.”
During the past two weeks, 30,000 cubic metres of mostly gravel were redistributed around the bar.
Mapp said Bluecliffs residents were being allowed to stay in their homes at present, with emergency housing in place at Tuatapere just in case.
Removing material from the Bluecliffs tip site was expected to start in the next few weeks, he said.
Attempts were still being made to find an explosives expert to follow up a claim from an anonymous source that that there could be explosives in the tip.