SH1 reopens with warning river has little flood defence
State Highway 1 across the floodravaged Rangitata River reopened last night after being closed to traffic since last Saturday morning.
NZ Transport Agency system manager Pete Connors urged caution from motorists, saying there will be temporary speed limits in some places.
‘‘The Transport Agency thanks everyone who has been working and continues to work on these repairs and on the detour route via Arundel since the weekend for their long days and dedication.’’
The bridge was closed when floodwaters from the Rangitata River spilled across the highway and bridge approaches.
The alternate road over the Upper Rangitata Bridge at Arundel was also damaged and flooded but was reopened on Monday for the thousands of travellers stranded in South and Mid-Canterbury.
‘‘People can expect to see work continuing to strengthen the bunds around the river and stopbanks right through to Christmas,’’ Connors said.
After peaking at 2200 cubic metres of water a second (cumecs) during the Saturday flood, the river has now dropped to 330 cumecs – still five times its average flow.
‘‘Given the pounding taken by the river’s protection systems at the weekend, it remains vulnerable in any future flood events,’’ warned Environment Canterbury.
‘‘We expect the river flows to continue to slowly drop over the next two days, and the weather forecast over this period is looking good.
‘‘Significant flows are still going down the south branch.
‘‘The river system is in a very sensitive state and even with these lower flows, changes in flow patterns are possible, which could result in overland flow paths changing.’’
All residents in the area had been advised to be wary of these possible changes.
ECan said eight heavy machines were working at various locations in the river to return flows to the main channel.
‘‘Every effort is being made to stop outflows and we anticipate significant improvement in the situation over the next two days.
‘‘It is important to note that the works being carried out this week are to relieve ongoing flood outflows.
‘‘While improvements will slowly occur, works to restore flood protection will take much longer (weeks to months) and the river remains highly vulnerable to any future weather events.
‘‘We continue to urge landowners in the area to use extreme caution and ensure your own safety as the situation could change throughout the day,’’ ECan said.
Timaru Civil Defence emergency operations public information manager Stephen Doran said they were ‘‘beginning to transition from the response to the recovery period’’.
‘‘We’ve had staff from Waimate, Mackenzie and Selwyn assisting; it’s been all hands on deck.
‘‘We’ve also had teams from Civil Defence and the NZ Transport Agency assisting.
‘‘Everything is starting to calm down a bit.’’
Doran said the Rangitata River was still flowing through the south branch.
‘‘While those river levels drop it might do something.
‘‘We are hoping the evacuation status will change to a flood risk zone today. People will be able to enter the area but they have to be aware of the risks and not take any chances.’’
Doran said there was still likely to be water on the roads and in paddocks.
‘‘We have response and welfare teams who are checking on houses.
‘‘The farmers will be really stressed out at the moment. Farm infrastructure damage is high through out the area.
‘‘The key thing is moving from response (keeping people safe) to recovery (taking stock of what the damage is), and helping local residents recover.
‘‘What we have to focus on is rural communities that have suffered serious loss.
‘‘It is a very dynamic situation and there is very little flood defence.’’