Flooding in the Ashburton River forced the closure of the SH1 bridge on Sunday, 23 July.
Rising floodwaters have now become an unwanted but familiar sight around the Ashburton River/Hakatere bridge on SH1.
The bridge was damaged during floods in 2021 and forced to close, cutting the South Island in half.
On Sunday night, the river's only SH1 crossing shut again after the river exceeded a one-in-10-year flood level. It reopened Monday morning.
Ashburton Mayor Neil Brown said the area has had 160 to 300mm of rain in the last 24 hours, about a third to a quarter of the region's annual rainfall.
He told Checkpoint while there is no further damage to the bridge, Waka Kotahi closed it Sunday night due to concerns about slash.
"What they were wanting to do was to keep an eye on the slash that was building up against the piles on the bridge and they couldn't do that in the dark.
"The only way they could keep the bridge safe was to close it and then once first light came along, they could monitor it again."
But Brown said what this incident proved was the clear need for a second crossing.
"This was another good wake-up call saying that Ashburton needs that second bridge because last night, the South Island, again, was cut in half."
He said the area had been talking about a second bridge for 10 years.
"We've done a lot of work on it, we've done the business cases on it, we got a costing on it and it's really up to the government now to fund it."
Brown said that their costing priced a second bridge at $113 million - now it was just a question of how much the council, Waka Kotahi and the government would contribute.
"We've visited the Minister of Transport Michael Wood, when he was the minister, and he asked us to do a little bit of work on funding options,
"We've done that work but he's no longer there."
The mayor said the council would be going to new Minister of Transport David Parker to see if it could get some certainty out of the government.