A West Coast river engineer claims the NZ Transport Agency "kicked up a bit of a ruckus" when the council requested a joint visit to critical flood protection work on State Highway 6.
The NZ Transport Agency - Waka Kotahi (NZTA) has been managing key South Westland river crossings, at the Wanganui and Whataroa bridges, for the past 18 months.
The willingness of NZTA to work with the West Coast Regional Council on the route security of the state highway has been described as "very precious".
The regional council's Infrastructure Governance Committee has been keeping an eye on how NZTA is managing the flood risk.
This week, council's chief river engineer Peter Blackwood said he had asked the agency for a joint visit to the sites to give their perspective and insight, "but NZTA kicked up a bit of a ruckus on that".
"NZTA are very precious about their works … they don't like it when we talk to them about it," Mr Blackwood said.
He said they were concerned the clock was ticking towards August -- the start of the Spring flood season -- when it might be "too late".
NZTA has been approached for comment.
Earlier in the year, the council said it would write to the agency outlining its concerns.
This included the need to ensure the bridges were not left compromised by a delay to flood protection work, and to ensure it fitted with council's own approach to managing the flood risk at both rivers.
In particular, the council was concerned about how work by the agency might undermine or compromise flood protection work downstream, given it manages assets on behalf of the Whataroa and Wanganui special rating districts.
River diversion spurs had been installed by NZTA at the southern Whataroa Bridge approach, with a retrospective consent application to come, an action point before the July 9 meeting said.
Design work for similar work at the Wanganui south bank was underway and council expected a consent application in due course.
Council chief executive Darryl Lew said he was concerned "no one would get the opportunity to submit" if NZTA undertook an emergency consent application process, taking a non-notification approach.
This would leave out locals living in the area adjoining both bridges.
"What we are hearing here is that the rating scheme members would want to have a view on that," Mr Lew said.
Infrastructure chairman Frank Dooley said it was not too late for their input on the Wanganui consent.
But Cr Brett Cummings said he could not fathom NZTA justifying using emergency consent provisions under the Resource Management Act, due to the time since the bridge issues arose.
"I find it a bit hard to believe the NZTA are using emergency ones on the Whataroa Bridge when everyone has known about it for so long."
Cr Cummings said council had to put its special rating district concerns to the forefront given the potential serious impact of their work causing the river to 'kick' to the other side and causing havoc downstream.
"If they (NZTA) are going to do work that sends the river to the other side, who is going to pay?
"We should have full control what goes in the river I feel."
Cr Peter Haddock said the council had "worked hard on NZTA" for route security in recent times, particularly to get work done at the Wanganui and it had been raised again in a South Island regional transport meeting last week.