New cycleways connecting Wellington's eastern suburbs to the city have blown their budgets to the tune of $12 million.
The cost escalation on Cobham Drive and at Evans Bay raises wider questions about Wellington City Council's budgeting processes.
Budget blowout after budget blowout has landed on the council's table recently, whether it's earthquake strengthening, transport projects, or water infrastructure.
A new two-way bike path and separate footpath are being built along the seaward side of Cobham Drive.
It's the main transport route to and from Wellington Airport and is often the first glimpse of the city and its harbour for visitors.
But the council has had to reprioritise money from other unspent project budgets to cover the $6.7 million overspend at Cobham Drive.
The cost escalation is due to rock revetment work, to prevent coastal erosion, and unexpected costs associated with varying ground conditions.
The extra money had already been spent on the project by the time the issue got before city councillors, so they really had no choice but to sign off on it.
A similar path is being built around Evans Bay, from Carlton Gore Rd on Oriental Bay to Cobham Drive.
It's hoped that once the project is complete, that scenic part of the coast will be even more of a drawcard for visitors and recreation.
But councillors have had to bring forward additional money into this year to cover the $5.4 million shortfall so work can proceed.
That cost escalation is due to ground conditions, the addition of a balustrade, and the discovery of old pipes, which had to be removed.
Deputy mayor and cycling portfolio leader Sarah Free said both were projects to be thoroughly proud of, even though they have come in at a higher cost.
"In some ways this shouldn't be a cost attributed to cycleway and walking projects, it probably should have been costs attributed to seawalls and resilience", she told her colleagues at a recent Strategy and Policy Committee meeting.
"But we actually don't have those budgets, we only have $8 million in our seawall budget and that's clearly not going to be adequate going forward into the future.
"So these have had to be accommodated within the cycleway budget. If we hadn't have done this work now, we'd have been looking at a possible undermining of the work and having to go back and fix it", Free said.
Mayor Andy Foster agreed they were excellent projects and was impressed at the level of detail involved - like built-up steps at Point Jerningham to dissauade penguins from hopping up near the road.
But he said when the council went through this kind of process again, its budgeting processes have to be improved.
"Sometimes we put a number in a budget at a certain point in time, which says we think the cost is a million dollars and then 10 years later it turns out it's two or three. We've got to do better than that."
Foster said he liked the way plans to remediate or rebuild Wellington's closed central library have been budgeted using cost brackets.
"I think that's a much smarter way because we inevitably end up getting beaten up for missing a target, which we were never going to hit in the first place."
The mayor issued a plea to the council's chief executive Barbara McKerrow.
He asked that when council officers became aware of a likely significant overspend, they came to councillors then and there formally.
"Rather than at the point where we cannot do anything about it", he said at the committee meeting.