Earthquake repairs to roads and underground pipes in Christchurch could take up to a year longer than planned to complete.
Repairs were supposed to be completed by the end of this year.
Christchurch City Council infrastructure committee chair Phil Clearwater said today completion may not be until the end of 2017 due to the complexity of the work.
"Overall, most of the time, Christchurch people understand that in fact this isn't easy ... a lot of frustration for everyone whether people are walking or biking or taking their cars home, that there are so many roadworks on all at once."
He said the repairs were likely to cost the council $150 million more than it initially budgeted, partly due to the government scaling back its funding of the work.