The project is part of a new three-year New Zealand Transport Agency national land transport programme, released yesterday.
Details of the $12.3 billion 2012-15 programme, described by Transport Minister Gerry Brownlee as the largest "in the country's history", revealed that $17 million will be spent over the next three years replacing the twin bridges with two new structures and improving infrastructure on the State Highway 82/83 route.
New Zealand Transport Authority southern region director Jim Harland said a date had not yet been set to start construction, and the NZTA was "committed" to completing work by the end of 2015.
"It will be constructed in the period 2012-15. A start date will depend on overall cash-flow within the NZTA programme, because we have a whole raft of them across New Zealand.
"Consents are in place, a preferred contactor is on board, and all the design is done. The last step is just the timing."
Ahuriri ward councillor Craig Dawson said confirmation of the funding was "fantastic news" for the local community.
"One of the biggest concerns we had was getting emergency services across the Haka [Hakataramea] valley. If anyone had an accident on a farm we wouldn't be able to get a fire engine or anything like that to them."
Mr Dawson said the existing 132-year-old twin bridges were also a fire risk, and caused problems during heavy rains.
"The problem is that they are very fragile. If you actually look down the line of one of the bridges you see it is quite bent.
"A lot of people have been concerned. Also, it is a major trade route. Tourist buses come up that way.
"It is certainly a vital link from the east coast up here."
