In response to the discovery of the defects, the council significantly lowered the permitted weight on the bridge, meaning some truck drivers were carrying greatly reduced loads so they could cross the bridge.
The council subsequently lobbied Waka Kotahi for additional funding to replace the two bridges.
Announced by the council on Friday, Waka Kotahi is set to cover 74 per cent of the $4.6 million replacement cost, with the council picking up the remaining 26 per cent.
Ruapehu mayor Don Cameron said the replacement of both bridges was great news and would be well received by local growers and contractors who had been significantly impacted by the weight restrictions on the existing bridges.
"Council would like to thank Waka Kotahi NZTA for their support of these projects in a period of funding constraint and increased competition from other regional transport demands," Cameron said.
"It highlights their careful consideration and understanding of the impacts that the bridge restrictions have been having on the community and wider economy."
Overall, the council has been granted a total budget of $48.3m for the next three years, including funding towards projects around maintenance, speed management, safety improvements and the nationwide "Road to Zero" campaign.
"While our approved allocation of $48.3m is less than our original $50.3m application, it is a $1.5m improvement to the $46.8m indicative funding allocation released in May, and a significant 24 per cent increase from the previous three-year allocation," Cameron said.
"We feel $48.3m for maintenance and renewal for the next three years is a reflection of Waka Kotahi NZTA's support of government's strategic priorities namely safety, better travel options, improved freight connections and climate change."