The Department of Conservation Wakatipu area office tasked four rangers and its engineer from Invercargill to fix the critical structure, which was smashed by a falling snow-laden tree last month.
The repair project was completed in-house within two weeks and did not take until the end of September as first thought.
Visitor assets programme manager Richard Kennett said Doc had been conscious of the high use of the bridge and the need to maintain good access with the busy summer season just around the corner.
"A total of 40% of bridging components, hangers and various cables, had to be replaced, along with most of the decking timber," Mr Kennett said.
"Having the bridge up and running again is great news and means that the Routeburn is now able to be accessed again without fording the river."
Doc Queenstown regional visitor centre supervisor Andrew Evans said walkers everywhere would be pleased they could enjoy the Routeburn again.
Centre staff were fielding up to 10 public inquiries per day about the track during the winter season and the number was rising as walking and weather conditions improved, he said.
"The entry at the Routeburn shelter is now open, meaning walkers can access the left and north branches.
"However, Doc should be consulted on the latest track conditions because hazards are still present, including significant tree falls and fluctuating avalanche conditions.
"We're still not recommending the alpine crossing of the Routeburn from Falls Hut through to Lake Mackenzie."
Construction of a completely new bridge will begin in May at the end of the 2008-09 Great Walks season.
The proposed new bridge will allow for 20 trampers to cross at a time, instead of the current maximum of five.
Mr Kennett said all the other bridges between the road end and Falls Hut had been checked and found undamaged.
"There have been no other reports of any other damage on the track apart from the usual minor winter tree falls from wind and snow."
