After more than a year of clean-up and rehabilitation, Associate Canterbury Earthquake Recovery Minister Nicky Wagner says the Avon River is now flourishing.
Wagner said work was complete on the river and the river was healthy again.
"The in-river works, which finished this week, mean fish are flourishing, water is flowing faster and the riverbed is cleaner," Ms Wagner said.
"The work has also had an immediate tourism benefit, as deepening the riverbed in some areas has allowed Christchurch's iconic punts to extend their river route and travel upstream even at low water levels during summer.
The work to improve the health of the waterway since the Canterbury Earthquakes has been major and almost 10,000 tonnes of liquefaction sand and silt had to be removed.
"Crews also cleaned 15,000 square metres of gravel beds, rescued more than 1,500 fish and planted 9,630 plants along a 2.9km stretch of the river, ms Wagner said.
"Experts tell us they have already seen evidence of increased trout spawning, fish diversity and an improvement with the in-stream habitat at various locations along the river."
Days after building the specially-created eel boulder holes, scientists found a large long-fin eel had taken up residence in one of them, she said.
"This much healthier river will be an even more beautiful attraction bringing people back to Christchurch to stroll along the promenade and enjoy the vibrancy of the central city."