However, questions remain about how long the mouth will remain cleared.
Council roading maintenance engineer Peter Standring said it had got to a point where the council needed to act to maintain access in Hoopers Inlet Rd.
The inlet had risen to a height where it was lapping at the edges of the road.
''Now was the time to act. It needed a fair bit of water behind it to clear.''
The council would keep a close eye on the inlet for the next few days, with the hope it would stay unblocked, he said.
''There is every possibility it could be choked back up tomorrow.''
Hoopers Inlet resident and Otago regional councillor Sam Neill said it was a relief to see the mouth opened before any more damage was done to the roads in the area.
''It means our access remains open. We were always in danger of being cut off.
''The roads are extremely busy with tourist traffic. This has made it easier and safer for them to travel on.
''I'm grateful to the DCC for doing it.''
Hoopers Inlet Rd resident Steve Cutler was also pleased the mouth had been cleared because the blockage had caused the inlet's water levels to rise to the point where he was having to drive through sea water to get his children to school.
''It will be good to get the inlet back to its natural tidal cycle.''
While resident Hamish Forrester was delighted the council had acted, he was concerned about whether the mouth would remain unblocked.
''Time will tell whether it stays open.
''I'll be pleased when sufficient tidal exchange is established.''
The work was funded through the council's roading maintenance budget.
