One lane of a busy road was closed to traffic due to emergency repairs on Wednesday during rush hour.
A number of businesses reported problems with their water supply and some were even forced to close for a short time.
NI Water said that it had now successfully completed the repairs in the city centre area and was working on another burst on the Grosvenor Road.
They said work should be completed by midnight.
"Restoring customers' supply has been our first priority," the spokesperson added.
"Unfortunately, burst water mains are by their nature unplanned and NI Water would like to thank the public for their patience during this time.  We appreciate how busy businesses are at this time of year and we apologise for the inconvenience.
"It is possible that there may still be some water discolouration, although this should clear in the near future."
Simon McCance of Ginger Bistro was among the restaurants in Belfast that had to close earlier.
However, he said his water was back on at about 17:20 GMT and his restaurant had re-opened.
"Aside from loss of revenue, it's just really disappointing because we've had a good year, but, what can we do?," he said.
Mr McCance said he had about 70 people booked in for the evening and expected about 30 more 'walk-ins'.
"It's a pain more than anything, it's a disruption on a very busy week," he said.
NI Water has apologised for any inconvenience and has urged customers to contact Waterline on 03457 440088 or go to its website for further updates.

The Sahara chief was arrested on Friday after he failed to appear before the judges in connection with a fraud case.
Two Sahara firms were ordered to repay 240bn rupees ($3.9bn; Â£2.3bn) to investors that market regulators said they had raised illegally.
On Tuesday, a protester threw ink on Mr Roy's face as he arrived at the court.
"Subrata Roy is a thief. He has cheated and robbed us," his attacker shouted. The man, identified as a lawyer by Indian television channels, was taken away by the police.
Profile: Subrata Roy
It was not immediately clear whether the businessman would now be sent to jail. Since his arrest, he has been lodged in government guest houses.
The Supreme Court set the next hearing for 11 March.
On Tuesday, Mr Roy apologised to the court saying his reasons for not appearing before the judges last Wednesday "were genuine".
He said Sahara would sell its assets and pay back the investors and asked the judges to give him more time.
But the court rejected his proposal saying "we are not interested in selling the properties, you have been telling us for the last two years, it is your headache, you should have done it".
The judges also ordered police to take two other Sahara directors into custody and hold them until the next hearing.
The case against Mr Roy stretches back to August 2012, when the court ordered the two Sahara firms implicated to refund money to 22 million small investors within 90 days and with 15% interest.
In December 2012, the court gave the firms more time to repay.
In February last year, market regulators  froze the firms' bank accounts saying they had failed to refund the money.
But Sahara disputes the amount it should pay back, saying its liability should be no more than the 51.2bn rupees it has already paid back.
Mr Roy is a household name in India.
His group, worth $11bn, has businesses ranging from finance, housing and manufacturing to aviation and the media.
It also has interests overseas - it owns New York's landmark Plaza Hotel and London's iconic Grosvenor House.
Sahara also sponsors the Indian hockey team and owns a stake in Formula One racing team, Force India.
With more than 1.1 million workers, the group is India's biggest private sector employer.
Disruption caused by burst water pipes in Belfast city centre has ended.
[NEXT_CONCEPT]
India's Supreme Court has ordered the continuing detention of businessman Subrata Roy and asked his firm to come up with a plan to repay its investors.