Vector, the company responsible for maintaining the Maui pipeline, said it expects to have the pipeline repaired by Sunday, weather permitting.
Vector chairman Michael Stiassny told the company's annual meeting in Auckland that Monday's breach had been a significant event for gas customers, and for New Zealand.
"It's the first time in 33 years that an issue has arisen on this pipeline, and I hope it is another 33 years before there is another one,'' he said.
Vector had reconfigured its own pipeline, which runs alongside the Maui pipeline, to ensure as much supply as possible could be made available to affected customers.
"We expect to have the [Maui] pipeline repaired and gas restored by Sunday evening, subject of course to no further issues arising during this time or the weather deteriorating,'' Stiassny said.
Gas supply has been restored to essential services including hospitals, most of the dairy companies, small businesses and small users of gas.
Residential customers have not been affected, but Stiassny said the situation still depended on customers being frugal.
Vector said early today that gas had been restored to an additional 1,000 customers which included small industry, larger hotels, shopping malls and commercial buildings.
Stiassny said the company did not have financial exposure to the pipeline, which is privately owned by Shell New Zealand's Maui Development Ltd.
Looking ahead, Stiassny said the company's earnings before interest, tax, depreciation and amortisation (EBITDA) for 2011/12 would be slightly higher than the current market consensus, which sits at around $610 million, but down from the company's EBITDA for 2010/11 of $636.5m.
Vector _ New Zealand's biggest owner and manager of energy infrastructure networks _ is just over 75 per cent owned by the Auckland Electricity Consumers Trust.
The company's shares last traded at $2.55, unchanged from Thursday's close.