A Government-ordered report into the failure of the Maui gas pipeline almost a year ago finds there are 11 areas along its length that remain at high risk.

The review also finds users were ill prepared for the outage but there appears to be little justification for building duplicate infrastructure and no evidence that critical response regulations should change.

The pipeline failure on October 24 forced milk factories, bakeries and large industrial users to close, costing an estimated $200 million for businesses in the top half of the North Island.

Hospitals were also affected by the failure caused by a landslip in northern Taranaki that took five days to fix.

Advertisement

The pipeline runs from south of New Plymouth to the Huntly power station and has been under increased scrutiny since the failure.

The repaired section at Pukearuhe remains within the landslide and measures were in place to prevent further damage.

Further geological assessment of the pipeline's sensitivity is under way at the site of the failure. Completion of these assessments is expected within the next three months.