The Government inquiry into the Havelock North water contamination begins with a public hearing on Thursday.
Among the matters to be discussed will be whether to conduct the inquiry into August's widespread gastro outbreak in two stages.
In a minute to the Department of Internal Affairs released last week, inquiry panel chairwoman the Honourable Lyn Stevens QC said meetings already conducted with interested parties in October had identified a possible desire to conduct and report on the inquiry in two stages.
Stage 1 would cover the cause(s) of the outbreak, whether any person or organisation was at fault, and the adequacy of drinking water supply management for Havelock North, and the preparedness and responses of local and central government agencies and any other relevant parties.
Stage 2 would cover systemic matters and possible changes needed for the future.
"The inquiry is aware of interested parties who would only want to be heard on the second topics - and input on this would be welcome at the initial hearing."
The proceedings of Thursday's hearing, which may continue to Thursday morning, were expected to begin with opening comments from the panel chairperson, followed by identifying which submitters would want to be heard and present evidence and/or submissions.
The inquiry would also note the parties who wish to be designated as "core participants", and would release its decision on this shortly after the initial hearing, she said.
The public hearing will be held at the Hastings District Court at 10am on Thursday. The inquiry is required to report back no later than March 31 next year.
Justice Stevens will be joined on the panel by NZQA CEO and former director-general of health Dr Karen Poutasi CNZM, and local government and engineering expert Anthony Wilson.