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.