He said the council would facilitate testing and monitoring from the regional council, and DWA (Drinking Water Assessor).
The council had developed a monitoring plan after the outbreak, which Mr Thew said they would alter to reflect recommendations made to the hearing about the treatment, and monitoring of the water supply.
He agreed an Emergency Response Plan (ERP) was needed to be in place before adverse events occurred, and discussed what such a plan would entail - accepting it should be tested every 3 months, and set out emergency response actions such as a pre-prepared text for boil water notice, and a full communication plan.
It also needed to be accessible at all times, and lay out how to interact with other agencies, and their respective roles.
Although Mr Thew stated a lot of the elements of an ERP currently existed throughout a number of documents the council had, he agreed it needed to be simple, and practised amongst staff.
Earlier this morning, he stressed that the Hastings council was putting utmost priority on ensuring Havelock North had a safe water supply, and that it would not take a penny-pinching approach to achieving that.
He confirmed to counsel assisting the inquiry, barrister Nathan Gedye, there was no intention to re-activate Brookvale Road bores 1 or 2 and that Brookvale 3 would be enough to supply peak summer water demand to the village.
Under questioning about instances of E-Coli being detected in the Hastings water through August to October, along with GNS Science testing that had found significant levels of young water in the bores, Mr Thew said the council had "complicated and extensive" issues to grapple with.
Even if the water was being treated heavily there would still be a focus on the state of the raw water in the catchment, to give the community confidence that the council knew what was going on in the aquifer, he said.
This was something that Central North Island Drinking Water Assessment Unit drinking water assessor Peter Wood wanted to know more about before he could sign off on what Hastings was proposing, and the Hawke's Bay DHB was also keen to participate in aquifer conversations.
Mr Thew also confirmed that the Hastings District Council would follow its water safety plan and regularly liaise with the regional council to improve its knowledge of the aquifer recharge zones, contaminated sites, source protection, activities in the recharge zone and monitoring well results.
Last month it was announced the inquiry would be postponed until late January 2017, because of a legal battle between two Hawke's Bay councils - the Hawke's Bay Regional, and Hastings District Councils.
However, in their decision to postpone the hearing, the Inquiry stated if any party had concerns about the safety of the Havelock North drinking water supply over the coming months, they could opt to convene a hearing on that issue.
In November Hastings District Council advised they had no option but to reactivate Brookvale Bore 3, which had been out of operation, to augment the Hastings supply during periods of peak usage.
The inquiry's terms of reference also direct the inquiry to explore actions to ensure a safe water supply could be provided to the Hastings suburb.
Due to this, the panel considered the proposed reactivation required an assessment of interim measures needed to ensure the safe supply of water to residents.
Classed as Issue 8 - over the next two days the Inquiry will focus on the actions, or further actions required to ensure a safe supply of water to Havelock North over the next 12 months.
The district council has provided a proposal for this - in their memorandum to the Inquiry, they stated to ensure the safety of the supply, the council had resolved to implement a comprehensive treatment regime, where water pumped from the bore would be treated by filtration, UV treatment, and chlorination.
Bore 3 would not be reactivated until the infrastructure for the treatment had been constructed, commissioned, tested, and approved by the Drinking Water Authority.
At today's hearing, the Inquiry will hear the response to the council's proposal from parties, who will also speak on what matters they believe should be taken into account in assessing whether the Havelock North water supply remain safe over the 12 month period.
The Hawke's Bay District Health Board had proposed the creation of a joint working group, made of representatives from Hastings District Council, the Hawke's Bay Regional Council, the DHB, and Peter Wood of Mid Central DHB, chaired by an independent chairperson.
Four individuals involved in the group - which had already met, with minutes from this meeting given to the inquiry - will be cross examined today.