The "extensive review" was the result of a fair, open, and transparent process, he said, and many views had been represented.
"I think we all have a very firm view on where things are at on this in this water storage scheme.
When asked, he did not think there was any new information presented in the review, but there was "a lot of clarity on existing information".
For other councillors, the review has confirmed their stance on the scheme. A formal decision on its future is expected to be made on May 31.
Napier councillor Alan Dick said the review had been a very "thorough exercise", which strongly supported the scheme going ahead.
"It makes it clear the project must proceed and if it doesn't there will be really severe problems for this region and its land-based economy, if council tries to implement plan change 6 without the Ruataniwha scheme," he said.
"If we were to implement [the plan change] without the water scheme ... then we're in big trouble."
However, for Napier councillor Paul Bailey, what he had seen of the review so far had "amplified my concerns about the scheme".
He said this was particularly around the economic and environmental aspects of the scheme, as "there has been new information come to light in the financial analysis because I believe HBRIC has been more open about what has been going on".
His elevated environmental concerns were because "there's been a much more in-depth analysis about what is needed to meet the DIN level under plan change 6".
Councillors agreed compiling information about the scheme had been very helpful.
Napier councillor Neil Kirton said the review process had made him feel more cautious, but it was a benefit having all the key material compiled.
"For me it certainly has been a worthwhile exercise ... I don't think I would have been in any position to have made a decision without having done it, and without this extensive history and involvement, and detail."
Wairoa councillor Fenton Wilson said there had been "nothing terribly new" about the content of the report, which condensed years of work on the scheme.
"This has been a very long cup of tea," he said. "The time to roll our sleeves up and get back into the work process is upon us."
Mr Graham also said council planned on making everything related to the review available to the public, aside from some redacted sensitive information.