According to City of Newcastle, disclosure of the "confidential" 116-page report, completed in late 2018, would "create confusion among the community".

The agencies also refused to reveal the name of the consultant who authored the report, claiming it contained "sensitive business and technical information".

In official responses that echoed each other and arrived on the same day, City of Newcastle and the Department of Planning, Industry and Environment said releasing the report would "provide an unfair advantage" to the consultant's competitors.

But City of Newcastle then went on to say the technical information contained in the report "was no longer accurate" because it was outdated.

The Newcastle Herald requested a copy of the Stockton Synthesis Report [also known as the Stockton Coastal Management Synthesis Report] under Government Information Public Access (GIPA) laws in February and March.

The requests were made on the grounds that residents ought to be fully informed what investigations City of Newcastle has undertaken before it reveals long-term options for the beach in its much-anticipated draft Coastal Management Program (CMP), due on May 13.

Two months and a bill for $112 later, City of Newcastle replied last week denying access to the report besides two pages, on the same day the NSW government completely refused access.

The two heavily redacted pages released by City of Newcastle included the front page with large chunks blanked out except for the report's title and completion date, and a second all black page with the word 'Confidential' at the top.

The lack of information gives plenty to fuel concern.

Stockton resident Lucas Gresham described the secrecy as disappointing.

"The truth is we need to be open and transparent and work together on this, not against each other," he said. "This report shouldn't be hidden. It makes you question what they are hiding."

It's understood the author of the highly-guarded report is Royal HaskoningDHV. The same consultant currently employed by City of Newcastle to help complete the CMP.

Both reports investigate long-term solutions for Stockton beach.

While it's unknown exactly how much ratepayer money was spent on the confidential report, it's understood similar consultant reports range in price from $100,000 to $250,000, depending on the scope and nature of the investigation.

The Newcastle Herald understands City of Newcastle is desperately fighting to keep the document secret because it recommended hard structures for the shoreline and residents have been clear they want sand nourishment.

It's also understood the soon-to-be-released CMP will have no set plan for sand nourishment and will focus on protecting assets, not beach amenity.

Residents will be expected to take a leap of faith and hope that Deputy Premier John Barilaro's Stockton beach taskforce, that has not met and has no set terms of reference yet, will find a sand nourishment solution.

There is concern in the community if funding is sought for hard structures to wall the shoreline under City of Newcastle's 'last line of defence' CMP, when it comes to asking the NSW government for more money for sand, the answer will be no.

Former environmental consultant Peter Jamieson, who studied Stockton beach for years, warned a seawall was not the solution. He said without sand, all beach amenity would be lost.

"It would look just like Queens Wharf, except it would have bigger waves crashing over the top of the rockwall," he said.

Mr Gresham said it was clear from the Stockton surf club rockwall that City of Newcastle built against expert advice in 2016 - that saw erosion increase on sections of the beach forcing the removal of cabins from the caravan park - that the unfolding erosion crisis was difficult to manage.

"We all know that they have not always gotten this right, but I think the community is more willing now than any other time to work with government to find a solution," he said.

"But we need to have faith that they are being upfront with us."

Concern about lack of transparency comes just weeks after City of Newcastle's chief coastal scientist Mark Manning, who was working on the Stockton CMP, suddenly quit.

A letter to the Newcastle Herald from City of Newcastle's legal and information officer last week, on behalf of chief executive Jeremy Bath, refused access to the Stockton Synthesis Report, but provided redacted copies of documents that refer to the report. Other documents about the CMP were also provided.

The only insight from the documents into the report's actual contents is contained in City of Newcastle and Office of Environment and Heritage (OEH) meeting minutes from February and April 2018.

A line in the April meeting reads: "OEH did not support the relocation of the Mitchell Street seawall".

Among the other reasons outlined for refusal to hand the report over by both agencies was that it is confidential and "was not made public or distributed to the community".

"I have been advised that the release of the report now would be prejudicial to both CN [City of Newcastle] and the consultants," council's information officer wrote.

"This is because it would create confusion among the community and put unreasonable pressure on the consultants and CN's resources to respond to community demands while the draft Coastal Management Program is on public exhibition."

The mysterious Stockton Synthesis Report was prepared to outline potential long-term actions for Stockton beach as part of the Newcastle Coastal Zone Management Plan (CZMP) under previous legislation.

Councils are now required to produce a similar plan called a CMP under new legislation introduced in 2018.

According to City of Newcastle, the Stockton Synthesis Report was not used because the CZMP did not proceed due to the legislation change.

"I have been advised that the coastal erosion has progressed, and the information in the report has now become irrelevant," the council officer wrote.

This is despite a City of Newcastle file note from February 2018 that reads: "The work that has been undertaken [as part of the CZMP] will feed into the CMP development".

Council's information officer said on balance she believed disclosure of the report and the identity of the consultant was not in the public interest.

In making her decision, she agreed with City of Newcastle's argument that it would impede delivery of the CMP, after the deadline was moved forward six months to June 30 by the NSW government, by putting "outdated and inaccurate information" in the public domain.

"While I understand that there is legitimate interest by the community and the media in understanding how the relevant agencies, and CN [City of Newcastle] in particular have managed the issue of the Stockton erosion, I am of the opinion that the release of the communications identified will provide sufficient insight," she wrote.

An environmental consultant, who regularly works for government agencies, said she would expect some of the work from the previous report to inform the new report.

"Even if things have changed significantly, I would imagine that there would still be some information in the older report that would be useful," she said.

"I find it very hard to believe that none of the work done on the same location over a relatively short timeframe, both looking at long-term solutions, would not be relevant in some way."

The Newcastle Herald asked University of Newcastle's Conjoint Associate Professor in Earth Sciences Ron Boyd - a Stockton resident who is part of City of Newcastle's Stockton Community Liason Group that was put together to help find a solution to the worsening erosion - if he had seen the report.

"I have a copy of every other report and I don't have a copy of that report," he said. "I can tell you I am not familiar with it and I don't think I've seen it."

Despite refusing to hand over the requested report, City of Newcastle did provide some not requested information.

"I have also decided to provide you additional emails which do not fall within the scope of your application, but which I believe will be of interest," she wrote.

Among these documents was an email exchange in September between City of Newcastle's former head coastal scientist Mr Manning and Department of Planning, Industry and Environment's senior team leader Steven Crick.

Mr Crick offered advice in response to a range of questions including "the potential extension of the Mitchell Street seawall/contiguous piling for protection of Stone Street".

"Council should consider alternative options to construction of a seawall, including works that will allow more detailed consideration of long-term options through development of the CMP," he wrote.

"For example, a pilot beach nourishment project could be undertaken using sand from approved onshore sources... Council could also investigate extension of the existing Mitchell Street seawall further to the north to a point where end effects could be more easily managed."

Royal HaskoningDHV said it was unable to comment and directed questions back to City of Newcastle.

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