Questions remain unanswered about the impact a new "super prison" will have on Wrexham, according to an academic.
Extra policing and health care issues must be considered, said Robert Jones from Cardiff University.
His comments come as Wrexham MP Ian Lucas raises concern about the pressure on the rail network from an increase in passengers visiting the prison.
The health board says it is involved in the planning process and police are conducting their own research.
The £250m "super prison" - due for completion in 2017 - will hold 2,000 inmates, making it the largest prison in the UK.
"It is vital that the these matters are addressed in full before a single brick of the new prison has been laid," said Mr Jones, a research associate at the Wales Governance Centre at Cardiff University, which examines issues affecting Wales covering law, politics and government.
He has been researching the super prison since the Ministry of Justice announced its plans for Wrexham in September 2013.
"Since outline planning permission was granted by the planning committee in January 2014, numerous pieces of evidence have been uncovered which highlight the need for the impact of the Wrexham super prison to be fully assessed," said Mr Jones.
In June, Betsi Cadwaladr University Health Board said the new prison would have "significant investment implications" for the health service locally and that it was fully involved in planning for the project.
At the time the Welsh government said the costs and impact of the £212m prison on the NHS would be closely scrutinised.
Now, the research centre has considered additional policing issues concerning incidents at Wales's other prisons last year and says similar cases need to be considered in Wrexham.
Winston Roddick, North Wales Police and Crime Commissioner, said: "North Wales Police is currently looking into any potential implications in terms of policing.
"The ongoing research includes studying other areas where prisons are located to see if we can learn from their experience."
Meanwhile, local MP Mr Lucas told the Leader newspaper that figures he had seen showed a Scottish prison the third of the size of Wrexham's planned prison has seen passenger numbers rise by nearly 10,000 in the five years since it opened due to visitors to the prison.
And although he acknowledged the Wrexham line was undergoing a £44m upgrade, he questioned whether enough was being done to deal with any increase in passengers.
Network Rail told the Leader a five-year programme to invest in and modernise Welsh railways would include improvements to Wrexham and the surrounding area.
On Monday, Wrexham planning committee deferred a decision on outstanding planning issues for the "super prison" site on Wrexham Industrial Estate concerning landscaping matters, parking and drainage.
However, that does not affect the main planning approval, which has already been granted.
In August, diggers began preparatory works on the former Firestone factory site which will house the prison.