Gardaí could be delayed by up to two hours in arriving at serious crime scenes due to plans to amalgamate garda divisions.
Middle-ranking officers are also warning of the impact the new model will have on community policing.
The operating model is currently being introduced on a phased basis and will take place over a number of years in what will be the biggest ever restructuring of the force.
Members of the Association of Garda Sergeants and Inspectors (AGSI) were given a presentation on the model at their annual conference in Killarney.
Tipperary and Clare will become one garda division, Meath and Westmeath will be merged, as will Wicklow and Wexford. The existing divisions of Cavan/Monaghan and Louth will become one, as will the current divisions of Laois/Offaly and Kildare.
In Cork, the Cork West and Cork North divisions are being amalgamated, resulting in a division stretching from the tip of the Beara peninsula in the west, to Youghal on the east.
Sergeant Alan Cronin from Cork city, who is AGSI deputy president, said members are unhappy there is no concrete timeframe for the creation of each new division.
He said that while the merger of some counties is a concern, the amalgamation of Tipperary and Clare is one of the “most controversial”.
Liam Corcoran, honourary secretary of the AGSI and a sergeant based in Tipperary told thethe amalgamation of those two counties will mean that the new division will be 7,800sq km in size:
"You are talking about from Bell Harbour in north Clare right down to Carrick-on-Suir [in Co Tipperary] on the Waterford border.
Tipperary will no longer have the divisional headquarters in Thurles as it will then be based in Ennis, Co Clare — a two-hour drive for gardaí based in Cahir or Cashel.
He warned that gardaí will also have to travel to crime scenes up to two hours away under the new model, while forensic collision investigators will also have lengthy journeys under the restructuring. Sgt Cronin also queried if the new divisions will have just one crime prevention officer each.
"The contact we have with people at the moment, we would like to maintain it," he said. "We would not like to see it negated in any way with this new model.”
"We would hate to see the community policing model just be a call for service and a guard arrives, details are taken, and that’s it.
He pointed out that victim support is embedded in legislation.
“We would not like to see the operating model, when it comes on stream, affect that in any way. We need to preserve those things.”
Garda Commissioner Drew Harris recently addressed the Clare Joint Policing Committee in relation to the amalgamation of the two counties. He told the: “We would be looking at approximately 12 months for now for that amalgamation on the present timescale that we have.”
According to garda headquarters, a wide range of operational factors were considered when deciding where the new regional and divisional headquarters should be based, including population, geography, projected growth, crime trends and “workload across a range of work streams”.
Mr Harris said there is ongoing “liaison” with the AGSI and the Garda Representative Association about the new model.
He said the force is currently recruiting sergeants and inspectors.
"One of the things I want to see are good levels of supervision and that is imperative in terms of running out the operating model and so doubtless the sergeants and inspectors will be pleased to know that the sergeants competition commenced and the inspectors competition is to start this month.”