Upwards of 1500 temporary workers would flood the Eastern Southland area during two years of construction of a coal-to-fertiliser plant and a coal-to-diesel operation being investigated by Solid Energy and Ravensdown.
The plants would use lignite coal mined in the area.
It is estimated the two developments together will cost more than $11 billion and provide millions more every year in wages.
More than 500 permanent staff would be needed for the two ventures once they were operating between 2014 and 2016 and the Gore District Council would be in the thick of it.
The companies are conducting feasibility studies into the projects and will confirm early next year if one or both are to go ahead.
That potential situation has prompted Gore council planning consultant Keith Hovell to advise the issue should be raised at next week's council regulatory and planning committee meeting.
He said the committee should examine how the entire district could be affected.
The sheer amount of paperwork involved in such a large-scale project would directly affect the council - Mr Hovell said extra staff would be needed to handle the consents process and other issues.
"Council staff are already fully committed with their present workload . . . once details of the development and its potential impacts are understood, a staffing review will be undertaken and reported to the council," he said in a report to the council.
While the Gore council would be directly affected, there would be significant impacts felt throughout Southland, requiring a regional co-ordination plan.
Southland local authorities regularly meet at a shared services forum and the lignite developments and their impacts will be discussed at the next meeting, later this month.
Mr Hovell said a core group would need to be formed to look at the impending workload and how the projects could be supported at a regional level.
"Overall, the announcement provides some exciting opportunities for the district and region."
The council had a responsibility to ensure the physical and social environments were protected while also trying
Lignite plants' impacts
Environmental: Carbon dioxide discharges; noise; dust; transportation; water quality.
Infrastructure: Electricity supply; sewage disposal.
Social: Housing for construction and permanent workforces; capacity of social services (schools, medical, police, emergency services); adequacy of recreational facilities.
Flow-on implications: Need for expanded residential capacity in Gore, Invercargill and elsewhere; implications for expansion of commercial areas; roles of Gore and Mataura to meet those challenges.
Source: Gore District Council
