THE NSW Department of Planning has defended its population projections for Kiama following claims they were overestimated.
The department released figures in The Illawarra over the next 20 years: A Discussion Paper in August, saying the municipality's population will have risen by 8050 between 2011 and 2031.
It has estimated the required housing at 4800 dwellings.
However, Kiama Municipal Council challenged the figures, with the Australian Bureau of Statistics recording an increase of just 193 from 2001-11.
The Kiama Independent also consulted the ABS and found an increase of 729 people for the same period.
Kiama Mayor Brian Petschler said the council had allowed for 1890 extra dwellings, in line with the Kiama Urban Strategy, which was based on the 2006 Census.
"To say we're going to grow by a population that is double the existing population of Gerringong doesn't appear to be realistic given the rate of growth experienced in the last 10 years," he said.
"Sure, there will be significant numbers increasing in Shellharbour and Wollongong as they develop West Dapto and those other areas, but we haven't been able to determine on what basis they've applied those figures to us."
Cr Petschler said past dwelling projections were based on 2.5 people a dwelling, but that has been reduced to 1.7 in the new projections and he argued the figure was unrealistic.
"The important flow-on question then is, where are you going to put them?" he said.
The department's southern region director, Brett Whitworth said there were errors in the ABS data.
He said the department had used the 2011 Census to calculate population projections statewide and divided them by region and then by local government area, also taking into account births, deaths and migration.
"But [the dwelling projections] may well be influenced by whether there's housing available," he said.
"It might happen that more housing goes into Wollongong and less into Shellharbour and maybe less into Kiama - we really want people's views."
He also said that Kiama's rapidly ageing population led to falls in the number of people in each dwelling.
Cr Petschler said the council was satisfied with its urban strategy.
"One of the things which may be thrown in is perhaps we only had a small increase because we haven't allowed for much development - I don't think that stands up to scrutiny," he said.
"The ratio of affordability here hasn't changed and if you look at any statistics, although it's expensive to buy here, there hasn't been a sudden rise here that hasn't happened elsewhere."
Foxground resident Howard Jones attended last Wednesday's forum at Kiama Leagues Club and said housing would never be cheap in Kiama unless agricultural land was covered in houses.
Mr Whitworth encouraged all residents to make a submission to the discussion paper, which will be considered for the Illawarra Regional Growth Plan.
To view the paper and make a submission, visit planning.nsw.gov.au/illawarra.