HOUSES on the shore of Lake Macquarie will be considered for demolition under a city council plan to adapt to rising sea levels.
The council became, in 2008, one of the first councils in Australia to approve a sea-level-rise policy.
Now it is developing an ‘‘adaptation plan’’ in the low-lying suburbs of Marks Point and Belmont South.
The plan is expected to take 18 months to complete and will involve community consultation.
Other areas to have plans done in future include Belmont, Swansea, Blacksmiths, Pelican, Dora Creek, Speers Point and Warners Bay.
Removing houses and other infrastructure, known as the ‘‘retreat’’ option, would be considered as a method to cope with the risk that climate change would lead to higher lake levels, the council said.
This involved allowing low-lying land to ‘‘revert to natural shorelines’’.
Councillor Barry Johnston said retreat would be ‘‘extremely unpalatable for the community’’.
Swansea MP Garry Edwards said compensation would be a ‘‘huge issue’’ if retreat was enacted.
Other options the council will consider include retaining walls built on private property, levees and landfill.
‘‘Retaining walls within private property, with a [rocky] beach [built] on the lakeside of the retaining wall, are preferable to sea walls for environmental and social reasons,’’ the council said.
This would retain public access to the shore and prevent rotting seagrass problems.
Cr Johnston said landowners could have to contribute financially to retaining walls because they would benefit.
‘‘But nothing has been decided,’’ he said.
Another option was ‘‘setting buildings back on longer blocks to be outside high flood-risk areas’’.
The council will collaborate with residents, businesses, community groups and service providers to establish adaptation plans.
The plans would provide a ‘‘framework for managing flood and sea level rise risks’’.
Asset value and lifespan, community and environmental values, and triggers for action would be examined.
Options would be determined to respond to ‘‘the uncertainty associated with climate change impacts’’.
‘‘A new house or road built today will still be around in 50 or 100 years,’’ the council said.
‘‘Council has a duty of care to make sure these assets, and the communities that use them, are safe for the full life of the asset.
‘‘By planning early, there is plenty of time to identify and plan for future risks.’’
As well as barriers to stop water, properties could be modified to reduce flood risks.
The council was already demanding that floor levels be raised for new buildings in low-lying areas.
It completed a study last year of lake flooding and the effects of projected sea level rise to the end of this century.
The study found up to 10,500 lakeside properties could be affected by lake flooding by 2100, the council said.
‘‘Properties already affected by flooding would be flooded more often,’’ the council said.
‘‘Some council infrastructure, such as roads and drains, could become unusable as rising lake levels and groundwater inundates low-lying areas.’’
Mr Edwards expressed some misgivings about the council’s sea level rise policy.
‘‘On the face of it, it seems reasonable to plan to protect people’s properties,’’ Mr Edwards said.
Residents favour dyke over properties buyout
MARKS Point residents would oppose plans for a government buyout of their properties over sea level rise concerns.
Peter Anderson, who lives on the waterfront in Marks Parade, said the council could not afford a buyout.
‘‘I can’t see them buying up all the properties around here,’’ Mr Anderson said.
He would prefer a dyke, also known as a levee, to be built to stop rising water.
Mr Anderson said the council was making people raise floor levels of new buildings and renovations in the area.
‘‘But I don’t see the council lifting roads around here,’’ he said.
‘‘What is their strategy and what vision do they have?
‘‘What about the sewer and services?’’
Rodney Kent, of Marks Parade, would prefer a wall or barrier to stop rising seas, rather than authorities buying up properties for demolition.
‘‘If walls don’t work, they might have to buy the houses out – but that would be a last resort for me,’’ he said.
‘‘I think the cheaper option would be to put a wall up.’’
Mr Kent was glad the council was examining the matter.