Mayor Jodie Harrison said the statewide benchmark reflected the best scientific advice, and offered consistency.

In 2008, Lake Macquarie City Council became one of the first coastal councils to adopt a sea level rise policy for planning and risk management.

In 2009, the then Labor state government introduced its NSW Sea Level Rise Policy Statement, which Cr Harrison said followed "an approach very similar to ours".

But in 2012, the Liberal state government repealed the policy in a move it said was about restoring clarity for councils by dropping "Labor's onerous statewide sea level rise planning benchmarks".

The withdrawal of the planning benchmarks meant that councils were no longer compelled to use statewide sea level rise projections of 0.4 metres by the year 2050, and 0.9 metres by 2100.

The reform was said to allow councils to prepare section 149 certificates by focusing on known hazards, rather than predicted ones.

Lake Macquarie City Council opted to stick with its policy.

Affected residents have been unhappy, claiming that such council-imposed notations on section 149 certificates had unfairly devalued their properties.

Council has also since stated it does "not support new development" on land below the council's 100-year flood level of 1.5 metres above sea level.

Now the council is urging the NSW government to reinstate a consistent planning benchmark for sea level rise along the NSW coast.

In a council-endorsed submission to Environment Minister Rob Stokes, Cr Harrison said the statewide benchmarks of 2009 reflected the best scientific advice.

"The withdrawal of the planning benchmarks in 2011 has led to inconsistencies between coastal councils, even neighbouring councils, and made the job of Lake Macquarie City Council in managing and planning for coastal hazards more difficult," she wrote.

"Scientific projections for sea level rise show there is no real difference in oceanic sea levels along the coast, so statewide benchmarks would be applicable."