More Homes, Rising Seas: The Gold Coast's Big Problem

About 60 years ago, a series of powerful storms hit the Gold Coast and stripped away millions of tonnes of sand from its beaches. The worst strike came in 1967, when a storm described as a 'cyclonic punch' showed just how exposed the city really was. To protect itself, the city spent decades building a major coastal defence system. This system includes a hidden seawall called the 'A-line,' which is made from boulders and sits five metres thick underground. Sand pumps, artificial reefs, and sand dunes also help keep the ocean from flooding the city.

But rising seas are now creating new challenges that are harder to fix with walls and pumps. The Gold Coast City Council recently released updated maps showing which areas face the greatest dangers from natural hazards like storm tides and landslides. Earlier maps from 2022 had already shown that about 88,000 extra properties could flood during extreme weather events. A council report also found that climate data had not always been used when planning new buildings and roads. Mayor Tom Tate said the report showed some things the city had missed, but promised that climate risks would be part of the council's new planning rules within 12 months.

However, Mayor Tate also said that new housing estates planned for the city's northern areas, like Norwell, could still be built safely. He said those areas are mapped as 'very high risk' for flooding, but that man-made lakes and water bodies could hold the extra rainwater. 'When it rains the water elements swell, but it doesn't swell to the extent that it floods houses,' he said. Not everyone agrees with that view. Dr. Aysin Dedekorkut-Howes, a planning expert at Griffith University, said those northern suburbs sit on land that is naturally wet and low-lying, similar to a river estuary. 'We keep building in those areas and we are putting people at risk,' she warned.

Dr. Dedekorkut-Howes has studied climate risks across Australia and says the Gold Coast is the country's most at-risk city when it comes to the financial cost of rising seas. She points out that the A-line seawall, while impressive, can only do so much. 'Engineering can only help us so much. It can postpone some of the inevitable risks for 20, 30 years,' she said. The Queensland government predicts seas around the Gold Coast could rise by 0.8 metres by the year 2100. But Dr. Dedekorkut-Howes says some newer climate models suggest the rise could be between 1.5 and 2 metres, which would put many more areas at risk of regular flooding.

Rising sea levels also mean that floods which used to happen rarely will start happening much more often. Dr. Dedekorkut-Howes explained that when flooding is rare, people tend to think of it as an acceptable risk. But as climate change makes floods more frequent, what once seemed like a small danger grows into a serious problem. Canal housing estates — neighbourhoods built around man-made waterways — are especially vulnerable because they sit very close to the water. She warned that there may come a time when insurance companies stop offering coverage for these areas, or make it too expensive for most people to afford.

The cost of insurance is already a concern for experts watching the Gold Coast's development. Ned Wales, an assistant professor at Bond University who studies sustainable development, said that building in risky areas could end up costing homeowners a lot of money in the long run. He pointed out that some homes built in the last 20 years may have been approved using old data that did not account for today's flood risks. Meanwhile, Councillor Glenn Tozer said the new hazard maps were simply meant to inform residents, and argued that the maps would not change insurance premiums or property values. But the Insurance Council of Australia said that insurers do use council maps when deciding how much to charge for coverage, and that updated maps could affect premiums if they show a real change in risk.

Scientists and planners say the city needs to act now to avoid bigger problems in the future. Dr. Dedekorkut-Howes said the shortage of affordable housing is already pushing planners to approve new builds in areas that face growing climate dangers. She believes the city must plan carefully and avoid adding more homes in the highest-risk zones. 'There are going to be areas in the future we need to move away from and that's not something that can be done overnight,' she said. With rising seas and a growing population, the Gold Coast faces one of the toughest challenges in its history — and the decisions made today will shape what the city looks like for decades to come.