Clydebank farmer Sandra Jefford is no stranger to floods. The two properties she owns and operates with husband Wilco Droppert are in low-lying coastal areas and at high risk of being inundated with water.
“They wash away farm tracks, fencing and bury pastures underwater and cover them in silt,” Jefford told the Monitor.
The couple have a 370ha farm in Clydebank with about 380 cows and a 178ha plot at Stratford, between the Avon River and Nuntin Creek, where they grow feed and run beef cattle.
Both farms have flooded in the past, and Jefford fears an increase in the frequency of events.
“It takes a long time to recover from floods. It's really expensive and if these events happen more often, it's going to be more expensive for farmers.”
A new report from the Climate Council, drawing on fresh research from the University of Melbourne, shows how sea level rise will make severe flooding events more intense and cost Gippslanders billions of dollars.
What’s happening: The report states more than 267,000 coastal properties and two million hectares of land around Australia will be damaged by flooding this century as sea levels rise.
It estimates this could cost Australia $855 billion over the next 74 years, and that Gippsland could incur $24 billion in losses to housing, farms and infrastructure.
East Gippsland’s coast faces losses of $18 billion, according to the report.
In Gippsland, most of the area predicted to be hit by rising tides is low-lying farmland along the coast.
How do rising sea levels increase flooding?
University of Melbourne coastal geomorphologist, Professor David Kennedy, told the Monitor there are two factors that make flooding events more common as sea levels rise.
First, when the level of the sea is higher, it makes it harder for water to flow from rivers and catchment areas into the ocean.
“When areas flood, the water wants to get down to the sea but with 1.4 metres of sea level rise that becomes more difficult, because the level it's trying to drain to is higher. That's why we get more flooding when there's a spring high tide.”
The Victorian Government requires planning for a sea-level rise of not less than 0.8 metres by the year 2100, but Kennedy said that estimate was conservative and 1.2 to 1.4 metres was more likely.
He said a good way to think about it was that in 100 years the current high tide will be the new low tide.
Secondly, on low-lying farmland, a higher sea level means the water from the ocean is trying to get over levee walls and barriers with a greater amount of force.
“A lot of these farmland areas are already highly at risk of flooding. What rising sea levels means is water wants to be across it with more urgency than normal.”
Why are sea levels rising?
Sea levels around the globe are rising as warming ocean waters expand and melt glaciers and ice sheets. This warming is a consequence of a growing concentration of greenhouse gas emissions in the atmosphere from the burning of fossil fuels.
Be prepared
“If there's going to be a flood,” Jefford said, “we have to have our cattle either on the higher ground or have them at the front of the farm and be ready to move them off.”