Farmers pay for heatwave

The record-breaking heatwave across south-eastern Australia is predicted to ease today, but farmers are already counting the cost in the millions of dollars.

Temperatures in Adelaide hit 40.5 degrees yesterday, the 15th straight day they have soared above 35 degrees.

The heat has had a devastating effect on South Australia's farming sector and raised serious doubts about the sustainability of irrigation in the lower Murray River. "It's fair to say it's costing many millions of dollars a day, and the damage bill will get higher the longer it continues," South Australian Farmers Federation president Wayne Cornish said.

Mr Cornish said apple and pear growers had suffered severe damage from heat and wind.

"Most crops, like soft vegetables, can tolerate three or four days of extreme temperatures, but that's about the limit," Mr Cornish said.

The situation is at its most severe in the final reaches of the Murray River, including Lake Alexandrina, where water levels are so low even farmers with irrigation rights are finding their pumps left high and dry.

"Certainly because of the low levels and because of salinity, I don't know how many irrigators are using that water. I know some are carting in water because it's too salty for stock and plants," said Wendy Craik, chief executive of the Murray-Darling Basin Commission.