More fish have died in the Murray-Darling Basin after much-needed rain washed ash into waterways amid the bushfire crisis and ongoing drought.

The fish were killed in the Macquarie River, the Namoi, Gwydir, Border Rivers, Barwon-Darling, Lachlan, Upper Murray and Murrumbidgee rivers.

“We have seen fish deaths in recent weeks in several locations under stress due to fires and the ongoing drought,” the Murray-Darling Basin Authority’s Andrew Reynolds said on Thursday.

An estimated one million fish died in the Darling River near the NSW town of Menindee last summer in multiple kills in the drought-ravaged waterway.

In response to the latest deaths, basin governments are trying to relocate fish, install aerators and deliver strategic releases of water to the environment.

Despite the rain bringing relief to fire grounds and hope to farmers, there hasn’t been a major change to basin storage levels, which remain at 27 per cent.

Mr Reynolds said while levels will recover slightly in some catchments in coming weeks, the total volume of water in basin storages had declined in the past fortnight.

“We really need a long period of above-average rainfall to break current drought conditions,” he said.

He said threats to water quality, most notably from algal blooms, would continue with no flows at some locations and reduced ones at others.

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The basin authority’s latest drought update reported heavy rainfalls along the Great Dividing Range during the past two weeks.

Up to 115 millimetres fell at Armidale in NSW and 110 millimetres at Leslie Dam near Warwick in Queensland.

In the south, Jamieson on the Goulburn River recorded more than 70 millimetres, along with Rocky Valley at Falls Creek in Victoria.

The bureau is forecasting rain across the northern basin in coming days.

-AAP