"This extra water could make that vital difference for farmers, allowing them to keep crops growing and stock alive," Environment Minister Gabrielle Upton said in a statement on Sunday.

Up to 15,000 megalitres of water previously reserved for environmental purposes will be made available within the Gwydir, Macquarie, Lachlan, Murrumbidgee and Murray-Lower Darling valleys.

The water will be sold at the prevailing market price.

"All proceeds raised from purchases of this water will be held in trust with the Department of Primary Industries and used for priority drought-related projects," the minister said, adding an additional 450 megalitres of groundwater would be made available in the Riverina.

The state's National Parks and Wildlife Service has also been told to make its trucks and trailers available to help transport feed and other "pressing needs".

Grazing permit holders in the Riverina and beekeepers using national parks across NSW will have their fees wavered for at least 12 months.

"These measures demonstrate a proper balance between protecting the environment and doing what we can to provide vital assistance to drought-stricken farmers," Ms Upton said.

National Farmers' Federation president Fiona Simpson says graziers desperately need water with some even running out of drinking supplies.

"At the moment there are people who have run out of rainwater," she told ABC TV on Sunday.

"We are struggling with that. We certainly need to make sure that basic human needs and basic animal welfare needs are always at the top of the list."

Oscar Pearse, a mixed cropping and beef production farmer near Moree, welcomed Ms Upton's announcement.

"It'll allow irrigators to use their existing resources and put some crops in," he told AAP.

"The potential for that water to be used to turn into fodder very quickly and help alleviate the supply issues for feeding livestock ... that'll make a big difference."

Australian Associated Press