As California’s drought continues to grip the state, regulators and a group of farmers have agreed to rare voluntary water cutbacks.

The farmers are all located in the fertile San Joaquin River Delta and have agreed to a plan that will require them to either cut their water use by 25%, or leave 25% of their land fallow. The plan was proposed by the farmers and accepted Friday by the State Water Resources Control Board.

Tim Moran, a spokesman for the board, told BuzzFeed News the plan affects those who have land that abuts rivers. Those landowners have the right to pull water directly out of those rivers — a concept known as “riparian rights.” Moran said there are as many as 2,000 farms in the area that fall into the category, about half of which are candidates for the program.

“Part of their motivation is they want to demonstrate that they are participating and trying to help the drought situation,” Moran added.

But the cuts represent a kind of imperfect solution for many farmers, some of whom believe the state has no right to cut their water use in the first place.