The Washington State governor has declared statewide drought emergency.
Gov. Jay Inslee says snowpack in his state is at historic lows, river levels are dwindling and irrigation districts are cutting off water to farmers.
Snowpack in the mountains has dropped to just 16 per cent of normal levels statewide.
He says impacts are already severe in several areas of the state and decisions are being made about what crops get priority water and how best to save fish.
Local authorities say the drought is unlike any they have ever experienced.