The governor of California has implemented the first mandatory water restrictions in the state's history.
The order implements a 25% reduction in water usage for cities and towns across the parched state.
Vast areas of government-owned lawns will be replaced by drought-tolerant landscaping, and towns will be banned from watering ornamental grass.
Last year, Governor Jerry Brown proclaimed a state of emergency after years of drought.
The snow in the mountains is at its lowest level since records began, so water supplies from melting snow will be lower than normal in coming months.
"We are standing on dried grass, and we should be standing in five feet of snow," said Mr Brown, speaking in the Sierra Nevada mountains.
"People should realise we're in a new era. The idea of your nice little green grass getting lots of water every day - that's going to be a thing of the past," he said.
The new order will require university campuses, cemeteries, golf courses and other large landowners to make major cuts in their water usage.
Farmers in the United States' largest farm state have been hit hard in recent years.
But Mr Brown's critics said his order did not go far enough to address agricultural use of water.
"In the midst of a severe drought, the governor continues to allow corporate farms and oil interests to deplete and pollute our precious groundwater resources that are crucial for saving water,'' said Adam Scow, California director of the group Food & Water Watch.
Previous extremely dry years led to catastrophic wildfire seasons in California in 2003 and 2007.