California's worst drought in 1,200 years in pictures

The governor of California has recently imposed the state's first mandatory water restrictions, as nearly 40 million people enter the fourth year of severe drought. Farmers, business owners, and residents will be forced to cut their usage by 25% as scientists warn of the worst drought in 1,200 years.

People in the San Francisco Bay Area have been the most economical, while some communities in Southern California have been the most wasteful.

A buoy sits on the dry and cracked bed of what used to be Shasta Lake.

The sun rises over a farm near Firebaugh, California. Some towns in the United States' largest farm state have seen high unemployment as farms have lain fallow.

The new mandatory water restrictions do not apply to farmers. They only have to submit a detailed drought management plan, which will have to include a plan for cutting back.

In January of 2014, Governor Jerry Brown asked Californians to voluntarily reduce water usage by 20% - which did not happen.

California's snowpack - which melts to supply a third of the state's water supply - is all but gone.

Critics of the plan say that it is not strict enough on farmers - the biggest users of water in California.

Farmers warn that the cost of their products will rise as more fields go unplanted.