SAN FRANCISCO — The three-year drought gripping California has shrunk reservoirs, rivers, creeks and snowpack while leaving residents drawing heavily on underground aquifers to water everything from lawns to crops.

Farmers account for about 80 percent of water used in the state, but Gov. Jerry Brown has asked California households to save water as well. Here's a look at how it's going and what the problems are.

Q: How are California residents doing when it comes to meeting the state's goal for reducing water use?

A: Not as well as hoped. Gov. Jerry Brown in January declared a drought emergency, and asked Californians to cut residential water use by 20 percent. The latest figures released Tuesday by the state show that Californians managed to reduce their daily water use by only 6.7 percent in October compared to the same period last year. The closest the state's 38 million people have come to meeting the 20 percent goal was in August, when water use was down 11.6 percent year-on-year. Still, the state Water Resources Control Board said Tuesday that Californians have saved 90 billion gallons since June — enough water for 1.2 million people for a year.

Q: Why are Californians falling so short?

A: Water board officials said they're trying to figure out if the usage was caused by a lack of awareness about the drought; not enough enforcement of conservation guidelines; this year's hotter weather; or something else. Board members threw out ideas Tuesday ranging from asking the state Transportation Department to post stronger messages about the drought on flashing highway advisory signs, to looking at whether more penalties should be imposed on big water users.

Water board officials say some of the key problem areas are affluent communities in Southern California, where rainfall is always short but residents love their green lawns, golf courses and swimming pools. Californians in the south coast region managed to cut water consumption by only 1.4 percent in October, the weakest showing in the state.

Q: It's raining in California now, so why still worry about saving water?

A: California officials say the state would need 150 percent of its normal annual rainfall to recover from drought. As of this autumn, the state had marked its driest three years on record, the federal government's National Climactic Data Center said. Storms so far this rainy season have brought parts of the state closer to normal rainfall for this point in the year. But the most important reservoirs contain just 39 percent to 60 percent of normal water levels. The snowpack in the Sierra Nevada, one of the most critical sources for state water year-round, is also lagging. Before the Tuesday storms, the southern Sierra had gotten just 47 percent of its normal rain and snow so far, and the northern Sierra 79 percent.

Q: How hard is the drought hitting California?

A: Poorer, rural communities in the agricultural Central Valley are feeling some of the sharpest impacts. Hundreds of wells have gone dry as water tables recede, leaving families to rely on trucked-in water or even water collected for them by Girl Scouts. Some farmers say they've had to spend thousands of dollars more to dig deeper well or buy water, and some have seen almond and pistachio trees or other orchards shrivel. The drought has been hard on wildlife as well. State and federal officials last month, for example, said low water in creeks meant one kind of coho salmon in Northern California was apparently unable to breed at all this year. The officials had to move all year-old cohos in that creek to a hatchery to try to save the species.