Diners in California take note. If your server does not fill your water glass, it’s because he’s forgetful—he’s just following the law.

Tuesday, Governor Jerry Brown passed new mandatory water conservation rules that will affect millions in the state, from single family homeowners to big businesses like restaurants and hotels.

"Originally, we poured water from a pitcher into bigger glasses," Hanna Mityashina, manager of Delicious Crepes Bistro in Santa Clara, told San Jose Mercury News. "We noticed when we reduced the size of the glasses, it reduces the consumption. We want to preserve water."

Though the new water conservation rules will take effect April 15, Mityashina is one of several restaurant owners that have reportedly started limiting water for customers.

"There have been some heroic efforts that people have taken, but we are not seeing the efforts to step up and ring the alarm bells that the situation warrants," Felicia Marcus, chairwoman of the State Water Resources Control Board, told the Mercury News. "We're going to need to go further if it doesn't rain."

Here's a look at how the regulations will affect California residents and businesses:

Restaurants

Servers in bars, restaurants and cafeterias can't bring out water with menus and silverware unless customers ask. Some restaurants already have signs saying they don't automatically serve water because of the drought. The rule is meant to raise conservation awareness more than save water.

Hotels

Hotel guests must get a chance to decline fresh towels and sheets. Business operators must place signs in the bathroom reminding them they have this opportunity to conserve.

Homeowners and landscaping

Local water departments have to limit how many days a week people water their lawns. The state standard is twice a week. Homeowners are also barred from turning on sprinklers on days when it rains and for the next two days after.

If an establishment or individual is found in violation of the rules, they will be subject to a fine of up to $500 per day—but enforcement throughout the state varies. Though local water departments must start reporting how they ensure their customers follow the water rules, very few residents have received fines for wasting water. This is likely to change as the rules become seriously enforced.

The Associated Press contributed to this report.