State water officials on Wednesday softened their approach to telling thousands of California farmers to stop pumping from rivers to irrigate crops during the drought but warned that stiff penalties still await anybody who takes water they don't have a right to use.

The state changed its tack just days after a Sacramento County judge sided with an irrigation district that challenged previous curtailment notices, saying the letters amounted to an unconstitutional command to stop pumping.

Superior Court Judge Shelleyanne Chang indicated the State Water Resources Control Board can only advise water rights holders to curtail use and fine them if the agency determines use exceeded the limit.

David Rose, an attorney for the water board, said the revised notice to farmers amounts to an advisory that river levels are critically low and there is not enough water, even for those who hold some of the strongest rights.

"The facts underlying the notice remain true and perhaps even more so as time has passed because it's only drier," Rose said.

Farmers shouldn't be surprised if they receive stiff penalties for using water they don't have the right to pump, he said.

Attorney Steven Herum, who represents the West Side Irrigation District in the case challenging the previous notices, said the ruling on Friday amounted to vindication.

Farmers had stopped directly pumping river water and are now considering if they will resume in light of the ruling, he said.

In recent months, the water board sent curtailment notices to 4,600 farmers and other water users. Farmers were told to stop irrigating fields as the state struggles through its fourth year of the drought.

The letters noted that anyone who illegally takes water could face fines of $1,000 a day or $2,500 per acre-foot of water.

Also on Wednesday, state officials approved stringent water limits on landscapes for new homes and businesses to further California's push for water-conscious development.

The new rules approved by the California Water Commission would essentially eliminate grass from future office and commercial buildings and reduce turf at new homes from a third of landscaped area to a quarter.

In order to comply, developers would have to install drought-tolerant features such as rocks, shrubs or cacti, or have irrigation systems that use water recycled from drains and home appliances instead of drinking-quality water.

Homeowner's won't have to rip out existing lawns unless they're going through major renovation requiring government permits.