California officials don’t have to pay property owners to access their land to conduct preliminary testing before deciding whether to move forward with a $15.7 billion plan to build two giant water tunnels to supply drinking water for cities and irrigation for farmers, the California Supreme Court ruled Thursday.

The landowners in the Sacramento-San Joaquin Delta had demanded payment for thousands of acres sought by the state for testing. The payments would have added millions of dollars to the cost of the tunnels project.

State officials said being forced to rent the land for testing would have also set a dangerous, expensive precedent regarding other public works projects.

The state Supreme Court ruled 7-0 in the state’s favor, giving Gov. Jerry Brown a major victory in his fight to build the tunnels.

Rental fees for the land were not necessary because the state is seeking temporary access, and land owners would be able to recover money for any damage or interference the testing caused, Chief Justice Tani Cantil-Sakauye wrote.

Ted Thomas, a spokesman for the state Department of Water Resources, said the ruling validated the procedures being used by the agency.

“We will continue moving forward with our important work to modernize California’s water infrastructure to better protect the delta ecosystem and water supplies,” he said in a statement.

Property owners said the tests will be lengthy and invasive and constitute an occupation of their property.

Norman Matteoni, an attorney for one of the landowners, said the landowners will consider whether to appeal the case to the U.S. Supreme Court.

Tom Keeling, another attorney for landowners, predicted the ruling would make landowners “more vulnerable to aggressive tactics” by the state.

The tunnels project would run twin, four-story pipes underground for 35 miles and eventually pull thousands of gallons of water a second from a stretch of the Sacramento River to send to cities and farms to the south.

Supporters say the project would ensure a more reliable water supply and protect fish species. Opponents contend it would jeopardize delta farming and destroy vital wildlife habitat.

Officials promoting the tunnels will present plans to state water regulators in hearings starting Tuesday. The State Water Resources Control Board will decide whether tunnel backers have a right to take water from the river near Sacramento — a major hurdle for the project to move forward.

The testing at issue in Thursday’s ruling involves access to about 150 properties covering tens of thousands of acres in San Joaquin, Contra Costa, Solano, Sacramento and Yolo counties.

The environmental testing includes trapping wild animals and taking soil samples. For geological testing, experts would bore holes up to 8 inches in diameter and 205 feet into the ground. The holes would be filled after the testing is completed.

Attorneys for landowner Property Reserve Inc. said in court documents that the preliminary project work would destroy crops and disrupt fertilizer and pesticide use.

An appeals court in a 2-1 ruling two years ago sided with property owners, saying the testing constituted “taking” of private property. That court said that under California’s state constitution, the property owners were entitled to a determination of the market value of the property rights the state was acquiring for the project.