A court ruling could mean a delay for Governor Jerry Brown's Delta Tunnel Project.

An appeals court says state water officials cannot go on to private property to conduct environmental studies related to construction of the two massive tunnels, unless they get permission, or use eminent domain.

"The investigations the state wanted to conduct consists of drilling activities," Stockton Attorney Tom Keeling said. 

They were also wanting to conduct biological sampling.

Keeling represents more than 90 landowners with thousands of acres and says this certainly doesn't end the project but it does slow it down.

"David can defeat Goliath, you just have to fight smarter," he said. 

The Department of Water Resources says they have contingency plans. There's no word yet on a state appeal.