The state Supreme Court has cleared the way for Southern California’s powerful Metropolitan Water District to buy five islands at the epicenter of the delta’s water system, officials said Friday.

Some officials and environmentalists in Northern California had fought to halt the sale, worried about what the MWD planned to do with the land. The agency has said it might use some of the land to provide access for the construction of a proposed delta tunnel system, a controversial project some oppose amid California’s five-year drought.