San Diego water officials were dealt a major legal loss Wednesday that could leave local water customers on the hook for billions of dollars over the next several decades. For years, San Diego water officials have argued that the region’s major supplier of water, the Metropolitan Water District of Southern California, has been charging too much to deliver water to San Diego from the Colorado River. But on Wednesday, an appellate court found that San Diego water customers are, by and large, only being asked to pay their fair share to use a statewide water delivery system.

The next time San Diegans face a proposed water rate increase, the City Council will be getting a second professional opinion about whether the increase is necessary and how large it should be. The change comes after the city approved in late 2015 a series of rate increases totaling nearly 40 percent over four years, including a 6.4 percent hike that will take effect July 1.

A legal ruling that San Diego County water officials said would save customers here up to $7 billion has been overturned. A California appellate court on Wednesday partially reversed a 2015 trial court ruling that awarded the San Diego County Water Authority $234 million in alleged overcharges, interest and legal fees to be paid by longtime legal foes at the Los Angeles-based regional agency known as MWD, or the Metropolitan Water District of Southern California.