SAN DIEGO -- The San Diego City Council voted Tuesday to approve a 7.75 percent water rate increase.

Starting Jan. 1, a water bill for a typical single-family home in San Diego will increase by $4.73 a month to $65.76, according to a report from the Water Department.

It will be the sixth rate hike since 2007.

Jim Barrett, director of the Water Department, told the City Council the increase is needed to offset the higher cost of imported water from the San Diego County Water Authority.

"This is driven specifically by an increase at the County Water Authority," he testified.

The City Council voted 5-2 to approve the rate increase. Council members Donna Frye and Carl DeMaio cast the dissenting votes, and Council President Ben Hueso was absent.

DeMaio said it was the wrong time to raise water rates.

"San Diego working families are having a hard enough time right now as it is with this economy making ends meet," DeMaio said. "For us to add to their troubles during this economic downturn with yet another water increase is not something I think is appropriate or doable for them."

About 14,000 protests against the water rate increase were received by the San Diego City Clerk's Office. Had more than half of San Diego's 270,000 water customers returned a form protesting the increase, it would have been rejected under provisions outlined in Proposition 218.