Sacramento-area residents will pay higher sewer rates starting in October, as part of a series of rate hikes that will raise bills by 30 percent over three years.

The Sacramento Regional County Sanitation District approved the increases Wednesday. The district provides service to 400,000 customers in Sacramento County and West Sacramento.

For the average home, monthly rates will go up $2 to $22 this year, then increase by the same amount on July 1 of 2012 and 2013.

The increases are mainly intended to cover the costs of meeting a wastewater discharge permit approved by a state board in December, said Stan Dean, a district engineer.

The permit imposes new treatment requirements on the district. The state board that approved the permit found that discharges are degrading the food chain of the Sacramento-San Joaquin Delta, the largest estuary in the West.

"It is a very, very stringent permit," Dean told the district board Wednesday.

The district expects to spend $2 billion to construct new treatment processes at its Elk Grove plant, and an additional $77 million a year to operate and maintain them.

The three years of rate increases won't recover all of those costs, district officials said. The district will have to revisit the rates later, Dean said.

The board – made up of county and city officials from Sacramento and Yolo counties – voted 9-2 in favor of the increases. Sacramento County Supervisors Susan Peters and Roberta MacGlashan were opposed.

MacGlashan said the increases will create too much of a burden for some residents. Peters didn't return a call Wednesday seeking a comment about her vote.

The district anticipates it will need a total of 10 years of rate increases to pay for the capital improvements and higher operational costs.

Under the rate plan approved Wednesday, district officials estimate that rates will go from $20 a month now on average to $35 a month in 2015 and $62 a month in 2020. The district held off on approving rates for later years for a couple of reasons, Dean said.

The district has appealed the permit to the State Water Resources Control Board. While district officials expect they will have to make improvements regardless, they hope an appeal will result in some cost mitigation.

The district, with the help of Assemblyman Roger Dickinson, D-Sacramento, is trying to get a bill passed at the Legislature that would help the district sell treated wastewater. The revenue from the sales would help offset the costs of treatment.

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