Vivian Parker of Chevy Chase was shocked when she received an $850 bill from D.C.'s Water and Sewer Authority for the fall quarter. Not only did the unusually high charges bother her, but so did the amount of water she was told she had used: 178 units, nearly four times as much as the previous fall.

"This wasn't just higher," Parker said recently, "it was so out there, it couldn't be anything other than an error."

Ives Goddard knows the feeling. The Georgetown resident got a charge in November from the water and sewer agency, or WASA, for twice the usual amount. He inspected the charges and decided that WASA had mistakenly double-billed him.

"If it goes up exactly twice, something else is afoot," Goddard said. "When they switched to new meters, maybe the software was set up wrong."

Last week, The Washington Post reported on cases of unusually high water bills in various Northwest neighborhoods. WASA officials attributed the higher charges to new meters being installed throughout the city that more accurately measure water usage. About 80,000 of 125,000 residential meters have been installed, officials said, and the rest of the work is to be completed this year.

Many residents continue to insist that some of the bills result from faulty new meters or clerical errors stemming from the replacement project. Parker and Goddard said they received billing reductions after protesting their cases to WASA.

"They said I will receive a new bill within a week," said Parker, relieved that her bill was reduced but by no means certain that the problem had been fixed for the next billing cycle.

"I'm not at all confident," she said.

WASA began the $36 million meter replacement project last year, spokeswoman Libby Lawson said. In many cases, the old meters have been in operation for 25 years and were not functioning properly. The new, high-tech meters will take automatic readings instead of relying on meter readers and will also allow customers to be billed monthly, instead of quarterly.

WASA has received some complaints, Lawson acknowledged, but she said auditors have found relatively few errors. Statistics provided by the utility show that auditors have inspected 46,092 meters and found 594 billing problems caused by meter installation errors and an additional 180 problems linked to data and computer errors. That is an error rate of 1.7 percent.

"We have run into a very low percentage of actual installation errors," Lawson said. For such a significant project, she said, some errors "are expected, and when that occurs we try to correct it."

D.C. Council member Carol Schwartz (R-At Large), chairwoman of the Committee on Public Works and the Environment, announced last week that she will hold a public hearing about the new meters at 10 a.m. Feb. 5 at the Wilson Administration Building, at 1350 Pennsylvania Ave. Those who wish to testify should contact Jim Slattery by phone at 724-8105 or by e-mail at jim.slattery@dc.gov by Feb. 3.

The council is also considering legislation that would put WASA, which was established as an independent agency in 1996, under the purview of the Public Service Commission. Some council members support that move, saying that more government oversight is necessary. But WASA officials oppose the idea, saying it would result in higher fees for residents.

Comparing WASA to another utility, Lawson said: "Whenever Washington Gas goes before the Public Service Commission to present its case on a rate increase, the cost of the PSC and the Office of the People's Counsel is funded by those rates. We've done an analysis which shows our rates would be increased to support going before the commission."

Such logic is no solace for residents who are wondering about the large spikes in their water bills. Residents complain of long waits for an auditor to inspect the new meters after protests are logged. They also say that even when they get their bills reduced by telephone, they later receive statements charging them the original amount.

"It's so convoluted," said Jennifer Greenberger of Chevy Chase, who challenged her bill and was told it would be reduced but then received an even higher charge. "My impression is that you are not really getting charged for the water you use. It seems like they are just taking a shot in the dark."

Michael Johnson of Adams Morgan said he challenged his summer quarter bill of $253.33, which was far above his usual bill of about $70. After auditors failed to appear twice for promised appointments, he received a bill for $368.95, Johnson said.

But Lawson said that although some problems are inevitable during a major capital overhaul, most of the billing increases come from more accurate water usage readings by the new meters.

"Through direct communication with our customers and in public meetings, we informed the customers that we would take on the initiative to do this," Lawson said of the meter replacement project. "In trying to explain this to customers, we noted that the bills may be higher in making this change."