The 99-year-old northwest Washington woman insists it must be a mistake. Usually, her water bill is $30. In March, she did a double take.

"I got my usual bill and opened the envelope and looked at the amount," she said. "Huh? I looked again."

It was $1,181.

Cohen complained and had plumbers check her house twice. Usually, she uses about 3,000 gallons of water per month. D.C. Water and Sewer Authority's records show that 139,876 gallons went into her house that month, and they insist she must pay for them.

"It's just so obvious that, as the plumber said, 'You couldn't use that much water,'" she told News4's Tom Sherwood.

Ellen Cohen is worried about the stress this could cause her mother in law. Jeannette Cohen has lived in the same, modest house in the Tenley Circle area since 1955, and in December she turns 100.

"She would never dodge something that she owed, but she's also very fair and she has a real belief in justice," Ellen Cohen said.

Jeannette Cohen has a hearing scheduled for June 30.

"Well, I have hopes," she said. "I would love to have it fixed just because it is so stupid and so wrong."

WASA told News4 it reconfirmed its records but is concerned, too, and will investigate further.