Pending approval from the City Council next week, Atlanta plans to refund more than $737,000 to 541 customers who were overbilled for water service.

Thirty-six of those customers will each receive more than $5,000, including two in one city district who will divide $46,632.

The refunds are the result of an audit of the city’s small meters in 2011, which reviewed nearly 160,000 water meters that were installed after 2006 with the aim of improving billing accuracy, identifying leaks and cutting the time it takes to read meters. Small meters primarily serve residential customers.

But that $35 million project didn’t go smoothly, and some Atlantans were shocked to see their water bills spike. One woman told The Atlanta Journal-Constitution that her bill climbed as high as $10,000, but no leaks were ever found.

The city’s Department of Watershed Management has made several changes as a result of the small meter audit. For one, the department is lowering the threshold that triggers a meter investigation from usage exceeding 100 percent of the monthly average to 50 percent of normal use.

“We hope this will establish confidence not just in (our) meters, but in our staff,” Watershed Commissioner Jo Ann Macrina said. “And we know there is still room for improvement.”

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