A DeKalb County homeowner is upset about a $1,500 water bill he received, and he’s also upset that he can’t get an explanation.

Brian Hammer, a Georgia Tech biology professor, lives in Decatur Heights. Hammer told Channel 2’s Linda Stouffer he has a 20,000 gallon pool, but can’t explain 120,000 gallons of water use on his county water bill.

“The amount was $1,545.10. We got this enormous spike so I go crazy and start plotting data, because that’s what I do,” Hammer said.

Hammer told Stouffer he filled an 18-gallon tub and recorded the meter reading and found it to be correct. Then he started calculating water usage for his sprinkler system, calculating how many gallons came out of each sprinkler head on average.

“So you knew you didn’t have a leak?” asked Stouffer.

“I knew I didn’t have a leak in the entire system,” Hammer said.

When Hammer took his charts to the DeKalb Department of Watershed Management to prove there was a problem he found out that no one physically read his meter. Officials told Hammer the last physical reading came in April 2010 and the rest have been estimates. Those estimates were low, so the county sent a bill to make up the difference last month, Hammer said.

“The problem is a catch-up bill that’s enormous. You pay at the highest tier for your water usage, Tier 4, which is quadruple the price of Tier 1,” Hammer said. “They don’t say anywhere on the bill this is not a real reading, in fact they say the opposite.”

DeKalb County officials told Stouffer they are looking into the billing issue.

Hammer said he sent a warning to neighbors and learned several others received a water bill over $1,000.