The city budget has taken a half-million dollar hit so far this year as water usage has dried up in the face of cool, wet weather.

Ed Mullins, the city’s finance director, said Monday that water sales dipped to $6 million this year from $6.5 million at the same time a year ago.

“We’re kind of due for a bad one,” Mullins said. “The good years offset the bad years.”

By Sunday, a total of 38.17 inches of rain had fallen this year at Lawrence Municipal Airport, where the city’s official rainfall total is recorded. Average annual rainfall in Lawrence is 39.79 inches.

The heavy rainfall led to an 11 percent decline in water usage across the city, officials said last week. But they’re not worried — the water utility has roughly $15 million in reserve funds for future capital improvement projects, which are readily available to shore up any shortfall in the system’s revenues.

The money is saved, Mullins said, so the city won’t have to go into debt to finance water-related construction projects. The last water-related bonds issued by City Hall, he said, were in 1997.

And those savings also help the city through down years in water sales.

“We’ve got a pretty good fudge factor in there,” Mullins said.