BURIEN, Wash. -- Neighbors under the flight path of Sea-Tac Airport's third runway knew the day would come when the 16-year project was completed, as occurred last Thursday.

But they say they are seeing way more planes use that runway than they ever expected.

"(The noise) is kind of obnoxious," said Brian McClurg, who lives under the flight path. "It's like your neighbor's dog barking all the time."

"I didn't realize the sound was going to be such an effect," added Janelle Dempsey.

And it's not just the noise...

"(I) don't want to get anymore jet fuel on my 5th wheel," Earl Fahrney said. "It's hard to clean it off."

Neighbors say since the third runway opened, the planes have just flooded in as if it was the main runway. All along, neighbors thought the new runway was going to be a secondary option, used only during bad weather or during peak travel times.

But they say the third runway landings have been nearly non-stop, even through the weather has been great. And the old runway, which they've lived with for years, has been used only sparingly.

"We've been told it's for overflow; it's not a constant, primary runway," said neighbor Andrea Maki. "They've reneged already."

Sea-Tac Airport's Web site states: "In general, the third runway won't be needed as often in good weather."

But Sea-Tac doesn't control its own runways. The FAA decides if runway 16-Right, the third runway, is needed.

"If the observations are correct of 16 Right was used more than 16 Left, I don't have an answer for that right now," said Mike Fergus with the FAA. "But that's an exception of what the policy is."

Fahrney says the runway hasn't been used for take-offs yet.

"Nope, they haven't taken off yet and I'm going to regret that day."

Neighbors have put up signs to encourage calls to the airport's noise hotline. For Janelle Dempsey, the noisy reality has brought her to tears.

"Do we sell, do we stay? Do we stick it out? We'll just have to see. You just don't realize it until it's here."

Sea-Tac says it has logged about 90 complaints since the weekend. Normally, they'll get about four or five.

The FAA says it is meeting to review how they are currently using the new runway.