The shaft opening was secured with a steel plate Monday night, after a day of exploration that included lowering a small video camera into the shaft to determine its depth and past usage.

Residents in the residential area east of Woodinville called in the problem on Friday evening. King County responded quickly to place barricades and a temporary cover on the 3-foot wide hole in the roadway. Roads crews kept an eye on the hole over the weekend, but it did not widen at the surface.

A larger crew responded Monday morning and initial measurements led them to believe that the shaft was as deep as 1,000 feet. But later, the video camera indicated the shaft may only be 236 feet deep.

Crews say the shaft appears to have been drilled at some time in the past, and does not appear to open up to a wider void underneath the surface of the road. There is also a thin pipe of six-inches or less in diameter that runs down the entire length of the shaft.

Since the first videotaping did not conclusively reveal the purpose of the shaft and pipe -- for example, whether it is an abandoned water well -- the county is now considering using a much smaller camera that could be lowered through the pipe. The county must first determine if the pipe conveyed water, oil, or other underground materials before a course of action can be developed.

See what's below in new video taken by a camera sent down the shaft by GELCO Services of Auburn. The numbers onscreen mark the number of feet below street level. [96 seconds, requires free RealOne player.  The video pauses 31 seconds into the clip, then continues.]


[enlarged view]

The hole in the road is not wide....

[enlarged view]

... but the shaft below is several hundred feet deep.