A giant East Rochester sinkhole has been turned into a pile of mud, and that's good news for businesses in Riverview Plaza and motorists on Ohio River Boulevard.

Workers from the state Department of Transportation recently capped a broken section of culvert at the bottom of the hole and back-filled it with enough dirt to stabilize the cap. PennDOT spokesman Jim Struzzi said the agency was now working with two private companies to re-establish the culvert's full drainage to the Ohio River.

That will end -- mostly, anyway -- the sinkhole's two-year run in the news, during which it forced the demolition of a restaurant and the reinforcement of a highway while spawning multiple lawsuits and a great deal of hand-wringing.

The sinkhole was caused by the failure of a vertical drain under the Evergreen Restaurant parking lot. Debris from that failure clogged the 12-foot culvert below. When the culvert backed up, it eroded the earth and created a sinkhole that eventually reached about 100 feet across and 60 feet deep.

The Evergreen was forced to close in September 2007 and the building was demolished four months later. Parking spaces were blocked off as the hole widened toward the neighboring Pizza Hut and Hollywood Video store. Meanwhile, runoff water was forcing its way under Ohio River Boulevard. Concerned about erosion, PennDOT this spring installed wire rock baskets to stabilize the ground.

A July storm, however, did what engineers had not been able: It opened a channel through the debris inside the culvert, relieving the pressure in the system. Until then, PennDOT engineers had been afraid to try to clean out the culvert from below. But with no threat of unleashing a pressurized torrent of mud and water, that became possible.

That brought repair estimates down from more than $1 million to roughly $80,000.

Mr. Struzzi said the work done to cap the broken culvert went well, but two downstream culverts -- one belonging to Norfolk Southern running under its railroad tracks and one belonging to Valvoline running under its industrial property -- need to be cleaned out first so water can run all the way through.

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