May 4, 2005

Pressure causes manhole covers to blow

Closes Meridian Avenue to car, foot traffic

By Carol Rosen
Editor

Popping manhole covers caused the fire department to close Meridian Avenue between Fruitdale and Minnesota to cars and pedestrians on May 1 from about noon to 5:30 p.m.

Firefighters at Willow and Meridian on Sunday, May 1 seek to determine what substance is causing the pressure to pop manhole covers.

Four manhole covers popped off and moved about a foot, said Capt. Allison Cabral, public information officer for the fire department. San Jose Deputy Chief/Fire Marshall Dave Schoonover told the Times there were reports a cover had hit a car, but those could not be substantiated and no injuries were reported.

The covers blew off between Willow and Fruitdale and there was a strong smell of some type of gas moving toward Willow. Hazardous material teams from San Jose and Santa Clara were inspecting the sanitation lines to determine what was causing the pressure.

However, the closest anyone could determine was that some type of hydrocarbon was in the sanitation line, but they could not determine what exactly it was or where it came from. They flushed the line with Class A foam, which is a surfactant (like dishwashing detergent) that dispels any possibility of the gases elevating to a dangerous level.

Also on the scene were a number of police officers directing traffic away from the area, and Pacific Gas and Electric. Very few pedestrians were out and any traffic in the area—at coffee shops, for example—were directed to leave around 2 p.m.

This isn’t the first time popping manhole covers have closed Meridian Avenue. Several years ago, firefighters determined someone had spilled a hydrocarbon substance down the sewer line, but the who and why were never determined.