Manhold cover explosions - for the archives : LUSENET : Grassroots Information Coordination Center (GICC) : One Thread

GICC has received the following postings and clips on the manhole cover explosions and potentially related phenomena - for the archives

OHIO - Fire in Electrical Cables Under Street, Blasts Pop Manhole Covers : LUSENET : Grassroots Information Coordination Center (GICC)

[Fair use for education and research purpose only]

Title: Blasts Pop Manhole Covers

April 17, 2000


A fire in electrical cables underneath Huron Street downtown caused explosions that witnesses said blew two 350-pound manhole covers as high as 20 feet in the air and tore up a 10-foot-diameter circle of pavement late Sunday afternoon.

About a dozen people who were in the Ameritech building, 121 North Huron St., complained of scratchy throats and watery eyes from smoke that got into the building.

Some took oxygen from paramedics but declined to be examined at a hospital, said Lt. Ken Kantura, safety officer with the Toledo fire department.

The problem started with a short in the secondary electrical cable lines that are in a utility tunnel beneath Huron between Jefferson Avenue and Monroe Street.

The cable, which is 45 to 50 years old, is covered with lead, and when it burned, it created gas that fueled the explosions, said Jerry Goeckerman, a Toledo Edison foreman.

One explosion occurred in front of the Ameritech building; the other was farther north on Huron.

Toledo Edison Co. crews were expected to work through much of the night on the cables, with little or no disruption to electrical customers.

The three-lane street is expected to be open this morning with barrels around the torn-up pavement, Mr. Goeckerman said.

The explosions started shortly before 6 p.m., just as a demolition crew with C.S. Burge, Inc., was preparing to leave the building it was taking down in the 600 block of Jefferson near Huron. Fire officials last night said they did not know of a link between the demolition and the explosions, but were investigating.

Vice President Chuck Burge said he was packing up his things when he heard a loud bang. His wife told him she believed someone had just hit one of his huge trash receptacles by the Street.

When he went to look, however, he said he saw a blue flame in front of the Ameritech building.

Jim Bennett, an equipment operator for C.S. Burge, was stepping off a crane when he saw a manhole cover fly about 20 feet into the air. He said he saw two explosions and heard three. He called 911 from his cell phone.

The first help to arrive, however, was Dale Williamson, a city traffic signal technician who said he got a call from his dispatcher, asking him to place a barrel over a manhole cover.

When he arrived, he said, he saw green and orange flames that appeared to be 25 feet high for an instant, blowing off the second manhole cover. He said he smelled gas.

"It was like a boom, an explosion," Mr. Williamson said.

James Preston was talking on the telephone on a top floor of the Commodore Perry Apartments when he saw a manhole cover shoot 20 to 25 feet into the air, higher than the arches on the Ameritech building.

The friend to whom he was talking heard the explosion as well. Mr. Preston, a Coca-Cola account manager, described the smoke that he saw streaming from the manholes as light green, then dark green. Later, it became dark brown.

The fire department called Columbia Gas and Ameritech representatives to the scene to determine the cause of the explosion. Just after 6 p.m., firefighters were warning bystanders a block away to stay away from manhole covers. But shortly after 7 p.m., Lieutenant Kantura certified that the fire appeared to be out.

Fire officials tested the air in the Commodore Perry parking garage and other areas where people said they smelled odors and found it safe, he said.



Electrical Explosion Shuts Down Montreal Subway : LUSENET : Grassroots Information Coordination Center (GICC)

Apr 15, 2000 - 11:16 AM

Electrical Explosion Shuts Down Montreal Subway The Associated Press

MONTREAL (AP) - An explosion apparently sparked by an electrical problem shut down Montreal's subway system Saturday morning, a transit official said. No injuries were reported. The blast and a subsequent fire knocked out the subway communication system, and yellow smoke that billowed out of two manholes caused authorities to evacuate about 100 people from their homes in case the smoke was toxic.

"We're fortunate that this happened on a Saturday morning," when traffic was light, said transit spokeswoman Odile Paradis.

She said no train passengers were injured in the explosion at 7:45 the Laurier subway station in central Montreal. Scores of buses were deployed throughout the city to transport people waiting for trains. Paradis said she expected the subway system to be operating as usual by Monday.

-- Carl Jenkins (, April 15, 2000


Canoe Saturday, Apr. 15, 2000 Several thousand forced from Montreal subways

By ALEXANDER PANETTA -- The Canadian Press

MONTREAL (CP) -- Several thousand people were forced from the subway system on Saturday after an underground fire and a series of small explosions.

The blasts at 7:45 a.m. shut down the entire system -- 65 stations -- for about six hours. Limited service was restored by mid-afternoon.

There were no injuries reported -- either to passengers on trains or residents in the area of the blasts.

"We're fortunate that this happened on a Saturday" and not during the work week, said transit spokeswoman Odile Paradis.

Paradis said sunny, mild weather also helped to ease a potential transit nightmare because many people preferred to walk rather than use public transportation for short trips.

Subway trains and stations had to be evacuated.

"I have a math test -- and I'm already late," said Lloyd Pierre-Louis, waiting for a bus outside the mid-town Laurier station.

Pierre-Louis had been forced to take another bus into town, instead of the subway, from his home south of the city.

He thought he was 45 minutes late for a final exam at the Ecole Polytechnique but school officials, aware of the problem, had postponed the test for one hour.

Paradis said the evacuation was performed calmly, adding there were no problems with passengers.

The fire and explosions happened near the Laurier station, in Montreal's trendy Plateau Mount Royal district. The fire was confined to two manholes near the station.

The damage knocked out the entire line's communications system and killed contact with train drivers, forcing a full evacuation and shutdown.

The cause may have been an underground cable that had already been damaged by a recent house fire in the area, said Yves Boucher, a city spokesman.

But one fire official said a power surge might have been the culprit. "There was a lot of smoke and at least two gas explosions," said fire marshal Ron Dubeau. "When insulation and wiring catch fire, the burning plastic causes toxic fumes that explode when there's not enough air."

The blasts and fire also disrupted power to several thousand residents near the station and about 200 homes were still without electricity by 5 p.m.

More than 100 people were also forced from their nearby homes by thick yellow smoke, which smelled like burned plastic, that billowed from the manhole covers.

Only small traces of the damage remained by mid-afternoon.

A halo of charred concrete surrounded the manhole cover where the fire began and barricades blocked one sidewalk corner of the nearby intersection, where traffic lights were still out.

About 250,000 commuters use the subway system on a typical Saturday, Paradis said.

More than 100 extra buses were put on the road to keep people moving.

The buses were crammed with passengers, although one area merchant said they arrived frequently and there were no long lineups.

"It's actually quiet for a Saturday -- there'd be a lot more people here if the subway were running," said Youssef Essoulami, who owns a coffee shop on St-Denis Street, a popular thoroughfare lined with caffes and sidewalk patios.

Paradis said Saturday was only the third time the whole subway system had been knocked out of service, the last time being during the ice storm in 1998.

She said she expected full service to return to normal by Monday at the latest.

A collision of two subway trains in Toronto in 1995 during afternoon rush hour killed three people and injured 36 others.

Two key causes of the Toronto crash were a mechanical problem and an inexperienced driver. ******************************************************************************* Attachment 2 - Montreal

1) Update Montreal subway explosions : LUSENET : Grassroots Information Coordination Center (GICC)

Explosion in a manhole? Hmmmm seems I have seen that before.

Sunday 16 April 2000

Metro knocked out

Transit chaos for thousands as electric fire closes subway NICOLAS VAN PRAET and INGRID PHANEUF, DARREN BECKER of The Gazette contributed to this report The Gazette

Transit users in Montreal were forced to cope yesterday with the biggest subway stoppage the city has ever experienced - a six-hour paralysis caused by a electric fire in a manhole.

People who normally travel below-ground spilled onto the sidewalks. For a city second only to New York in percentage of residents who use the transit system, the impact was enormous.

More than 200,000 metro-users were herded onto 150 backup buses or obliged to find other transportation starting about 8 a.m., after an explosion in an underground electric-cable chamber knocked out the communication and ventilation systems in all 65 stations.

That means users would not have been able to breathe fresh air in the subway tunnels and metro drivers would have had no way to communicate. The green and red lights indicating safe passage through the tunnels also lost power.

No one was injured.

'Should Never Happen'

"This is an unforeseeable event that should never happen," said Montreal Urban Community Transit Corp. spokesman Odile Paradis.

"People were crowded and delayed for sure. We saw today just how essential the subway service is." Her words were little consolation for those who count on the metro to get where they need to go on time.

"I'm trying to get to the Jewish General (Hospital) with my kids," Elaine Stewart said outside the Parc metro station at the corner of Jean Talon and Hutchison Sts. in Park Extension.

"I had to walk here from the Acadie metro station, and now I'm going to have to take a shuttle bus. We're supposed to be there by 1:30 p.m."

It was 12:30 p.m., and Stewart still had a long way to go. Still, it was warm, sunny and Saturday. What could have been a nasty weekday rush-hour crowd was actually a ticked-off-but-not-angry-beyond-belief lot.

"We'll walk, that's all," said Yamina Bennai, who was taking her 6-year-old and 2-year-old to the movies downtown from the Laurier metro station.

"The kids are young but they'll survive."

Partial metro service was restored by mid-afternoon. But service to all of the blue line and to the orange line between Berri-UQAM and Henri Bourassa stations wasn't expected to be restored until this morning, Paradis said.

Taxi-drivers relished the rush of unexpected fares, taking full advantage of a shut-down subway system.

"I was supposed to be sleeping today," said cabbie Rejean Mauzerolle, who quickly canceled his plans to take a day off when he saw masses of people waiting outside metro stations.

"Normally I don't work weekends because I have three kids. But people are looking to us for transportation."

The fire started about 7:45 a.m. in an underground tunnel on the northwest corner of St. Joseph Blvd. and St. Denis St.

Inside the tunnel were 12- and 25-kilovolt high-tension cables for the MUCTC, Hydro-Quebec,Videotron and AT&T, said Yves Boucher of the city's electric service commission.

Fire burned through the plastic and rubber that coated the cables, emitting toxic smoke. A series of small explosions occurred. As yellow smoke billowed out, the pressure was enough to blow the manhole lid high into the air. About 100 people were led from their homes to safety.

"I saw one manhole cover on the northeast corner of St. Joseph Blvd. and St. Denis St. blow up as high as the two-storey office building next to it," MUCTC security agent Pierre Cardinal said.

Cardinal was on duty at St. Joseph and St. Denis when the explosion occurred.

"I parked next to the manhole to call the fire department and MUCTC headquarters when I saw the smoke coming up. I got a bit of a shock when the explosion happened."

Cardinal said two adjacent manhole covers along St. Denis also blew off, but not as high as the one he was parked beside .

After Hydro-Quebec shut off power through the tunnel, firefighters flooded the manhole with water. They filled another nearby manhole with foam. Workers then began pumping out the water. An orange tube filtered out any remaining gases.

Power to 4,000 homes was lost immediately, said Hydro-Quebec spokesman Jean-Claude Lefebvre. By noon, 2,500 still had no electricity.

Forty apartments were expected to remain without power last night as repair work continued, Lefebvre said. Yesterday's disruption was only the third time the entire subway system has been shut, Paradis said. The last time was during the 1998 ice storm.

Electrical fires as big as this one don't happen very often, Hydro-Quebec's Lefebvre said. "But statistically, no mechanisms are perfect."

The Montreal fire department is investigating the cause of the fire.

Boucher said an underground cable already damaged during a recent house fire in the area might have been the culprit. A power surge is another possibility, a fire official said.


Attachment 4

Man Hole Fires : LUSENET : Grassroots Information Coordination Center (GICC)

April 3 2000~ Man holes Fires in SanFrancisco creates Trafic havoc. Unknown cause. Anyone have any MORE INFO~~ Geno

-- Gene Snyder (, April 05, 2000


Try checking on the exploding manhole stories from Georgetown DC area @ new years - their story was road salt for snow draining into manholes and getting on copper and exploding - remember one board pundit trying to pour salt on a penny and nothing happened. Guess the best question is,do you use a lot of road salt in SF? If not maybe the symptoms are the same and the road salt explanation was off a little...

-- Patter is full (, April 05, 2000.

it happened in boston too

-- n (n@n.n), April 05, 2000.

The salt in question lowered the freezing point of the ice/snow as it was supposed to. However, when dissolved in water solution , it can attack the cables carrying the electricity (probably for years) and then when in contact with copper cable , would make a beautiful conducting solution between those cables and ANY metal that would ground it. Also, depending on the type of metals involved , hydrogen gas could have formed , until the oxygen/hydrogen gases reached the correct chemical combination of two parts hydrogen, one part oxygen ; then all you need is a spark/open flame to form water PLUS lots of heat and light .... like in an explosion ( technically known as an exothermic reaction) ; i.e. one that gives off LOTS of HEAT!! Eagle

-- Hal Walker (, April 05, 2000.

So this is a recurring thing in history as opposed to SCADA related...? -- I.B. Edumacated (, April 05, 2000.

Roger, understand. Giving this dreadful explanation and credence it can muster, how many years of salted snowfallen roads in San Francisco would it take for this to happen - and still fit in with Boston and Georgetown weather patterns? Their manholes should have blown up years ago rather than at the same year that SF did. It is interesting that they all never occurred before and did happen after Y2K...

-- Pattern is full (, April 05, 2000.

I.B., What is SCADA, please?

-- Margo (, April 05, 2000.

Supervisory Control and Data Acquistion

-- I.B. Edumacated (, April 05, 2000.

Local news provided by: Metro Networks

Streets Back To Normal It should be business as usual this morning on Mason and O'Farrell streets near San Francisco's Union Square. But that wasn't the case yesterday morning as fire broke out in an underground Pacific Gas and Electric transformer vault. Smoke could be seen, but the flames were underground making it tough for firefighters. Investigators say the blaze was probably caused by a short circuit. The biggest danger came from underground explosions that blew out manhole covers. Luckily, nobody was injured.

SAN FRANCISCO provider=metronetworks&category=News&article=443519

- Martin Thompson (, April 05, 2000.


NY - Schenectady Power Outage, Cable Shorted; Blows Manhole Cover : LUSENET : Grassroots Information Coordination Center (GICC)

Fair Use: For Educational and Research Purposes Only

Schenectady Homes Lose Power after Cable Failure

Source: Times Union Albany, NY

Publication date: 2000-05-17

SCHENECTADY -- A large section of the city was without power for about an hour late Tuesday afternoon when an underground cable shorted, blowing off a manhole cover, officials said. The power outage also affected traffic lights along the Crosstown, tying up traffic as people tried to creep through the intersections with Watt Street, Albany Street and Consaul Road. Niagara Mohawk Power Corp. spokesman Nick Lyman estimated about 4,000 customers lost power at 3:43 p.m. Crews were able to reroute circuits and power was restored at 4:42 p.m. 569740&site=charlotte&ID=realcities&scategory=Computers%3AY2K _________________________________________________________________

Attachment 6

From the Grassroot Information Coordination Center (unedited)

VERMONT - Power Grid Needs Emergency Repair Job : LUSENET : Grassroots Information Coordination Center (GICC)

[Fair use for education and research purpose only]

April 16, 2000

HEADLINE: Power Grid Needs Emergency Repair Job Failure Leaves Chittenden Co. Vulnerable

By JOHN DILLON Staff Writer

The electric transmission network that serves Chittenden County needs a multimillion-dollar emergency repair job that could require a new power plant to be installed temporarily in northwestern Vermont, utility officials say.

The Vermont Electric Power Co., which operates the state's high voltage transmission system, is asking utility regulators for emergency approval to install new lines, a large transformer and a new power plant in order to bolster the regional power system after a key piece of equipment failed March 22.

The equipment that failed - called a phase angle regulator - is located in Plattsburgh, N.Y., and controls the amount of electricity that flows over a high voltage line connecting New York and Vermont under Lake Champlain near the Sand Bar State Park. Without the phase angle regulator in operation, the line itself could fail this summer when electricity demand increases, leaving Burlington vulnerable to blackouts, utility officials worry.

Electricity, like water, flows along paths of least resistance, according to where it is being generated and where it is being used. The regulator that failed "actually forces power to take a particular path. Its function is the keep the line across the lake from getting overloaded," said Thomas Wies, VELCO's general counsel. "If lines are overloaded, they'll burn up. The PAV (phase angle regulator) is a device to prevent that from happening."

Repairing or replacing the PAV could take up to a year. But VELCO officials worry that when demand for power increases this summer, the power line under Lake Champlain would become dangerously stressed.

So VELCO engineers have scrambled to come up with several potential solutions that would essentially keep the power network in balance and prevent the Lake Champlain line from becoming overloaded.

If the line did become overloaded this summer, operators would be forced to shut it down, which then would leave the region susceptible to blackouts, said Public Service Commissioner Richard Sedano, whose department represents consumers in utility cases.

"To avoid (line overload), they would open the switch so the line would no longer carry electricity. That would create problems because it would reduce the amount of electricity flowing into Chittenden County. It would leave Chittenden County more vulnerable than we would like to see," he said.

Sedano described the situation as a "slow moving" emergency, one that will get more severe as electricity use increases in late spring and summer.

"There is a significant amount of exposure. VELCO is doing what it can to minimize what it needs to address it, but there could be some significant proposals that they're going to ask to be installed relatively quickly," he said.

The repairs under consideration are designed both to keep the Lake Champlain line in operation, and to bring in alternative electricity supplies should operators be forced to shut the line down, according to documents filed with the Public Service Board.

VELCO wants approval to build a 115 kilovolt transmission line from its Irasburg substation to the CitizensUtilities network, new connections between Citizens Utilities' lines and Hydro-Quebec circuits at Highgate, and a large, new transformer in West Rutland.

VELCO is also considering installing a diesel power plant near its Sand Bar substation in Milton in order to produce 35 to 40 megawatts needed to strengthen the system, Wies said.

The company is seeking emergency authority for the work in order to get some of the improvements in placebefore hotter weather hits and power demand increases. The emergency waiver would allow VELCO to bypass the detailed environmental and cost review required for major power projects. Wies said if VELCO is given the emergency waiver, it would undergo full PSB review later in order to make all the repairs permanent, except for the proposed Milton power plant. "The additional generation is something we would not ask to make permanent," he said.

VELCO also is reviewing state air quality regulations that could affect the power plant proposal, he said. "I don't know that even if the (PSB) thought it was a good idea whether we'd do it."

Small, portable power plants are not that easy to find. And the ones that are available are usually for sale, not for rent.

"These are not off-the-shelf items," Wies said. "We have a line on several possibilities, but we haven't signed any contracts. We're pretty sure something is available."

VELCO has not pinned down the cost of the various proposals, but the work will not be cheap. The phase angle regulator costs several million dollars. The upgrades to bolster the connections with the Citizens Utilities' system will also cost $2 million to $3 million, Wies said.

The question of who pays for the work has also not been answered, and depends in part on which improvements are made, he said. The cost of repairs to the New England transmission system are usually covered by all the utilities in the system, he said.

Wies said the work VELCO wants to do now under the emergency waiver is not part of a transmission upgrade the company considered several years ago as part of a plan to bring more power south from Hydro-Quebec. He said that project would have been valuable today because it would have made the transmission network more robust. "If we had it, it wouldn't be necessary to propose any of the actions in this petition," he said.

The goal of the emergency work this spring is to build reliability back into the system, he said. "It's a question of being prudently prepared for the summer. If nothing else happens, we should get through it OK. But the way you want to run a transmission system is to be prepared for the next worst thing that can happen."


-- (, April 16, 2000


What is a phase angle regulator?

What has failed on this job that dictates replacement rather than repair?

Is there a control problem involved?

-- Tom Beckner (, April 18, 2000.

End of forwarded material


-- GICC Sysop (, July 18, 2000

Moderation questions? read the FAQ