Clogged sewer line? Call a professional and 811

Clearing a clogged sewer line may seem to be a simple fix, but it’s important to call 811 and a professional plumber to ensure the clog is cleared properly and safely.

A call to 811 will help determine if your clogged line could be caused by another utility line crossing through the sewer line – a rare situation called a cross bore. Cross bores can pose a safety risk, if not addressed properly. Calling 811 won’t guarantee a sewer line is free from cross bores, but it will show you if there are utilities nearby.

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Your sewer line's backed up. Time to spring into action and fix it fast. Stop, take a minute to call 811 first. A Columbia Gas representative will mark the gas line on your property in two to three hours in most cases. A plumber can then use a camera to ensure that the line can be safely cleared. But you can't see everything, so if a gas line is marked near the clog, contact Columbia Gas immediately. These simple steps can prevent a serious safety risk to you and your family, even save lives. If you or your plumber tries to clear a blockage using a mechanical snake or root cutter, a gas line could be damaged. This can create a dangerous situation, potentially allowing natural gas to fill the sewer and back up into your home. All across the state, in both old and new neighborhoods, cross bores may have been unknowingly created in sewer lines. Cross bores occur where one underground utility crosses through another. Gas or other utility lines may be in sewer lines outside your home. Be safe. Before you act to mechanically clear a clogged drain, call 811 first. Protect your family, home and neighborhood.


Important safety precautions

If you are present when sewer lines are being cleared, be alert to any unusual conditions, which may include:

  • Hissing sounds
  • Natural gas odor (rotten egg smell)
  • Blowing dirt
  • Bubbling water (which could be seen in places with standing water such as a toilet or puddle)

If at any time you suspect a gas leak or that contact with a natural gas line has occurred:

Stop what you're doing

Stop what you’re doing

Don't smoke or light a match. Don't open the windows. Don’t use anything that could cause a spark, like a phone, light switch, appliance or flashlight. Don’t start your car or use your garage door to leave.

Leave the area

Leave the area immediately

If you're inside, get out immediately. If you're outside, leave the area quickly.

Call us and 911

Call 911 and us

From a safe location, away from the building, call 911 and our emergency number at 1-800-344-4077 and wait for crews to arrive.


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Common questions

How do cross bores happen?

Many utilities try to minimize digging in yards, sidewalks and driveways when installing underground pipelines and cables. The technology they use allows for safe and efficient construction in existing neighborhoods and urban areas but can lead to cross bores when a line inadvertently intersects underground facilities.

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What is the sewer line safety program?

We’ve created a program to identify and correct cross bores. Along with our contractor, we partner with local municipalities to inspect the sanitary and storm sewer lines and take any necessary action.

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Why is it safer for a professional plumber to clear my sewer line?

Professional plumbers know all the precautions to take when dealing with blocked sewer lines. And they know to always call 811 so utility lines can be marked before work begins. In addition, many plumbers can use a camera to inspect the inside of the sewer line — so they can conclude for certain whether the blockage is a cross bore.

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Have an emergency?

If you smell gas, think you have a gas leak, have carbon monoxide symptoms or have some other emergency situation, go outside and call 911 and then call us at 1-800-344-4077.