Natural Gas & Propane Safety

Our emergency line is available 24 hours a day.

(888) 467-2669 (Montana)

(800) 245-6977 (South Dakota/Nebraska)

If you smell natural gas, call 911.

Pipeline markers

Pipeline marker in field

Pipeline markers

Markers show the approximate location of pipelines and identify the companies that operate them. The pipeline may not follow a straight course between markers. Pipeline operators must place markers, sometimes called right-of-way markers, at public road crossings, and railroad crossings. These markers indicate the pipeline content, the name of the pipeline operator and the operator’s emergency phone number. Please note that even if the pipeline is marked, you must contact 811 for utility line locates before digging near the marker.

Call before you dig

No project is too small. If it requires a shovel, call 811 or visit call811.com at least two full business days before you begin your project.

How to Recognize a Gas Pipeline Leak

Call 911, if you notice any of these signs of a pipeline leak:

  • An unusual blowing or hissing sound coming from the ground.
  • Dirt or dust blowing from a hole in the ground.
  • Bubbling ponds.
  • Dead or discolored vegetation in an otherwise green area near a pipeline right of way.
  • A fire close to a buried pipeline.

Pipeline Purpose and Reliability

Pipelines are the safest way to transport energy products, including natural gas, crude oil and other fuels. The U.S. Department of Transportation’s Pipeline & Hazardous Materials Safety Administration (PHMSA) regulates pipelines with the help of state partners. According to government and industry statistics, the most common cause of pipeline incidents is improper or unauthorized digging near a pipeline, which is why it’s important to call 811 before you dig. Pipeline operators carefully build, maintain and monitor the integrity and security of their lines.

Excess Gas Flow Valve Notice

If a gas service is installed to your home, you have the option to purchase an Excess Flow Valve (EFV) to be installed by NorthWestern Energy. An EFV is intended to stop the flow of gas if the service line is severed. The EFV Valve is placed in the service line where it leaves the gas main. 

 An EFV will stop the flow of gas only if the service line is severely damaged. It is important to note that an EFV will not protect you from a leak or broken line inside your home, or a small leak on the line in your yard. An example of when the valve provides protection is in the event the gas service is damaged from digging or extreme ground movement. 

 As required by the U.S. Department of Transportation (DOT), we are notifying you that an EFV that meets the minimum prescribed DOT performance standards, is available for installation on your natural gas service line.

The cost of installing the EFV will need to be evaluated by an engineer.  If you are interested, please contact your local NorthWestern office to set up an appointment.  Payment is required prior to installation of the EFV.  

Excess Gas Flow Valve FAQs

The cost of installing the EFV will need to be evaluated by an engineer.

If you are interested, please contact your local NorthWestern Energy construction office to set up an appointment. This payment is required prior to installation of the EFV.

There is no way to visibly check. You most likely already have an EFV installed if:

  • Your home/building was built since June 2008
  • Your gas service line was replaced since June 2008
An EFV is intended to stop the flow of gas if the service line is severed. The EFV is placed in the service line where it leaves the gas main. An EFV will stop the flow of gas only if the service line is severely damaged. It is important to note that an EFV will not protect you from a leak or broken line inside your home, or a small leak on the line in your yard. An example of when the valve provides protection is in the event the gas service is damaged from digging or extreme ground movement.