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Important Safety Information About Underground Gas Pipelines Near You

Resources & information
Pipeline Association for Public Awareness’ (PAPA) newsletter*
This annual newsletter, provides articles to educate public officials about pipeline safety and awareness.
High Consequence Areas (HCAs)
Are primarily locations that are heavily populated and have gas transmission pipelines in the vicinity. Less populated areas can also be classified as HCAs if they meet specific additional requirements, such as buildings accommodating low-mobility residents or areas where people gather for a specific number of days per year.
Non-High Consequence Areas (Non-HCAs)
Are primarily locations that are not heavily populated and/or do not have gas transmission lines in the vicinity.
Emergency preparedness
Natural disasters and emergencies can strike without warning. Learn what to do with your gas meter and gas appliances before, during and after an emergency.
Did you know?
Commonly asked questions
Q1. How should I coordinate city planning and development projects with SDG&E?
Contact us and we can guide you through safe building around our major gas pipelines. We encourage you to review the information provided by the Pipelines and Informed Planning Alliance (PIPA) because the decisions you make can affect the safety of the community surrounding the pipeline.

Q2. How do I know where natural gas pipelines are located?
The approximate locations of major natural gas pipelines can be found online at National Pipeline Mapping System* or on We also place yellow pipeline markers next to our major pipelines near intersections and railway crossings to identify approximate locations of our lines and provide an emergency phone number.

Q3. Based on population and pipeline locations, do I have High Consequences Areas in my city or county?
According to U.S. Department of Transportation guidelines, Sanclemente has No HCA designation status.

Q4. What information does SDG&E use to determine HCAs? How can I help?
SDG&E uses a variety of publicly available data sources from the state and county sources, custom aerial photography and our own field reports to identify buildings and outside gathering areas near our pipelines. SDG&E categorizes these building and gathering sites as single family residences or Identified Sites. Identified Sites include businesses, multi-family apartment buildings, churches, hospitals, schools, outside gathering areas, locations containing people with impaired mobility and any other site where there is an opportunity for 20 or more individuals to congregate.

You can help us by providing feedback on our categorization or notify us about sites that may not be incorporated into our records. Pipeline Watch is a 3rd party website which will allow you to view our building categorization and provide feedback. The information provided to SDG&E will be evaluated and incorporated into the HCA determination process. Please access Pipeline Watch here.

Q5. If there is a major natural gas leak, how do I get emergency crews there as fast as possible?
Work with the 911 dispatchers in your city to understand and follow the Pipeline Emergency Operations Standard*(PDF).

Q6. How can I make my city safer and prevent pipeline incidents?
Public officials are encouraged to work with contractors to have buried utility-owned lines marked by obtaining a valid 811 ticket* at least two working days before digging. Contractors must do so by law. Homeowners should call, too. This is a FREE service and can help prevent injury, costly property damage and loss of utility service.

Q7. Can I rely on my sense of smell alone to be alerted to a potential natural gas leak?
Most of the time “the nose knows” the distinctive odor of natural gas, but not always. Some people may not be able to smell the gas odorant under certain conditions, such as if they have a diminished sense of smell or are experiencing “odor fatigue”, where the presence of other odors may mask the smell of the gas odorant, and where the reduction or loss of gas odorant, known as odor fade, occurs. This is why you should learn how you can also be alerted to a gas leak through your senses of sight and hearing.

Q8. What should I do when there is a gas leak?
If a natural gas leak is suspected, remain calm. Don't smoke or light a match, candle, or other flame. Don't turn electric appliances or lights on or off or use any device that could cause a spark. Be aware that natural gas leaking from a plastic pipe can create static electricity which can ignite the natural gas. Immediately leave the area and, from a safe location, call SDG&E at 1-800-411-7343, 24 hours a day, seven days a week, or call 911.

Q9. Why does SDG&E prune or clear trees in my city?
We must have unobstructed access along our pipeline right-of-way to maintain and operate our facilities and to quickly respond to any pipeline emergency. In addition, tree roots can damage our pipelines.

Q10. What does SDG&E do to maintain its pipelines and protect the public?
SDG&E uses pipelines to deliver natural gas to residential and business customers for heating, cooking, manufacturing and other purposes. Because safety is our top priority, we routinely perform pipeline safety tasks, including patrolling, testing, repairing and replacing pipelines, and have ongoing technical training and testing of employees. Our integrity management plans are available for review and outline our ongoing safety and maintenance activities. We also maintain an ongoing relationship with emergency response officials, in order to prepare for and respond to any pipeline emergency.

Q11. Where do I get more pipeline safety information?
Go to You can also contact your local SDG&E public affairs manager if you have questions about public safety, need additional information on the integrity management program, land use practices, emergency preparedness, or other matters.