Natural Gas & Propane Safety

The Commission regulates natural gas service reliability and ensures compliance with safety standards for 1,410 miles of natural gas distribution mains, 84 miles of intra-state transmission pipelines (including the five-mile private pipeline operated by Woodland Pulp, LLC), and 40,812 services. These facilities were in service throughout Maine as of December 31, 2021, as noted in the operators’ annual reports to the U.S. Department of Transportation’s Pipeline and Hazardous Material Safety Administration (PHMSA) filed in March of 2022. In addition, the Commission enforces safety standards for approximately 590 Liquid Propane Gas (LPG) distribution facilities that provide LPG service to multi-unit housing complexes, commercial buildings, and other facilities where LPG system failures would likely impact large numbers of people.

The Commission derives its authority for safety oversight from both state and federal laws. Chapters 420 and 421 of the Commission’s rules adopt federal safety regulations for pipelines that transport hazardous gases to protect the public and govern the safe operation of distribution and intrastate transmission facilities within the State. The Commission is also a certified agent for PHMSA. In this role, the Commission ensures that intrastate natural gas transmission and distribution systems comply with federal pipeline safety standards and corresponding state regulations through operator inspections. Link to PHMSA's Inspection Page   Additionally, the Commission investigates natural gas safety incidents and pursues enforcement actions for violations of the federal or state safety regulations.

PHMSA’s Pipeline Safety Stakeholder Communications – Maine Enforcement Program

PHMSA’s Pipeline Incident 20 Year Trends, where incident data for Maine and other states may be found.


Maps of the intrastate natural gas transmission pipelines under the safety jurisdiction of the MPUC may be found at National Pipeline Mapping System.

Inspections, Statistics, and Data

Natural gas utilities must receive the MPUC's authorization to construct and operate intrastate pipelines.  The MPUC's review of these projects primarily involves an engineering review of the utility's construction plans to ensure that the pipeline will conform to all American Standard Code of Pressure and Piping standards to ensure that pipeline is constructed and operated safely.  The MPUC does not review and approve siting and routing plans from an environmental standpoint, this review is conducted by the Maine Department of Environmental Protection or the Maine Land Use Planning Commission, and local municipal government.

The following facilities fall under the MPUC's safety jurisdiction:

  • Intrastate natural gas transmission pipelines;
  • Natural gas distribution systems;
  • Utility operated liquefied natural gas facilities; and
  • Propane distribution facilities falling under the jurisdiction of 49 CFR 192.1.

    Operator Reference Information 

    Jurisdictional LP Resources

    Laws and Rules

    If you have any questions, please call the MPUC at (207) 287-3831 or toll free at (800) 452-4699.