Preventative system maintenance is a critical component of reliability and operational excellence. Our Comprehensive Operations and Maintenance (O&M) programs bring quantifiable increases in reliability and efficiency to ensure a high-performing system.

ITC achieved 100 percent compliance with maintenance requirements under NERC standards in an audit of ITC’s three operating companies.

Operation and Maintenance expenditures are not investments on which ITC earns a return. Instead, they reflect the commitment of ITC to conduct its transmission business in a way that serves customers best by providing a system that works more efficiently and with greater reliability.

System Maintenance: Critical to Reliability

ITC’s aggressive and comprehensive maintenance programs help bring quantifiable increases in transmission system reliability.  We target unreliable, high-maintenance equipment for upgrade or replacement with state-of-the-art units that are more dependable, more environmentally friendly and less maintenance-intensive.  These efforts have contributed to a consistent pattern of fewer and shorter outages across ITC’s three operating systems.

There are four components to ITC’s maintenance practices:

  1. Look at all individual components that ultimately affect reliability, and make sure each of those items get the right maintenance. 
  2. Complete 100 percent of the maintenance every year. 
  3. ITC has a “find it, fix-it” mentality; if some deficiency is found – fix it, so it doesn’t become a bigger problem later. 
  4. Continuous improvement is the hallmark of any good organization, looking to drive higher performance, lower costs, and better ways of taking care of this complex transmission system.

Preventive Maintenance

ITC Conducts Aerial Patrols in Spring and Autumn

Regularly scheduled inspections and testing of transmission lines, structures and substation equipment identifies equipment in need of additional maintenance or replacement to ensure reliability.

  • Regular aerial and ground patrols of transmission lines identify damaged or worn equipment, such as cracked insulators or frayed wires.
  • Real-time monitoring using advanced technology to identify substation transformer issues.
  • Transmission circuits with repeated outages are investigated so action can be taken to improve reliability.

This results in less reactive maintenance because preventive maintenance addresses and resolves potential issues before they cause problems. 

In spring and autumn, ITC conducts its aerial patrols of high-voltage transmission towers and lines. The helicopter patrols are conducted to provide an overall status of the overhead transmission system. They include inspections of steel towers, wood poles, conductors (wires), insulators and other equipment. Crews check for damaged or worn equipment and vegetation hazards.

These patrols are a North American Electrical Reliability Corporation (NERC) requirement for ITC’s vegetation management program, support proactive maintenance objectives, and are in line with the company's model for operational excellence.

Integrated Vegetation Maintenance Program


ITC maintains an integrated vegetation management program to protect electric reliability and public safety.  Trees and high voltage power lines are a hazardous combination. Tree interference with transmission lines is a leading cause of electric power outages and poses a safety threat to the public. Our society depends upon electricity, so outages or blackouts are inconvenient, costly and potentially dangerous. Proper vegetation management is essential to preventing such outages.

ITC’s twice-a-year aerial patrols of the transmission system help the company meet the federal zero-outage vegetation mandate by identifying and addressing potential vegetation threats before they can cause problems. 

Learn more about ITC’s vegetation management policy

Vegetation Management

Maintenance through performance-driven asset management 


  • Identify relevant metrics to measure reliability and quantify acceptable levels of asset performance.
  • Review and organize historical outage records, inspection records and maintenance events.
  • Analyze data to identify worst performing circuits.
  • Apply Quanta Technology’s Results-Oriented Asset Management asset renewal program to provide a forward, statistical model of asset maintenance activities to forecast future performance of these circuits.
  • Correlate the changing probability of failure with the age of the circuit to create an operational forecast sufficient to identify candidates for rebuild, maintenance or further inspection.
T&D World Magazine: ITC Drives Performance With Asset Management