Electricity is a vital part of our lives. The temporary or long-term loss of electricity can result in outcomes ranging from inconvenience to life threatening. Geomagnetic Disturbance (GMD) events can negatively influence the operation of power grids. Historically, several GMD events have caused permanent damage to critical electrical infrastructure, caused blackouts, affecting the lives of millions of people, resulting in billions of dollars of mitigation measures. AltaLink engaged Teshmont to perform an investigation into the vulnerability of their system to GMD. Teshmont determined the magnitude of GMD currents in AltaLink’s system and the corresponding impacts on system performance for multiple GMD scenarios.