Direction and Leadership
ENMAX Corporate Governance
Executive Team
Meet the Executive Team
Mark Poweska
President & CEO
Mark is the President and CEO of ENMAX since 2022. In this role, he oversees ENMAX’s regulated, competitive and energy retail businesses, ensuring ENMAX’s strategic direction enables reliable energy for customers now and in the future. He also serves as Board Chair of Versant Power, ENMAX’s Maine-based regulated transmission and distribution provider.
Sheri Primrose
Chief Financial Officer
Sheri joined ENMAX in 2006 and has held progressively senior roles in the organization. As Chief Financial Officer since 2023, Sheri is responsible for the company's financial functions, including accounting, audit, treasury and corporate finance. She also serves on the Board of Versant Power, ENMAX's Maine-based regulated transmission and distribution provider.
Greg Retzer
Executive Vice President, ENMAX Power
Greg joined ENMAX in 2019 and has led ENMAX Power since 2024. He is responsible for ENMAX’s Alberta-based regulated transmission and distribution business, which owns, operates and maintains the system in and around Calgary and is regulated by the Alberta Utilities Commission.
Erica Young
Executive Vice President, ENMAX Energy
Erica joined ENMAX in 2016 and has led ENMAX Energy since 2024. She is accountable for ENMAX's competitive energy businesses including electricity generation, retail and customer operations, wholesale commodity trading and commercial programs.
John Flynn
President, Versant Power
John joined as President of Versant Power in 2020 and is responsible for ENMAX’s Maine-based regulated transmission and distribution business. As the second-largest utility in the state of Maine, Versant Power provides electricity and customer care services to residential, commercial and industrial customers, and is fully regulated by the Maine Public Utilities Commission and the Federal Energy Regulatory Commission.
Brandie Yarish
Chief Human Resources Officer and Executive Vice President, Safety and Information Technology
Brandie leads ENMAX’s people strategies, organizational development, health, safety and environment programs and practices, as well as the IT team, and has been with the organization since 2018. She also serves on the Board of Versant Power, ENMAX's Maine-based regulated transmission and distribution provider.
Sarah Stevens
Senior Vice President, Regulatory and Chief Legal Officer
Sarah joined ENMAX in 2013 and has held progressively senior roles in the organization. In her current role since 2024, she leads the legal, regulatory, compliance and corporate secretary functions at ENMAX. Sarah also serves on the Board of Versant Power, ENMAX's Maine-based regulated transmission and distribution provider.
Marie Rajic
Senior Vice President, Corporate Affairs
Marie joined ENMAX in 2024 and leads the Public Policy and Government Relations, Shareholder Relations, Sustainability and Indigenous Relations, and Communications and Community Impact teams, focusing on shaping ENMAX's reputation and fostering relationships with government bodies, regulatory agencies and our Shareholder, The City of Calgary.
Board of Directors
To contact our Board of Directors, please email boardofdirectors@enmax.com.
Meet the Board of Directors
Charles Ruigrok
Charles Ruigrok joined the ENMAX Board in 2010 and is the Chair of the Board, having previously served as Chair of ENMAX’s Audit Committee and as Board Chair of Versant Power, ENMAX’s Maine-based transmission and distribution business. Mr. Ruigrok also served as ENMAX’s President & CEO, on an interim basis, between 2011-2012 and 2021-2022.
Mark Poweska
President & CEO
Mark is the President and CEO of ENMAX since 2022. In this role, he oversees ENMAX’s regulated, competitive and energy retail businesses, ensuring ENMAX’s strategic direction enables reliable energy for customers now and in the future. He also serves as Board Chair of Versant Power, ENMAX’s Maine-based regulated transmission and distribution provider.
Nipa Chakravarti
Laura Formusa
Laura Formusa joined the ENMAX Board in 2017 and is the Chair of the Human Resources Committee. She also serves as Board Chair of Tantalus Systems Holding Inc., as Chair of the Corporate Governance and Nominating Committee of Equitable Life Insurance Company of Canada, and as a Director of 407 International Inc. Laura has also served on the Board of Governors of York University.
Eric Markell
Eric Markell joined the ENMAX Board in 2016 and is the Chair of the Audit Committee. Eric is a member of the Board of Trustees and Treasurer of the United States Eventing Association Foundation, a 501(c)(3) entity where he also serves as a member of its Investment Committee.
Barbara Munroe
Barbara Munroe joined the ENMAX Board in 2021 and is the Chair of the Corporate Governance Committee. Barbara is also the Board Chair of Veren Inc. (formerly Crescent Point Energy Corp.) and is actively involved in volunteer and non-profit organizations. She is the former vice-chair of the Alberta Cancer Foundation’s Board of Trustees, and a former member of the Arthur J Child Comprehensive Cancer Center campaign task force which raised over $250 million, the largest capital fundraising campaign in Alberta’s health sector history.
Byron Neiles
Byron Neiles joined the ENMAX Board in 2022 and has over 30 years of experience in the energy industry. In 2024, he retired as the Executive Vice President & Chief Administrative Officer at Enbridge Inc. in Calgary, where he led the IT, human resources, real estate, supply chain management, public affairs, communications and sustainability teams.
Dr. Chika Onwuekwe K.C.
Elise Rees
William Taylor
William (Bill) Taylor joined the ENMAX Board in 2020 and has over 30 years of experience in the energy sector.
Before joining ENMAX, Bill spent 21 years at TransCanada Corporation (now TC Energy) where he held various senior executive positions. Bill held the position of Executive Vice-President and Division President, Energy at TransCanada and prior to that, held various senior executive positions, including Senior Vice-President, Power. He was responsible for profitability and growth of the company's power business, non-regulated gas storage and its non-regulated joint ventures in Canada and the United States.
Bruce Williamson
Bruce Williamson joined the ENMAX Board in 2020 and has over 30 years of experience in the energy sector.
Before joining ENMAX, Bruce held many senior executive positions including: President & CEO and Board Chair of Southcross Energy Partners; President & CEO and Board Chair of Cleco Corporation; President and CEO and Board Chair of Dynegy Corporation; President & CEO of Duke Energy Global Markets; Board Chair of Southcross Holdings; an independent Board member of Questar Corporation; and served on the UH Chancellor’s National Advisory Council. Bruce also spent four years with PanEnergy Corp as SVP, Finance and Corporate Development and prior to that, he spent 14 years with Shell Oil and various Shell affiliates in a variety of positions, primarily in exploration and production and finance where he rose to be Assistant Treasurer of Shell Oil Company (Shell USA).