Liv Garfield, CEO of BT's Openreach business, has been appointed as the chief executive of water and waste water provider Severn Trent.
Garfield, 38, will take up the role when current CEO Tony Wray retires in spring 2014. Her appointment increases the number of women CEOs in the FTSE 350 from 14 to 15.
Garfield has been at BT since 2003 and has been CEO of BT's local access network division since April 2011. In this role, she has overseen the company's £2.5 billion commercial rollout of fibre broadband.
She said the Severn Trent role was an opportunity to take on a "fresh challenge".
"Our commercial programme to bring fibre broadband to two-thirds of UK premises is almost complete, whilst BT's public sector broadband partnerships are making good progress," Garfield said.
Other roles she held at BT included group director of strategy and regulatory affairs, where she oversaw the company's fibre broadband strategy, and managing director of commercial & brands and UK customer services director, within BT's Global Services division. She is also a non-executive director of Tesco.
Garfield joined BT from management consultancy Accenture.
Severn Trent's chairman, Andrew Duff, said: "Liv brings experience of managing customer service delivery and complex organisations in a regulated environment."
BT said that it will be announcing Garfield's replacement in due course.
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