In her statement, Shaw said: “It has been a privilege to lead Yorkshire Water and serve the people of Yorkshire.
“Although there remains a huge amount of work to do, I am extremely proud of what our colleagues have achieved, putting the business on a stronger footing for delivery across all aspects of its work.”
Yorkshire Water said Medalova would join the company on Monday as part of a transition period before assuming the chief executive officer role full time in the new year.
She said: “I am delighted to be joining Yorkshire Water and grateful to the Board for the opportunity to lead the business through its next chapter.
“Yorkshire Water faces huge challenges but also great opportunities for continued improvement and I look forward to working with Nicola Shaw, the leadership team and colleagues across the business as I get up to speed.”
In December last year Shaw said “not being transparent” about receiving £1.3m in shareholder-funded payments across two instalments had been a “mistake”, but had insisted those amounts were “not for me to decide”.
The previously undisclosed payments had come to light the previous August when the government banned Yorkshire Water and five other water companies from paying “unfair” bonuses to bosses.
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