Reaney has returned to the energy giant as director of installations. He has been succeeded at Thames Water by Kelly MacFarlane.
Before joining Thames Water in 2014, Reaney held various positions at Centrica subsidiary British gas, including commercial director of residential services and director of sales, commercial and customer services.
He was also chief marketing officer at US energy retailer Direct Energy between 2010 and 2012.
Commenting on his departure, Reaney insisted that he loved Thames Water, but was attracted to the role at Centrica.
“Thames is a great business, it is definitely embracing the customer agenda,” he told Utility Week. “But I got approached about the installations role within Centrica, which is the role I always aspired to before I left. It was the role that really appealed to me, and I was very motivated around the new model that Centrica is embracing, and can see how it could work for Centrica and the customer.
“It is a part of the business that I knew through my sales and commercial activities. It is a brand close to my heart, and it is a retail business, which is in my DNA.”
This is the latest in a long line of senior staff changes at Thames Water, which began with the November 2015 announcement that former chief executive Martin Baggs planned to step down. He was succeeded by former telecoms boss Steve Robertson, who took up the post in September 2016.
In April 2016, Graham Southall, former managing director of Thames Water Commercial Services, and Rupert Kruger, Thames Water’s former head of business retail announced they would leave the water company that year, ahead of the opening of the non-household water market in April 2017.
In the same month, former chief financial officer Stuart Siddall announced that he would retire at the end of 2016. SSE managing director of finance Brandon Rennet was appointed to succeed Siddall, and will take up the post in March this year.