The head of Hunter Water has resigned to take up a new job in Queensland.

Managing director Kim Wood is heading north.

Hunter Water chairman Terry Lawler says it was surprising news, and has thanked Mr Wood for driving substantial change in the organisation.

Mr Wood oversaw the sale of Hunter Water's head office building in Newcastle and its engineering arm Hunter Water Australia during his time in the role

He got the ball rolling on the sale of land set aside for Tillegra dam, and also outsourced management of the Hunter’s 25 waste water treatment plants.

Mr Lawler said these moves brought major savings.

Mr Wood also opened the Hunter's first underground reservoir, The Res, for public tours, which were keenly undertaken by locals and tourists.

Mr Wood will leave in coming weeks, with the board expected to begin searching for a replacement immediately.