Councillors Emma Clarke, Sam Ferguson, Fiona Gordon, Jono Naylor, Nicola Patrick and John Turkington voted for her - and she voted for herself.
Also standing was the chairman of the previous eight years, Bruce Gordon. He got the votes of David Cotton, Weston Kirton, Wiremu Te Awe Awe, Allan Benbow and himself.
Naylor, a former Palmerston North mayor, was the only person nominated for deputy.
But Keedwell isn't worried the council will appear Palmerston North-dominated. She said every councillor has promised to work for the whole region, not just their patch.
"I'm planning on making sure this is a particularly engaged council. I will be getting out and about lots."
Chairing the council will be a full-time job for her. She and her husband are winding up their business, Professional House Inspections, which will allow her to concentrate on the role.
Keedwell and Patrick actively encouraged candidates with "a strong understanding of environmental issues" to stand in this election, and some were successful.
The council has six new members. Four of the 12 councillors are women, and the average age has dropped by six or seven years. It is a very balanced council, Keedwell said, with strong voices for both the environment and rural industries.
The election for chair was divided, but every councillor congratulated her and offered her 100 per cent support afterward, she said.
Having a woman as chair would also provide some balance, she said, in a council where the chief executive and senior managers are all male.
One of Keedwell's first decisions was not to use her casting vote as chairwoman. Doing so could push controversial things through, she said.
"I was also hoping that it might give some sectors of the community a little bit of peace that I'm not here to try to ram through something radical."
She has a PhD in ecology, and after graduating first worked as an environmental consultant. That went "on ice" for about a decade when she joined her husband in the building business.
Whanganui Horizons councillor Nicola Patrick has been a Keedwell ally for the past three years. She's already excited about the breadth and contributions of her new fellow councillors.
She's hoping this council will be more progressive and innovative and take action on high priority issues. There won't be opposing factions, she said, because people are still loyal to Gordon and because Keedwell's style is respectful and inclusive.
The new council has a really good mix of gender, age and experience, her Whanganui colleague David Cotton said. He's hoping to keep his chairing role of the catchment operations committee when voting is done on November 5.
He doesn't think the council will fall into opposing and "table thumping" factions.
"It's better to sit and listen, and try to get some common ground. You many not get what you want, but you move forward. The biggest thing for me is moving forward," he said.