The city itself is on the cusp of big change, including Transmission Gully nearing completion and the Government's $1.5 billion investment in housing and the revitalisation of eastern Porirua.
Coffey said the city needed strong leadership to drive that change.
"I've got the experience, I've got the skills, I've proven that over the last nine years, so I think it's time."
The mother of five and trained primary school teacher said the time was right for her family as well.
Coffey is currently the chair or the City Direction Committee, which she calls the "engine room" of the council.
In her spare time she teaches a hip-hop class.
Her mayoral campaign will also prioritise investing in good infrastructure to protect Porirua Harbour, which has been degraded after years of development.
"We love our harbour. It's important to us and we need the infrastructure to keep away the sewerage, to keep out infiltration, to keep out the heavy metals that come off brake pads, and the zinc that comes off rooves."