Franklin arrest was a great lesson: Wright

Getting arrested in the battle to save Tasmania's Franklin River was Penny Wright's biggest political lesson on her journey to fight for the environment to the Senate.

In her first speech to the chamber on Wednesday, the South Australian senator reflected on how the incident in the 1980s protest to stop the river being dammed had shaped her political drive over the years.

"I chose to be arrested although I was jeopardising my future legal career," Senator Wright told the house.

"Down at the Franklin I saw the strength that comes from people standing together for a shared belief in what is right."

She quoted the Cree Indian prophesy: "Only after the last tree has been cut down, only after the last river has been poisoned, only after the last fish has been caught, only then will you find that money cannot be eaten."

Senator Wright identified coal seam gas mining as a huge risk to food production and aquifers on some of the most productive farm land in Australia.

"But some would have us proceed, full-steam ahead, without fully understanding what is at stake," Senator Wright said.

The former lawyer spoke fondly of her work at the "little end of town" helping tenants, people on low incomes and people who live with mental illness sort through legal issues.

She thanked her three children and husband Mark Parnell (a South Australian Greens Legislative Council member) for their love and support.

"My course was set when I met Mark in a crowded lecture after I had been to an early but well-lubricated breakfast of calamari and claret," she said.

"Since then we have spent our life together, much of it on bikes, sharing many joint projects to make the world a better place."

Senator Wright said she was born into a big, rambunctious family, number six of seven children.

"Anyone who has come from a large family knows how important your number is," she said.

"So, I was introduced to politics at an early age."

She also sent a cheerio to her frail mother who was watching her speech on a computer back in Adelaide.

"Hello mum!" she said.