"Everyone's phone just went nuts. It was awful," she said.
At Auckland Airport on her way home, flight after flight was coming in from Christchurch, bringing shocked people to safety. Other flights were filling with people heading south to help.
Ms Wrigglesworth's employer, Opus International Consultants, asked her whether she would be willing to go to Christchurch. From then until the end of the year she was usually there from Tuesday to Friday.
The first trip was an eye-opener. There was an earthquake that prevented her plane from landing, and constant tremors after it got down. Rescuers were still looking for people in the rubble, and there was no cordon around what became the red zone.
Trips into it entailed wearing a hard hat and other safety gear, but she wasn't scared.
"Our engineers had been through it since September. They knew what they were doing."
She remembers seeing a table outside the hotel across the road with a tourist guidebook that had been sitting open on it for days.
"Nobody was around and it looked like everyone had just vapourised."
She began collecting and writing stories about the quake situation, first for fellow Opus engineers and then for the media and public.
Stories changed as the recovery phase began, shakes continued, and buildings were assessed and re-assessed. There were so many she could not tell them all.
Back in Wanganui this year, Ms Wrigglesworth carried on with her four-day-a-week job with Opus, and used the fifth day for freelance engineering communication work in her own business, Ink Communication.
She is a regular contributor to New Zealand's engineering magazine and feels lucky to combine two things she likes - writing and engineering.
Chronicle readers will remember her weekly articles about Wanganui engineering features during 2007-8. They explained such things as how traffic lights work, how the Sarjeant Gallery makes use of natural light, and how Ro-Gliders protect Wanganui Hospital from earthquake damage.
She hoped the articles would help Wanganui people see their surroundings with new eyes.
Those who predicted readers wouldn't be interested in engineering subjects were wrong, and Ms Wrigglesworth said that did not surprise her at all.
"Ordinary people actually are interested in engineering, and they should be."
She studied mechanical engineering at Canterbury University, graduating in 1994, then worked for Wanganui District Council, MWH and Opus, as well as having four children.
She has been with Opus for five years, and said the global business grew out of New Zealand's public works department and still had a head office in Wellington. It is now in Australia, Canada and the United Kingdom, has Malaysian owners and is moving into Asia and the Middle East.
Ms Wrigglesworth's new job will be essentially doing for Opus in Australia what she has been doing in New Zealand. She knows she has a lot to learn about Australian engineering, and says it is going to be exciting. "It's a new role, so I can shape it how I want."
