Ngata was inspired to action when she watched a documentary about albatrosses dying after consuming plastic waste from the so-called Great Pacific garbage patch.
The film documented the slow death of the seabirds after they had consumed plastic from the massive island of floating rubbish, estimated to be the size of Texas, that drifts around the Pacific Ocean between Asia and North America.
"At that point I decided I was out, I didn't want to be responsible for that," Ngata said. "I didn't want that lighter inside that bird to come from me."
As a teacher of environmental studies at Te Wananga O Aotearoa in Gisborne, Ngata was already passionate about environmental issues, but decided she needed to do more.
From the start of 2014, she set about recording how much plastic waste she was creating and documenting her efforts to cut it down.
"I didn't know how much plastic waste I was creating until I made a concerted effort to cut it out."
Friends and family encouraged her to write about her experiences, which led to her blog, The Non-Plastic Maori.
"The idea is a plastic Maori is an inauthentic Maori and this is very much a discussion around what it means to be a kaitiaki [guardian], what it means to be Maori," Ngata said.
"One of those ideas is we are equal members of the ecology around us."
The Herald spent an hour with Ngata at Gisborne's Kaiti Beach last week picking up litter including cigarette butts, fast-food wrappers, fishing tackle, sunglasses and discarded sandals.
The amount collected was sobering.
"For me it's about my relationship with this place," she said. "Once people start doing beach clean-ups they realise how often they look past rubbish."
As part of her research into the problem locally, she once sat outside a Gisborne supermarket and counted the number of plastic bags coming out, and was shocked by what she saw.
"In one hour, 660 plastic bags came out."
There are already moves to make the Gisborne region plastic-bag-free. Plastic Bag-free Tairawhiti (PBFT) was formed in May and promotes alternatives to plastic. The group addressed Gisborne councillors this week saying 100,000 plastic bags went to the area's landfill each week.