"It's basically happening now as we speak - and it's not going to be long, possibly a week or two when there are not going to be suitably qualified doctors in Westport," the source said.
"People are going to die. I was really reluctant to contact the media but I don't see any other way to force some change," they said.
Emergency staff at both Greymouth and Westport along with their chief medical officers were "hamstrung" in the situation which ultimately came down to budget, "but they're doing the best that they can".
It comes after the Westport News published an account of the vulnerable services for the town including the risk of very unwell patients needing emergency care arriving at a locked Buller Hospital and the risk that security guards would be left to deal with it.
The town's medical Foote Ward is currently open for urgent care from 7am to 10pm daily due to staff shortages, the News reported.
The person who contacted the Greymouth Star this morning said the number of emergency doctors currently available is "very, very small" and within a fortnight the reality of there being no emergency doctor staff at Buller would be "99 per cent done".
"Basically there's not going to be any emergency doctors in Westport," they said.
"There is going to be general practitioners on call (but) general practitioners are not emergency doctors."
Currently there was supposed to be doctors on call or present around the clock but often that meant a Te Nikau Greymouth Hospital doctor being called.
"They're always on call but they're not at the hospital. The GP is on call sometimes... they just do not have the staff."
Clearly the region was not unique in that "everyone is short-staffed at the moment" but the geographical isolation of Westport exacerbated the risk.
At times it was not possible to utilise the Roa West Coast Rescue Helicopter due to flying conditions and St John paramedic availability was also subject to local circumstances.
"You know how far it is from Greymouth to Westport... There's also a hell of a lot of politics about who initiates (calls for service)."
The person said there was a founded belief that Whatu Ora was not going to be able to provide any emergency doctors for the new health hub being built to replace the current Buller Hospital, "and that's going to leave a huge hold for the people up in Westport".
"There was hope that the change to Health NZ was going to make it better but it appears it's going to make it a lot worse."
Whatu Ora West Coast was approached yesterday for comment but has yet to respond.
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