Stadium owners Taranaki Stadium Trust say a safety-first approach is behind the reason to make the stadium unavailable in 2018, after geotechnical testing on the stadium's West Stand showed that it was a significant earthquake risk.
Reports into the West Stand were commissioned after a November report found the stadium's East Stand was earthquake-prone.
"It's a real blow and we apologise to everyone involved. The Trust informed key partners, including the TRFU, of the report's findings yesterday," says TST trustee Mike Nield.
Nield said it was too early to speculate on the future of the stadium but the TST would continue investigating the next steps.
"This is a blow but we remain committed to having a facility in Taranaki capable of hosting top-flight sporting events.
"We'll be looking at our options and while the loss of Yarrow for 2018 is a setback, it gives us opportunities to look at some of the different choices available to us."
New Plymouth Disctrict Council COO Kelvin Wright said safety of the public was the primary concern.
"This is hugely disappointing for players and fans who will be inconvenienced but safety comes first.
"We take public and staff safety very seriously and have taken a proactive approach ever since issues were first discovered."
Taranaki are the current holders of the Ranfurly Shield.
