The adjusted height would make the October 2022 flood peak at 12.14m, higher than the 1974 flood peak of 12.09m.
However, a GBCMA spokesperson said the discrepancy was purely for “historical interest”.
They said it had no impact on the flood response or on planning ahead of the flood or during the emergency.
“The current position of the gauge had no impact on the response to the 2022 floods,” the spokesperson said.
“Current flood data and studies are based on the existing gauge location.
"It was an academic exercise in comparing flood levels, based on records of a historic minor gauge relocation.
“Gauge relocations occur from time to time and this one occurred nearly 40 years ago.”
The GBCMA said there was no indication the gauge was not operating as required but did not clarify what the impact of the river height differentials meant for Loch Garry’s triggers.
Greater Shepparton City Council was approached for comment about what it knew about the flood gauge and what impact it had on responses.
They directed The News to the GBCMA.
Victorian Emergency Services Minister Jaclyn Symes was also approached for comment about if there were any concerns about the gauge being out compared to the 1974 level.
Member for Northern Victoria Wendy Lovell was concerned the information had been kept from the public.
Ms Lovell said she and others she had spoken to who had lived in the area for decades felt sure the floods were higher than the 1974 levels.
"The government needs to come clean and tell us why they and their authorities haven’t advised us of the difference between these floods in 2022 and the ones from 1974,“ she said.
“Things like Loch Garry’s triggers haven’t been updated in decades ... questions need to be answered about key indicators of the flood level.”
Ms Lovell said it was something which should be looked at as part of an inquiry into the floods, which passed parliament last week.
