One of Victoria’s oldest-known military bunkers unearthed at Williamstown’s Burbank Oval seven years ago will be buried again.

The Williamstown Right Battery was discovered in January 2011 when a tank was being installed as part of the Williamstown Football Club’s $8 million expansion.

The bunker was built in 1862-1863 in response to a perceived Russian threat as a result of the 1853-1856 Crimean War, and housed cannons and ammunition.

Heritage Victoria believes the bluestone bunker was backfilled when the grandstand was built in 1930.

The battery contains three magazines, two of which have already been filled in.

Plans to preserve and restore the last magazine have been abandoned for now.

Hobsons Bay mayor Angela Altair said the historic site would be filled in with a material that could one day be taken out.

“The magazine is regularly filling with ground and rain water – it needs to be drained by hand regularly, is a trip and fall hazard and is not safe,” she said.

“Stagnant water has also caused us concerns from a public health perspective.

“As a result of, and in accordance with, archaeological practice and guided by Heritage Victoria, the principal magazine will soon be filled with a reversible, Heritage Victoria-approved material.”

Historian Brian Haynes said the bunker had poor drainage and there had been issues with the water table since it was built.

“It’s had issues from day one and in a number of the newspapers of the 19th century it does talk about three foot of water in the magazine,” he said.