Two concrete bunkers designed to protect Brisbane residents from bombing raids during World War II were uncovered this week by the team redeveloping the Howard Smith wharves near the Story Bridge in the inner city.

Developers of the site were aware of the air raid shelters — one a pipe design and one a pillbox — but had yet to clear the vegetation concealing them from view.

Graham Quirk (second from left) at one of the uncovered bunkers, which the city will restore. ( Supplied: Brisbane City Council )

Lord Mayor Graham Quirk said the bunkers would be restored as soon as possible and were "a wonderful find for Brisbane".

"These shelter sheds were very much a part of WWII history," he said.

"They are part of 230 air raid shelters built in this city around 1941 and 1942, just prior to the arrival of US General MacArthur when Brisbane became one of the four big centres for Allied forces defending freedom."

Brisbane slow to protect itself from bombing

Christina Ealing-Godbold, a senior research librarian at the State Library of Queensland, explained that Brisbane had been a bit slow coming onboard with air raid shelters.

"In September 1939 they said distinctly, 'air raid shelters to protect us from bombs are just not necessary'," she said.

"Poor old Brisbane was a sleepy place and most Brisbane people had no experience of anything quite as terrifying as bombs."

That all changed when Australia entered the Pacific War following the bombing of Pearl Harbour in December 1941, with Brisbane becoming one of four major centres for Allied forces in the region.

Fun cancelled for trench building day

"The threat of Japanese planes flying overhead and bombing was considered a great likelihood and as you know, they bombed Darwin and there were also submarines off the Queensland and New South Wales coast," Ms Ealing-Godbold said.

"By 1944 we had 275 brick or concrete structures, [including] pillboxes right down the middle of Elizabeth Street in the city, but there were many more in back gardens and parks, and every school had to have one.

Hidden for many years, the concrete bunkers have been rediscovered by builders. ( Supplied: Brisbane City Council )

"The trench construction was given out in the newspaper, where every home owner and local government was told how to build one.

"Most of them were dug by teachers, working bees and families.

"One Sunday in 1941, it was announced that all trains and entertainment had been cancelled because everyone was going to stay home and build their trench.

"So the entire city was forced to stay home and dig their trench."

The brick bomb shelters built on one side of Elizabeth Street in 1942. ( Supplied: State Library of Queensland )

Ms Ealing-Godbold said there were a number of different types of air raid shelters in Brisbane.

"Generally they were either tunnels or bunkers dug in the earth or pillboxes at road level," she explained.

"Most of Brisbane's bunkers are in the suburbs and parks and were hand-dug trenches with corrugated iron on top of them."

She said they had to be at least three metres long and fit six people.

Ugly landmarks a part of city's history

Cr Quirk said the unearthed bunkers were designed by Brisbane City Council architect Frank Costello, and are just two of many other Costello-designed shelters around the city.

An air raid warden tests his equipment in Brisbane, October 1942. ( Supplied: State Library of Queensland )

"People probably look at a concrete bus shelter and think 'what an ugly concrete thing that is' without realising that it's a part of our history," he said.

"They probably wonder why council is not upgrading it but it's a part of that war history — that's why it's being retained."

Luke Fraser from the HSW consortium said they had known of the presence of the bunkers so it was not really a surprise when the vegetation was cleared and the bunkers were found.

"We've spent a lot of time investigating the wharves and we're really excited to find little elements like the bunkers," he said.

"The whole site has these hidden little treasures throughout it and lots of little heritage pieces."

Air raid shelters to be preserved

Mr Fraser confirmed developers were committed to preserving the site's history.

"Our commitment and philosophy throughout is to, wherever possible, protect those [heritage pieces], reuse them and take all the existing building material and repurpose them," he explained.

Cr Quirk joked that the bunkers would make a great office because they are so quiet. ( Supplied: Brisbane City Council )

While Cr Quirk said meals were expected to be served at the wharf complex by the end of this year, there would not be a bunker coffee shop any time soon.

"I don't know that they're big enough for a coffee inside," he said, laughing.

"I thought they might be more a Lord-Mayoral getaway.

"They're very quiet so you can do some good thinking inside those bunkers."

The wharves, built in the 1930s in conjunction with the Story Bridge, were initially leased to shipping firm Howard Smith and Co.

More recently the wharves have been used by the Queensland water police and government works departments for storage.