New Brunswick's first Catholic cathedral is seeking recognition and protection under the provincial Heritage Conservation Act.

The Cathedral of Immaculate Conception opened in Saint John in 1853, after thousands of Irish Catholic immigrants flooded into the city.

It is one of the few structures that survived The Great Fire of 1877.

Bishop Robert Harris says the cathedral, located on Waterloo Street, needs about $10 million in repairs, including the roof, exterior sandstone walls and inner plaster walls to address a water leak and water damage.

Harris says a provincial heritage designation wouldn't result in any government funding, but might create more public awareness about the Gothic Revival-style building, which could lead to support for its restoration.

The Cathedral of the Immaculate Conception

The Cathedral of the Immaculate Conception, which opened in Saint John in 1853, needs about $10 million in repairs. (CBC)

He contends the cathedral is an important landmark.

"I never look at this kind of a building as just a museum piece," he said. "It's a place of worship and countless numbers of men and women have gathered here to celebrate the joys of life and also to bring their pain and suffering to the Lord."

Elsie White, who attended noon mass on Monday, is one of the cathedral's devout fans.

"When I first came here, I thought it was the most beautiful church I'd ever seen in my life," she said. "And I've been around the world, many, many times and I was very taken with this church."

The cathedral marks a coming of age for Saint John Catholics, said Harris. The New Brunswick diocese separated from Charlottetown and the episcopal seat was established in Saint John.

Over the decades, the cathedral has also been supported by the Scottish, Lebanese, and Acadians, said Harris.

"This was really a product of all these groups, men and women who were here. And they had one thing in common — they were all Catholic and they wanted this beautiful place to be their place of worship. So they made sure it was built," he said.

The plans for the building were drafted in New York, the original pipe organ came from England, and the stained glass windows were made by the Royal Bavarian Stained Glass Factory in Munich.

The church has undergone many upgrades over the past 160 years. Some of the original stained glass windows had to be replaced, and the current pipe organ came from Quebec in 1952.

But soon it will need major repairs, and the size of the congregation is shrinking, said Harris. That's why the Diocese of Saint John is pinning its hopes on the heritage designation, he said.