PORTLAND – The former St. Dominic Roman Catholic Church, which served for generations as spiritual cradle of Portland’s Irish-American community, is in line to become the property of the city.

The City Council next month will consider a deal in which Portland would pay $50,000 to the Roman Catholic Diocese of Portland for the red-brick building on State Street and the former parochial girls’ school building next door.

Although they are not certain what to do with the property, city officials said the church building is too important, architecturally and otherwise, to sit vacant and be allowed to deteriorate.

“It’s a significant structure in the community,” said Mark Adelson, Portland’s director of housing and neighborhood services.

“If the city’s involvement is needed to see that this property is taken care of, we’ll do that.”

The church, which at one point had 4,000 parishioners, closed in 1998 after the dwindling congregation was unable to support the cost of needed repairs, estimated at $1 million.

The city has done some initial research into possible alternatives for reuse. For example, Adelson toured a church in East Boston that was converted to a day care center for 100 children.

The proposed agreement between the city and the diocese states that at least 40 percent of the redevelopment of the girls’ school building will be affordable housing.