The local authority is to conduct a study of underused places of worship in Dublin with a view to buying churches that have been worst affected by the drop in attendances.

The study, which will be conducted in partnership with the Heritage Council, will also seek to identify the areas and denominations to have suffered the heaviest losses in terms of people regularly attending places of worship.

A tender for the study was advertised on the government's etenders. gov. ie website earlier this week and it is intended that the survey will be conducted towards the end of this year.

According to the advertisement, the study will seek to establish a register of underused places of worship of all denominations in the city, as well as tracking the decline in congregation numbers experienced.

The city council hopes to identify sites in the city that may be purchased from religious orders and given new uses.

The council has defined an underused place of worship as being "either closed for worship or one that has experienced a significant fall in congregation numbers, or one in which worship/service takes place on an infrequent basis."

The Heritage Council is co-funding the study in a bid to ensure that any buildings purchased from religious orders would retain their architectural value. According to Michael Starrett, chief executive of the Heritage Council, the study will represent a chance to put to use buildings that have suffered from a decline in the church-going population.

Starrett said that the "change in society" that had led to a fall in congregation figures in certain churches should not lead to buildings of significant heritage value falling into disuse.

He cited the former church that now houses the Dublin Tourism office on Suffolk Street as an example of how churches can be renovated for new uses without losing their architectural value.

"What the study can identify is which buildings in the city are being used infrequently because of the decline in congregation figures, " he said. "The Heritage Council's interest in this project is ensuring that whatever new use the buildings are put to, the heritage value of the buildings remains."

A spokesman for the Dublin diocese said that congregation figures for inner-city churches in the capital had decreased over recent years, but added that the Catholic church was currently attempting to reinvigorate inner-city places of worship by handing them over to migrant communities.

While the church-going population of Ireland continues to decline, non-Irish communities have given a significant boost to congregation figures in the capital.

Several inner-city churches that had experienced sharp declines in congregation figures have since been handed over to migrant communities.

The Catholic church on Dominick Street is now used regularly by the Brazilian community; the Filipino community worships at the church on D'Olier Street; the Lithuanian community uses the church on Westland Row; the Romanian community uses the church on Sean McDermott Street; while members of the Polish community are now regular worshippers at the church on High Street.

The study of disused churches arises out of the Dublin City Heritage Plan, which was a feature of the council's development plan published last year in which the number of churches experiencing falling congregation figures was noted.