The Catholic population in the area grew gradually through this time, until in 1950 Bishop Ryan of Hamilton reconstituted St. Thomas as a separate parish and appointed Fr. Joseph P. Cremmen as the first pastor. Since then the growth of the parish has paralleled the growth and development of the Town of Waterdown and surrounding area.
Around 1990 Waterdown’s Catholic community again found itself growing beyond the capacity of the existing church building and began planning for a new home. Completed and dedicated in 2005, St. Thomas the Apostle Church on Centre Road reflects the dynamism of the Catholic faith in the 21st century. Designed to meet the needs of the faithful, not just in terms of worship, but to address the growing desire for catechesis, community social life, youth and family ministry, and to provide a barrier-free, fully accessible facility.