Johnson was also chairman of the Gilbert Memorial Committee and a twenty-year member of the Rotary Club of St. John's.
In 1987 Paul had established the Johnson Family Foundation to support the preservation of heritage sites in the province and other charitable projects.
Since that time, many major projects such as the development of "The Lookout" on Signal Hill, the establishment of the Harbourside Park and Gilbert Memorial, the establishment of the Railway Coastal Museum and the Geological Interpretation centre, to name a few, have been realized.
He is renowned for his Grand Concourse Authority, a partnership which brought together the resources of the three levels of government and the university to beautify the capital region and showcase its spectacular heritage and natural assets.
An active member of The Joseph R. Smallwood Heritage Foundation, he was elected co-chairman in 1990.