The program was a video presentation by Serge Lavoie regarding the St. Thomas Elevated Garden.  Here is a link to YouTube where you can find the video.  2020 National Virtual Symposium - YouTube
The Garden can be accessed off Talbot St.
The railway bridge was built in 1929 as a steel and concrete bridge replacing earlier wooden bridges.  The last train crossed it in 2005 and the tracks were removed in 2010.  Serge noted that Paris and New York have elevated gardens on old railway bridges.
The bridge is 30 feet wide, 855 feet long and 100 feet high.  The group raised $65,000 to buy the bridge and the associated land.  Their objectives were to keep the linear views intact, nothing leaves the site, no motorized vehicles, and it should be handicapped accessible.   It has safety lighting and high safety railings or fencing.
Nature repopulated the area within a year with local, native plants.  The group planted Carolinian native plants, added a Stumpery Garden of huge tree stumps, and permitted the growth of natural weeds and plants.  Monarch Butterflies and raptors such as Red Tailed Hawks are common sights.  On the Garden approaches there is a solid slab maple bench and an adjacent Little Free Lending Library.  
The bridge Garden is divided into 5 zones:  Eastern Board Walk, a Water Garden, a Play area, a Green Garden, and the Western Board Walk.  Six major pieces of art have been donated (metal sculptures).  The Rotary Music Garden has two tuned metal sculptures.
The community has been supportive in every way by helping build the garden, through donations, making videos and planting trees.  The Garden is connected to the Trans Canada Trail.  Art work reproductions are posted on the trail and they plan a 3.5 km linear arboretum of native species trees.
Contacts:  and Facebook:  StThomasElevatedPark