ION - Waterloo Region's Light Rail Transit

[Rainrider22]

For give my ignorance, but can someone explain the middle (or third track) for me please....

No worries!  They just haven't pinned it in place, yet - but it's a pair of guard rails to help prevent a derailed train from crashing into the overpass.  You see the same thing on bridges, too.  Here's a photo of how it will look, from the culvert in Waterloo Park:



Here's what it looks like at Overland Drive, from a little further back (and on a much sunnier day):

Ohhhhh  silly me,   I always wondered about that...Thank you,  Damn I will sleep well tonight now...