Q:

Convert IGLD85 to CGVD28 - Vertical Datums

I have water level data for the Toronto Harbour that states, "74.200 metres above IGLD 1985"
I also have land elevation data around Toronto that uses the Geodetic Vertical Datum of 1928 (CGVD28)
To relate the two datasets I assume I need both sets of data using the same vertical datum. 
How do I convert IGLD85 to CGVD28 for the area around the Toronto Harbour?

A:

I just needed to find a benchmark in my geographic region of interest that had both of my vertical datums. That info is found here. 

