Water boarding / skiing in London

I was showing places in London to my friend from India and after we'd finished the London Air Emirates cable car experience, we started walking to see the area in and around Royal Victoria Docland DLR station. That's when my friend spotted a guy carrying a water board. After enquiring, the guy showed us the place where people were water skiing / boarding. The starter course for beginners is £28. It was pretty fascinating. I took a video of a guy waterboarding and a few pictures. One of the pictures shows the prices and other information.

Prices - see picture

Address - Next to Air Emirates cable cars next to Royal Victoria DLR station.