Underwater cycling anyone?

I went to have my hair done this afternoon. After a liitle while the hairdresser informed me that she felt sick and hoped that she hadn't caught the sickness bug going round. As my head wasn't in a suitable state to make an excuse and go, I had to stay and risk it!
On the way back home in a blipless state I called at The Mere in Ellesmere which is always good for an emergency shot. I spotted this sign rising out of the water - it must be where cyclists don their nose clips and dive into the water for an underwater spin!
I assume that it's an old sign from the Ellesmere Triathlon though previously the transition area has been on dry land rather than in the water. This new variation is much more interesting!