Mooragh Park interactive fountains.

Mooragh Park is an old Victorian pleasure park with a large boating lake, complete with its own island. In the past the Isle of Man used to be a very popular British holiday destination, and this is one of the legacies of that era.
By far the most intriguing technical feature is this interactive water-play area which is usually busy with families enjoying getting, or narrowly avoiding getting soaked. It was actually really unusual to see it so quiet (Sunday lunchtime on a bleak day) so I took the opportunity to make a video without the risk of looking like some weird kiddie stalker.
As far as I know the water for the fountains comes from the water main to avoid the hygiene issues of recycled water. There's no shortage of water on the Isle of Man and the amount the water feature uses is nothing compared to many buildings or lawn/garden irrigation systems. The water seems to drain directly into the lake. I'm not sure what actually controls the water flow as some of the jets seem to build up slowly, suggesting a motorised valve.
There are robust buttons which I would guess are piezo pressure sensors as they are metal and have no physical movement. They activate different areas of the play area and if not in use there are just random bursts of fountain activity.
This attraction is really popular with families and groups of elderly people, just because it creates a good happy ambience. It's one of those things that just turned out to be a huge success. The fact that there is a Costa coffee bar right next to it also keeps the parents happy with their coffee's while their kids get soaked in the fountains.

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