Il Hylobos mistero

The clan also went on a lovely walk in the Hylobos wetlands, which have extensive boardwalks to keep your feet dry - see the picture below. But then Mark pointed out to me a system of pipes and faucets running along the boardwalks - see the close-up picture below. Mark suggested the likely use for these faucets. Unlikely to be for watering the vegetation - after all, it’s a wetlands! Can you think of a plausible hypothesis? (Here’s a hint). When you have ideas about what’s going on, press the SOLUZIONE button