Day 6.089: L'eau - an answer!

After the mystery sign of Day 6.085, I was excited to see another similar one the next day - this time with some explanatory text.

Finally we would know - is it about bicycles (Exile #3's guess), the scales of justice (mine), movable picnic tables (Dad), clackers (A)?

I moved closer to see what it said...

Hmmm - perhaps it would remain a mystery - albeit one now possibly related to swimming pools.

Except, wait - what's that below the sign...?

Ah - the same pipework as before - as noticed by Tall Guy - and could those "balls" actually be water outlets positioned at the same jaunty angle as the real ones?  I believe we have a winner - Montreal's unique fire hydrant signage!