Celebrate Good Times... (c'mon?)

A UAE diplomat was being held captive in Iraq by some new Former-Street-Gang-Turned-Terrorist-Outfit. To cut a long story short, he was released and upon his release his local municipal council had the following celebration:

Thrilled with the good news, the Municipality of Dibba Al Hosn watered all streets surrounding the diplomat's house. Meanwhile all the festive decorations were undertaken by the local Theatrical Arts Association. A big spontaneous procession comprising friends, neighbours, and compatriots were also out there in large numbers in anticipation of Naji's much-awaited return.

I mean, it is lovely to see that the council has this spirit of jubilation, but why are they watering the streets?

Answers on the back of £50 notes please.