It's a blessing, didn't you know!?! The Lao New Year also includes the Water Throwing Festival (boon hoht nam). People will literally be drenching you with water from buckets to water guns to cups. It's the one time of the year where it's ok to do this even to a complete stranger so beware!
Traditionally, the act of hoht nam is considered a blessing to the person you're getting all wet and a symbolic gesture for them to wash away all the bad things in their lives and to invite only good things in the new year.