This is only one Prefecture. The April festival of Songkran Thai New Year in Thailand looks very similar except it is 3 days and nationwide. Traffic police have their radios and guns covered in cling film/saran wrap. Youths drive around in pickup trucks with buckets/pails, which they refill from an on-board water barrel, dousing "unsuspecting' passers-by at 40kph. Every bar in the kingdom is full of Super Soakers and it is impossible to stay dry. The “Not Amused” crowd usually book those 3 days at secluded resorts. Small children in rural areas have hand pumps, which resemble an old fashion bicycle pump, these when used in conjunction with a garbage can full of water are very effective.
Lookout. Some municipalities ban what they call "spaghetti" tops but school girls up to and including high-school still wear their tight white uniform shirts and are a favorite target.
http://www.pattaya-at-night.com/songkran/
www.beachpatong.com/photogallery/songkran/
http://www.thailandlife.com/songkran.htm