All rivers, streams and lakes have special spirits living in them ; some of these are good. and some are bad. One of the worst water spirits is the phi ha . which brings epidemics. Cholera and other water-borne diseases are attributed to the evil doings of this spirit. In order to prevent the phi ha from spreading disease. shrine in his honor have been built along the chao phraya and other rivers. It is forbidden to throw refuse into the river near one of these shrines, unless permission is first requested from the spirit and appropriate offerings are made. Even fishing is not allowed near the shrines. for all the fish in the area belong to the spirit.