From ANIMAL PEOPLE, September 2003:

BANGKOK–More than two tons of turtles, including 136 of
soft-shelled species and 102 with hard shells, were removed from the
“klongs” (reflecting ponds) of Wat Bovorn in early August 2003 and
hauled to quarantine ponds for evaluation and treatment. Those in
good enough health are to be released at a sanctuary pond in Bang
Sai, reported Laurie Rosenthal of The Nation newspaper.
Mostly purchased from live food markets and dropped into the
klongs by the Buddhist faithful, in the belief that releasing them
would build good karma, the turtles represented a five-year
accumulation.
Draining the klongs and collecting the turtles, many of them
malnourished and diseased, took three weeks.
“Heavy metals and chemicals such as chlorine have affected
the turtles’ livers,” said Nantarika Chansue, DVM, of the
Chulalongkorn University veterinary faculty.
“Many of the hard-shells had round holes on their shells made
from pointed objects,” said Rosenthal.
Explained Nantarika, “People have been taking the turtles
out of the water and trying to kill them for food. Some people also
‘recycled’ them. They took them out of the water and released them
again to make merit,” a perversion of actual Buddhist teaching.
Called the Wang Tao Project, the turtle rescue was funded by
Charoen Pokphand Group executives Wanlop Chiaravanont and his son
Kachorn.