Mass fish deaths in Korat river probed
Officials in Nakhon Ratchasima's Muang district yesterday speedily removed some 100,000 dead fish from a 3-kilometre-long stretch of the Lam Takong River, and collected fish and water samples to determine the cause of the deaths. The results of tests are
The most likely causes of the incident, which started on Friday and worsened yesterday, were believed to be a factory releasing untreated wastewater, reckless people dumping used engine oil into the river or heavy downpours. Municipality water-quality official Rachan Theerapittayatrakul said the fish died from acute lack of oxygen. He said the dissolved oxygen level was 0.9 milligram per litre – and fish die when the level falls below 2 mg/litre. A large amount of engine oil was found in the river.
Freshwater Fish Research Centre director Charoen Udonkan said the deaths might have been the result of a chemical release, because the water remained clear and many fish that could stand the low-oxygenic environment survived. The centre will soon release 200,000 fish into the area to replace the dead ones.
