Prolonged rain and waste caused mass fish death on La Ngà River: official
Changes to the water environment on the La Ngà River in southern province of Đồng Nai have been blamed for the death of nearly 1,000 tonnes of fish this month, provincial officials have said.
Director of the province’s Agriculture and Rural Development Department Huỳnh Thành Vinh said rain lasting from May 15 to early morning of May 16 made waste flow into the river, lowering the dissolved oxygen content in the river’s surface water, killing the fish.
The concentration of ammonia in water river samples was 4-7 times higher than permitted, the nitrite concentration 2-3 times higher than permitted and the COD concentration 3-16 times higher than permitted.