Pollution by wastewater, anion exceeded 27 times, phenol exceeded 3.4 times
On October 7, the Department of Natural Resources and Environment of Dong Nai province publicly announced the results of surface water monitoring in Dong Nai province - phase 7 and phase 8 in 2024.
Accordingly, the results of surface water monitoring in the 7th period of 2024 (from June 3 to June 27) for 18 rivers, 55 streams, and 20 lakes in Dong Nai province and the 8th period of 2024 (from July 23 to July 24) for Dong Nai river, section 3 and La Nga fish farming were summarized.
For streams in the inner city of Bien Hoa city such as Linh stream, San Mau stream, Chua stream, Ba Lua stream, Tan Mai stream and Siep stream, it is found that organic pollution is very high, because they are sources of receiving domestic and production wastewater in Bien Hoa city.
In particular, the Linh stream area has the worst water quality, continuing to detect phenol 3.4 times higher, anionic surfactants 27.3 times higher than the threshold for protecting human health, with an increasing trend compared to the 5th wave.
In addition, the Buong River basin, including rivers and streams in Bien Hoa City, Thong Nhat, Trang Bom and Long Thanh districts, has a decreasing water quality compared to the 5th monitoring period and the same period in 2023.
At 4 monitoring locations on the Buong River flowing through residential areas and industrial zones, water quality has organic and nutritional parameters detected at level C, and microbiology at level D.
The tributaries of the Buong River (Bi Stream, Tu Hoa Sluice, Cau Quan Stream, and Don Stream) are contaminated with organic and nutritional substances. Phenol and heavy metal parameters such as lead and zinc at Tu Hoa Sluice tend to decrease and are not found to exceed the standard threshold compared to previous monitoring periods.
Dong Nai River domestic water supply area tends to improve
For surface water monitoring results in the domestic water supply area of Dong Nai river, section 3:
At Hoa An bridge, water quality in phase 8 tends to improve compared to phase 7 and phase 6, and the same period in 2023.
For parameters serving the classification of water quality and protection of the aquatic environment, most of the values are at level A, the left bank of Hoa An bridge detected heat-resistant coliform, total nitrogen at level C.
For the group of human health protection parameters, only 02/10 parameters were found to exceed the standard (E.Coli exceeded 16.5-39.5 times, iron exceeded 4.0-5.2 times).
At Bien Hoa water plant, water quality in phase 8 improved compared to phase 7, equivalent to phase 6 and the same period in 2023.
Parameters belonging to the aquatic habitat classification and protection group are mostly at level A, except for the total nitrogen parameter at level C.
For the group of human health protection parameters, only 2/10 parameters were found to exceed the standard (E.Coli exceeded 24.5 times, iron exceeded 5.4-6.7 times).
According to the assessment, the water quality at Hoa An bridge is better than at Bien Hoa Water Plant due to lower measured microbial content.
In the fish farming area on the Dong Nai River (Bien Hoa City), the surface water quality in the 8th phase was equivalent to that in the 7th, 6th and same period in 2023, with most parameters at level B, and microbiological parameters and DO at level D.
The Department of Natural Resources and Environment of Dong Nai province has sent a notice to the Department of Agriculture and Rural Development, the Management Board of Industrial Parks, the District People's Committee and Dong Nai Water Supply Company Limited for information and appropriate management solutions.
