С.10. Biochemical oxygen demand and concentration of ammonium in rivers

download the file in Excel format for 2005–2022

Brief description:

Biochemical oxygen demand (BOD5) in rivers is an integral indicator of the contamination of surface waters and reflects the amount of dissolved oxygen required by organisms for the aerobic decomposition of organic matter present in water. In Belarus, BOD5 water quality indicator is not more than 3 mg O2/litre for surface water bodies used for breeding, fattening, wintering, and migration of fish species of salmon and sturgeon; is not more than 6 mg O2/litre for other surface water bodies;

Ammonium is one of the main river pollutants. The limit value for the concentration of ammonium is set as 0.39 mg of N/litre; The indicator is presented in the context of selected rivers by surveillance stations


Biochemical oxygen demand and concentration of ammonium ions in rivers

 

Annual average biochemical oxygen

 demand (BOD5), mg of О2/litre

Concentration of ammonium ions

(NH4/N-NH4), mg of N/litre

2010

2022

2010

2022

Berezina

1.82

2.77

0.86

0.34

Viliya

2.53

2.07

0.47

0.07

Dnieper

2.15

2.07

0.41

0.31

Western Dvina

2.10

2.21

0.45

0.18

Western Bug

2.88

3.86

0.35

0.14

Mukhavets

2.43

2.61

0.81

0.31

Neman

2.36

2.56

0.43

0.16

Pripyat

2.46

2.69

0.50

0.11

Svisloch

2.90

2.26

0.82

0.34

Sozh

1.53

2.07

0.33

0.31



Methodology:

The annual average biochemical oxygen demand after five days of incubation is estimated on the basis of information on surface water samples taken and tested at each surveillance station of the state surface water monitoring network;
The concentration of ammonium is estimated on the basis of information on surface water samples taken and tested at each surveillance station of the state surface water monitoring network.



Data source:

The National Environmental Monitoring System;
The data producer is the Ministry of Natural Resources and Environmental Protection of the Republic of Belarus.



Relevance of the indicator:

The indicator provides a measure of the state of rivers in terms of biodegradable organic load and ammonium