C10 - BOD and concentration of ammonium in rivers of the Republic of Azerbaijan
Is organic matter and ammonium pollution in rivers in the Republic of Azerbaijan decreasing?
Figure 1 - Rivers - Annual mean biological oxygen demand (BOD) and ammonium (2001-2017)
Data sources:
Data was provided from National Environmental Monitoring Department of the Ministry of Ecology and Natural Resources under the ENI SEIS II East project activities
Note: The data series are calculated as the average of annual mean of BOD5 (mg O2/l) (top) and ammonium concentration (mg NH4-N/l) (bottom) for river monitoring sites in the whole of Azerbaijan (left) and in different regions (right) for the period 2001-2017. The number of monitoring sites is given in parenthesis.
Biochemical oxygen demand (BOD) and ammonium are key indicators of organic pollution in water. BOD shows how much dissolved oxygen is needed for the decomposition of organic matter present in water. Concentrations of these parameters normally increase as a result of organic pollution caused by discharges from waste-water treatment plants, industrial effluents and agricultural runoff. Severe organic pollution may lead to rapid de-oxygenation of river water, high concentration of ammonia and disappearance of fish and aquatic invertebrates. Some of the year-to-year variation can be explained by variation in precipitation and runoff.
Over the whole time period there has been a slight increase in ammonium concentration and a slight decrease in BOD (by 32%% and 25%, respectively, if comparing the last three years to the first three years). However, BOD has increased since the minimum level in 2012. For both determinands there was a period with higher levels than the most recent level. This period occurred somewhat later for ammonium than for BOD.
The regional time series patterns are fairly similar to the national patterns. For BOD the levels differed clearly between the regions up until 2010, with the highest levels in Shirvan and Gazakh-Ganja and the lowest in Lankaran-Astara (only represented by two sites). In recent years the results have been more similar. For ammonium concentrations the regions differed most clearly during the peak period (2009-2014), with the highest concentrations found in Gazakh-Ganja.
Transboundary transport, industrial and agricultural production in Azerbaijan, old sewer systems in some areas, and lack of solid waste management in some rural areas have led to an increase in organic pollution up to 2010. The Shamkir and Mingachevir reservoirs along the Kura river were affected by the discharge of waste-water from many settlements in the Kura basin. Over the last 7-8 years, the installation of new modern waste-water treatment plants in the country has reduced organic pollution.
What is the current state of organic matter and ammonium pollution of rivers in the Republic of Azerbaijan?
Figure 2 - Rivers - BOD and Ammonium (2017)
Data sources:
Data was provided from National Environmental Monitoring Department of the Ministry of Ecology and Natural Resources under the ENI SEIS II East project activities
Note: Distribution of river monitoring sites to BOD5 (left) and ammonium concentration (right) classes in different regions in Azerbaijan, based on the average of annual mean concentrations for 2016-2017. The number of monitoring sites per region is given in parenthesis.
The class system is the same as the one used in the EEA indicator WAT 002-EEA indicator WAT 002- Oxygen consuming substances European rivers. See the indicator specification section there for further information.
All river sites had current average BOD below 3 mg O2/l. This is the strictest criterion (for salmonid fish) set by the EU Directive 78/659/EEC. The national maximum allowable concentration is 6 mg O2/l. The Gazakh-Ganja region had the highest proportion of sites with BOD in the class 1.4-2 mg O2/l.
The current ammonium concentration conditions were somewhat poorer than for BOD, with 15% of the sites above 0.2 mg NH4-N/l. However, the national maximum allowable concentration (0.4 mg NH4-N/l) was not exceeded at any of the sites. Comparing to the recommended levels in the EU Directive 78/659/EEC (cyprinid fish: 0.16 mg NH4-N/l; salmonid fish: 0.03 NH4-N/l), 39% of the sites had average concentration above the upper threshold, and no sites were below the lower threshold. The sites with the highest concentrations were found in the Shirvan, Gazakh-Ganja and Lankaran-Astara regions. In Guba-Khachmaz no sites had ammonium concentration above 0.16 mg NH4-N/l.
Indicator specification
Indicator definition
The level of oxygen concentration in water bodies, expressed as biochemical oxygen demand (BOD) - which is the amount of dissolved oxygen required for the aerobic decomposition of organic matter present in water - and the level of concentrations of ammonium (NH4/N-NH4) in rivers.
Units
The annual average BOD after five days of incubation (BOD5) at 20 degrees Celsius is expressed in mg of O2/litre; the ammonium concentration is expressed in mg of N/litre.
Rationale
Justification for indicator selection
Large quantities of organic matter (microbes and decaying organic waste) can result in reduced chemical and biological quality of river water, impaired biodiversity of aquatic communities, and microbiological contamination that can affect the quality of drinking and bathing water. Sources of organic matter are discharges from waste-water treatment plants, industrial effluents and agricultural runoff. Organic pollution leads to higher rates of metabolic processes that demand oxygen. This could result in the development of water zones without oxygen (anaerobic conditions). The transformation of nitrogen to reduced forms under anaerobic conditions, in turn, leads to increased concentrations of ammonium, which is toxic to aquatic life above certain concentrations, depending on water temperature, salinity and pH.
The water resources of Azerbaijan are limited in comparison with other countries in the South Caucasus and are only 15 per cent of all water resources in the region. The sources of surface water resources of the country are rivers, lakes, water reservoirs and glaciers. The dependency ratio of Azerbaijan to upstream countries is around 67-70% of its total renewable freshwater resources. . Azerbaijan is a water-scarce country facing severe water stress conditions, with a long-term average annual water exploitation index (WEI) of greater than 30.5 % (WEI = 41.2 % in 2017) (See C2 and C3 indicators for more detailed information).
There are 21 transboundary rivers in the country, and most of them are in the basins of the Kura and Araz rivers. The Kura and Araz basins are located in three and four countries, respectively.
Following the accession to the UNECE Helsinki Convention on the Protection and Use of Transboundary Watercourses and International Lakes, water quality control activities in the Kura and Araz rivers, which are the main transboundary rivers, have been set up in accordance with international standards.
Taking into account the pollution level of water already in the upstream countries, monitoring of water quality in Azerbaijan is crucially important. With that purpose, analytical research laboratories were established in the Qazakh and Beylegan districts, with the aim of conducting monitoring activities in the Kura and Araz rivers and their transboundary tributaries.
Scientific references
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Council Directive 91/271/EEC of 21 May 1991 concerning urban wastewater treatment
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Directive 2000/60/EC of the European Parliament and the Council of 23 October 2000 establishing a framework for Community action in the field of water policy (Water Framework Directive) http://ec.europa.eu/environment/water/waterframework/index_en.html;
Policy context and targets
Context description
National policy context
The “State program of socio-economic development of regions of the Republic of Azerbaijan for 2019-2023” states the aim to protect the environment and ensure clean water. The “Water Code of the Azerbaijan Republic” describes the principles for management, monitoring, use and protection of water bodies. Article 81 states that “All waters (water objects) must be protected and defended of pollution, contamination, exhaustion, which may bring damage to the health of population, and also may cause decrease of fish reserves, worsening of conditions for water supply and other unfavourable phenomena as a result of changed physical, chemical, biological characteristics of waters, decrease of their abilities for natural self-cleaning, violation of hydrologic and hydro geologic regime of waters”. Article 78 sets limitations on the discharge of waste-water.
Currently, the Strategy of the Republic of Azerbaijan for integrated water resources management is under development. The National Water Strategy (NWS) is aimed at the development of water resources management and water protection as well as water supply and sanitation in Azerbaijan to better meet both international and EU level standards and objectives. The draft Strategy contains goals, which are divided into short-term (6 years), medium-term (18 years) and long-term goals.
Joint work regarding the implementation of “Targeted Indicators” with the relevant state bodies are going on according to the Protocol on Water and Health. In this regard, by the provisions of the Water Convention and its Water and Health Protocol, Targeted Indicators of the Republic of Azerbaijan were developed and approved by the Joint Order of the Ministry of Health and the Ministry of Ecology and Natural Resources.
International policy context
The Convention on the Protection and Use of Transboundary Watercourses and International Lakes (Water Convention) aims to ensure the sustainable use of transboundary water resources by facilitating cooperation. The Water Convention strengthens transboundary water cooperation and measures for the ecologically-sound management and protection of transboundary surface waters and groundwater.
Targets
National targets
The main target and national water policy is to ensure that throughout country, a sufficient quantity of good-quality water is available for people's needs and for the environment. The national maximum allowable concentrations are:
BOD: 6 mg O2/l
Ammonium: 0.5 mg NH4/l (0.4 mg NH4-N/l)
International targets
The UN Sustainable Development Goal 6 target 6.3 aims to achieve, by 2030, improve water quality by reducing pollution, eliminating dumping and minimizing release of hazardous chemicals and materials, halving the proportion of untreated wastewater and substantially increasing recycling and safe reuse globally
Related policy documents
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State program of socio-economic development of regions of the Republic of Azerbaijan for 2019-2023
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The UNECE Convention on the Protection and Use of Transboundary Watercourses and International Lakes
Methodology
Methodology for indicator calculation
Following joining the UNECE Convention on the Protection and Use of Transboundary Watercourses and International Lakes, water quality control activities in the Kura and Araz rivers, which are the main transboundary rivers, have been met by international standards. Operational monitoring has been implemented in both rivers based on the guidelines on "Transboundary Watercourses and International Lakes Monitoring and Evaluation", prepared by a team of qualified UN experts.
The river monitoring programme comprises 47 river monitoring sites. Annual time series for each site are calculated by averaging the values for individual samples per year. Aggregated time series are calculated as the average of the individual annual time series. Only time series that are complete after gap filling are included in the aggregated time series. This is to ensure that the aggregated data series are consistent, i.e. including the same sites throughout the time series. In this way assessments are based on actual changes in concentration, and not changes in the number of sites. The time series were aggregated for the whole country and per region (Gazakh-Ganja, Guba-Khachmaz, Lankaran-Astara and Shirvan).
For the present state analysis, the monitoring sites were assigned to different concentration classes, based on the average of annual mean concentrations for 2016-2017. All sites with data from 2016-2017 were included in the analysis, independent of the number of years with data within the time period. The results were split on the different regions.
Methodology for gap filling
Gaps of up to three years are filled by linear interpolation. At the beginning and end of the time series values are extrapolated by copying the first or last value, respectively, for up to three years. Time series with more than three consecutive years missing within the selected time period are not included.
Methodology references
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ISO 5815-2: 2003 Environmental protection and environmental management. Analytical control and monitoring. Water quality. Determination of biochemical oxygen consumption after n days (BODn). Part 2. Method without diluting samples.
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ISO 6777:1984 - Water quality — Determination of nitrite — Molecular absorption spectrometric method. Specifies a method for potable, raw and waste water. A list of effects of other substances on the result is given in the annex. As standard nitrite solutions may become unstable, the concentration of these solutions has to be checked by a given procedure.
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EEA, 2005. EEA core set of indicators guide. EEA Technical report No 1/2005, ISBN 92-9167-757-4, Luxembourg.
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UNECE, 2018. Guidelines for the Application of Environmental Indicators, Description of C10. Biochemical oxygen demand (BOD) and concentration of ammonium in rivers.
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UNECE, 2018. Guidelines for the Application of Environmental Indicators, Glossary of terms – C10. Biochemical oxygen demand (BOD) and concentration of ammonium in rivers.
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UNSD and UNEP, 2013. Questionnaire 2013 on Environment Statistics. United Nations Statistics Division and United Nations Environment Programme, Questionnaire 2013 on Environment Statistics, Section Water.
Uncertainties
Methodology uncertainty
No methodological uncertainty has been specified.
Data sets uncertainty
No uncertainty has been specified.
Rationale uncertainty
No uncertainty has been specified.
Data sources
Data was provided from National Environmental Monitoring Department of the Ministry of Ecology and Natural Resources under the ENI SEIS II East project activities