Point source pollutants are specific objects related to a specific location (in the field of water e.g. “pipe endings” of water treatment plants, i.e. waste water discharges, waste water discharges of industrial companies, storm water discharges, etc.) that are used to discharge waste water and pollutants into the environment. For example, cattle-sheds, manure piles or other similar clearly definable objects which discharge pollutants into the environment.
According to the Water Act, a permit for the special use of water is required for the discharge of waste water into the environment. Holders of this permit submit an annual report of their water usage, where they include, among other things, their pollution loads. Based on the reports presented by the permit holders, the Environment Agency prepares a of water usage in Estonia.
This indicator provides annual quantities of pollutants discharged into the environment with waste water, mainly into bodies of surface water, i.e. the summarised pollution load for the entire Estonia. Only waste water loads reported based on a water or another environmental permit have been summarised, therefore the actual pollution load may be slightly heavier. Pollution loads have been provided in thousands of tons per year.
The pollutants BOD7, TN and TP presented on the graph are key indicators of waste water, which are used to assess the status and water quality of water bodies:
- BOD7, i.e. biochemical oxygen demand indicates the amount of oxygen needed for microbes to decompose organic matter in one litre of water within 7 days. Therefore, the waste water discharged into a water body is likely to decrease the oxygen content of the water, in turn affecting its water organisms;
- TN, i.e. total nitrogen is a plant nutrient which causes eutrophication of water bodies;
- TP, i.e. total phosphorus is a plant nutrient which causes eutrophication of water bodies.
Pollution loads must especially be reduced to decrease and prevent the eutrophication of water bodies which serve as receiving bodies of water. Eutrophication means the excessive growth of plants and phytoplankton caused by the over-abundance of nutrients (mainly phosphorus and nitrogen). In a eutrophic water body, some species may start to flourish at the expense of others, causing decreased biodiversity of biotic communities. The excessive growth of plants is accompanied by decomposition processes which cause accumulation of organic matter, oxygen depletion in water layers near the bottom, and a general decrease in water quality, which in turn has a negative impact on the rest of the water organisms. Therefore, to maintain the good status of our water bodies, we need to limit the pollution load of nutrients caused by humans.
In the past few decades, the pollution loads have decreased significantly in Estonia. On the one hand, this was caused by termination of the large-scale industry of the Soviet Union and a decrease in population, on the other hand, large investments have been made into building and upgrading water treatment plants. In 2000–2016, nearly 1.09 billion euros were invested into the drinking and waste water infrastructure.
Over a long timeline (24 years in total), the pollution load of TN has decreased by 5 times, TP by 12 times and BOD7 by 18 in Estonia. It seems that the minimum level has been achieved and the loads have remained stable over the past 4 years. However, considering Estonia’s small surface area, the national statistics may be influenced by the opening or closure of even one large factory.
Abstraction shows the pressure of human activity on the environment. Pursuant to the Water Act, a permit for the special use of water is required if groundwater is abstracted in a volume of more than 5 m3 per day or water is abstracted from a surface water body in a volume of more than 30 m3 per day. This indicator shows the abstraction of groundwater or surface water reported in the annual reports of persons with a permit for the special use of water (including water companies) in millions of cubic metres per year. As a permit for the special use of water is not required from all persons abstracting water, actual abstraction is probably more extensive in Estonia. For example, individual residents with a personal well are not included in the abstraction calculations, as their abstraction is below the threshold mentioned.
Approximately 81% of the total abstraction in Estonia is made up by the cooling water of power plants in Ida-Viru County. Cooling water is mainly abstracted from the Narva river and discharged back into the river after the cooling processes (up to 1.3 billion cubic metres per year). The chemical composition of the water does not change during the cooling process (no purification needed), however, the discharged water’s temperature might be slightly higher than that of the river. As the power plants are located downstream from each other, the cooling water is also used twice – the Eesti power station located upstream discharges its cooling water back into the Narva river which is in turn used for abstraction by the Balti power station.
Production of electricity and the use of cooling water related there to are largely dependent on the exchange price of electricity, which is why the quantities of cooling water vary by years. The proportion of cooling water from the annual average drainage of the Narva river is 8–20%, on average 13%.
Another larger abstraction type (proportion around 11%) is water pumped out of mines and quarries (see figure Abstraction in 2016). These quantities are largely dependent on rainfall, as the more rainfall there is in a year, the larger the quantities of drained mine and quarry water are, where the rainfall that has soaked into the ground has mixed with groundwater.
Therefore, the rest of the abstraction of ground- and surface water only makes up 8% of the total abstraction. Compared to cooling water and water from mines, the quantities of both abstracted ground- and surface water have been more stable. The abstraction of surface water has slightly increased over the recent years, but the abstraction of groundwater has remained at approximately 46 million cubic metres per year. A lower resource fee, as well as a higher threshold in granting permits are probably behind the consumption of surface water. Considering the recovery time of water resources, the more sustainable use of groundwater is very welcome.
A more detailed overview of the annual abstraction of ground- and surface water in Estonia can be obtained from theon water usage and on the groundwater balance.
The water use indicator shows where and how much the abstracted water is used. This indicator shows the water use reported in the annual reports of persons with a permit for the special use of water (including water companies) in millions of cubic metres per year.
Groundwater and surface water are not distinguished in water use; water use is presented as a total by fields. The consumption types distinguished in of water use include use of water intended for domestic purposes, industry (industrial water use) and cooling water of industry, agriculture, irrigation, energy (additionally, cooling water of individual power plants, see the indicator “abstraction of ground- and surface water”), and other abstraction. The graph provided indicates changes in the three most significant types of water use (water intended for domestic purposes, industry, agriculture) over time. Cooling water which makes up the largest part of abstraction is used as cooling water of power plants (approximately 1.4–1.5 billion cubic metres per year), which is why it has not been provided in this graph.
Over the past 16 years, industrial water use has decreased from approximately 44 million cubic metres to approximately 29 million cubic metres (decrease of 35%). The lowest industrial water use was in 2009 (24 million cubic metres) – this probably reflects the impact of the economic crisis. However, over the past five years, industrial water use has remained stable at approximately 28 million cubic metres per year.
Agricultural water use (including drinking water for animals) has remained stable at 4–4.7 million cubic metres per year. In addition to agricultural water use, water use records are also kept on the quantities of irrigation water which amount to approximately 5% of agricultural water use (0.5 million cubic metres per year). As the quantities of irrigation water are small, these have not been indicated in the graph mentioned.
According to the Water Act, water intended for domestic purposes means all water intended for drinking, cooking, food preparation or other domestic purposes, regardless of its origin and whether it is supplied from a distribution network, from a water tank, or in bottles or containers.
According to the 2016 data of the Health Board, approximately 87,6% of the residents of Estonia use water from the public water supply. Water use reports are not submitted by individual consumers whose abstraction is small (groundwater is abstracted in a volume of less than 5 m3 per day, water from a surface water body in a volume of less than 30 m3 per day) and those who do not need a permit for the special use of water due to this (approximately 14% of residents) and are thus not included in the statistics.
In 26 years, the number of people has decreased by approximately 186 000 (decrease by 12%) and the quantities of consumed water intended for human consumption by approximately 2.5 times – from 104 million cubic metres to approximately 42 million cubic metres per year. On the one hand, this is due to the reconstruction of public water supplies, which has reduced leaks to a significant extent, on the other hand, the increase in water price has urged consumers to use water more economically.
Per one resident, the consumption of water intended for human consumption has decreased up to 2.2 times in a couple of decades – from 68.8 to 32 cubic metres per year. Over the past five years, the consumption of water intended for human consumption has remained stable at 30–32 cubic metres per year, i.e. 83–86 litres per 24 hours (approximately 8 buckets of water per person per 24 hours). This is approximately 2 times lower than the average indicators of the European Union. According to the of the European Environment Agency, an average urban resident of the European Union consumes approximately 144 litres per 24 hours (14 buckets per 24 hours).
By counties, the differences in the use of water intended for human consumption per person are approximately threefold – the lowest consumption of water intended for human consumption takes place on the islands, the largest consumers are Ida-Viru, Pärnu and Harju Counties. This is most likely rather due to statistical differences stemming from the construction of the public water supply (individual wells in low-density areas, public water supplies in high-density areas) and number of persons submitting water use reports in different counties.
The main objective of the Water Framework Directive adopted in 2000 was that by 2015, all water bodies (rivers, lakes, coastal waters, groundwater) have reached at least good environmental status. Unfortunately, this objective was not reached in neither Estonia nor Europe and currently, objectives are being set for 2021 and 2027.
This indicator shows the proportion of bodies of surface water that have reached at least good ecological status in Estonia. In addition to the ecological status, the chemical status of water bodies is also assessed (concentration of hazardous pollutants in the water environment), however, the chemical status was not considered for this indicator due to the lack of data. This is a status indicator which forms the basis for planning water protection measures. with a six-year term are prepared for achieving the good status of water bodies and in the course of implementation of these plans, measures are implemented for improving the status of water bodies.
A total of 750 bodies of surface water have been distinguished in Estonia: 644 for water courses, 90 for lakes, and 16 in coastal waters. All these should have achieved good status by 2015 (goal 100%).
Ecological status primarily means the status of aquatic biota (water plants, algae, benthic fauna, plankton, fish) and other factors affecting this (hydromorphology, water quality, concentration of pollutants in the water, etc.) and their disturbance due to human activity (). Ecological status is described by using the following quality classes:
- very good – changes caused by human activity do not exist or are insignificant;
- good – changes in biological indicators caused by human activity are small, the hydromorphological characteristics of a water body have not been changed in a way that would affect the biota, no obstructions to the current exist in rivers (e.g. dams);
- moderate – changes in biological indicators caused by human activity are moderate compared to natural reference water bodies (greater than in a water body in good status), a water body may, for example, be affected by land improvement or obstructions to the current may occur;
- poor – biological indicators vary greatly from the reference conditions; a great proportion of the normal biotic communities is missing;
- bad – biological indicators greatly deviate from the reference conditions or biota does not exist.
Assessments of the ecological status of a water body are mainly based on biological indicators and a status assessment is given based on the biological quality element in the worst status.
The ecological status of bodies of water has been assessed since 2010. As this is done based on monitoring data, there was insufficient data by the first assessment period, due to which the status assessments were largely based on expert opinions. Later, when the monitoring activities expanded and the amount of data increased, it appeared that the expert opinions may have been overly optimistic and actual measurements did not confirm the initial expert assessments of the status of water bodies. This is why the trendline depicting changes in statuses is also in decline on the graphs. The second reason is changes in assessment scales. For example, the comparative tests of status assessments carried out on the European scale revealed that our local assessment system of coastal waters needed to be made stricter.
The status of water bodies is assessed based on monitoring data which is usually carried out with a six-year rotation cycle. This means that most of the bodies of water are observed every six years. Only a small proportion of the bodies of water (reference water bodies) are observed every year or with a three-year rotation cycle. Outcomes of the previous observation year are used in calculating the indicator. This means that if a body of water was previously observed, for example, in 2013 and a status assessment was given based on these data, then the 2017 consolidated assessment of water bodies includes the 2013 status assessment for that body of water. Approximately 60 water courses, 30 lakes and six coastal bodies of water are observed annually. Observation and assessment outcomes of the previous years are used for all other bodies of water.
Mainly due to the aforementioned reasons (new monitoring outcomes do not confirm the earlier expert assessments of the status, the assessment system and environmental norms have changed), the status assessments of bodies of surface water have become more negative. Water courses are the only bodies of water where the goal has been achieved for 58%. Pursuant to the 2017 data, only 46% of lakes are in very good or good status.
More information regarding the statuses of bodies of water can be seen on the web page of the Environment Agency: https://www.keskkonnaagentuur.ee/et/eesmargid-tegevused/vesi/pinnavesi/veekogumite-seisundiinfo and https://www.keskkonnaagentuur.ee/et/veekogumitekaardid.
This indicator shows the assessment of the ecological status of Estonia’s bodies of coastal waters with relation to the goal (at least good status). Principles of assessing the ecological status have been provided by the indicator Status of water bodies.
This indicator has been calculated as follows: on the five-point scale of ecological status assessment, 1 point refers to very good, 2 points to good, 3 points to moderate, 4 points to poor and 5 points to bad status. For measuring the distance from the target, the target value (good status = 2 points) is divided by the value measured in the course of an actual monitoring (e.g. moderate = 3 points). The closer the outcome is to number one, the closer the achievement of the target is. If the value is above one, the target has been achieved and exceeded. The graph considers the ecological status of all 16 bodies of coastal water as an annual average (the points of the status assessments of the water bodies have been summarised by years and divided by 16 and then the target “2” has been divided by the calculated average).
The Baltic Sea is considered one of the seas most affected by human activity in the world. Considering the slow processes occurring in the sea and earlier pollution, which has accumulated in the sea, reaching the good status of coastal waters is most likely not possible in the next decade.
Status assessments of the previous years indicate a stable moderate ecological status (especially with regard to phytoplankton indicators and excessively high concentration of nutrients) and only a few individual water bodies have been classified to be in good status in some years. Pursuant to the data included in water management plans prepared as at 2017, only 19% of the surface area of coastal waters was in good status (three bodies: Narva-Kunda, Hara and Kihelkonna coastal waters). The following graph illustrates reaching the target of bodies of coastal waters (as at 2017 water management plans):