Water is one of the most important natural resources and its use relates to all human activities and natural processes. However, water as a resource is often supplied freely without any consideration for its self-purification capacity. Freshwater quality improvement and protection against eutrophication are among the main priorities in Latvia’s environmental policy. To ensure its rational use and long-term protection, water has been defined as a important national asset[1].

Water quantity:

Latvia is one of the richest states in the world in terms of fresh water resources, given the size of the country’s population.

Freshwater resources far exceed present and future requirements for water consumption. In Latvia, the Water Exploitation Index (WEI) is one of the lowest in the European Union. Moreover, it has decreased from 0.013 in 1990 to 0.007 in 2005, due to economic and institutional changes and water saving and water efficiency measures.

• CSI 018 Use of freshwater resources

Water quality:

• The eutrophication of inland surface water and marine water - particularly in the southern part of the Gulf of Riga - is a major environmental     problem
• In general, the nitrogen concentration in rivers is increasing slightly
• There is no common trend for the annual average phosphorus concentration in rivers; it varies between rivers and depends on the different socioeconomic, climatic and hydrological conditions in each river basin district
• The concentration of oxygen-consuming substances in rivers is low and this generally indicates good water quality.

Ecological quality of water bodies

Figure 1: Ecological quality of inland surface water bodies in Latvia

Source: Latvian Environment, Geology and Meteorology Centre

River Basin Environmental Reports (in Latvian) River Basin Management Plans (in Latvian)

The territory of Latvia is sub-divided into the catchment areas of four large rivers to create the Daugava, Gauja, Venta and Lielupe river basin districts.

According to the information included in the first river basin management plans, 51 % of surface water bodies are currently considered to be of high or good ecological quality (Table 1). The main cause of inadequate surface water quality is eutrophication due to pollution from point and diffuse sources, morphological changes in rivers and an influx of biogens from neighbouring countries via transboundary watercourses.

Table 1: Ecological quality of inland surface water bodies in Latvia

Source: Latvian Environment, Geology and Meteorology Centre

Nutrients in the largest rivers

Figure 2: Annual average concentrations of nitrogen in river estuaries

Source: Latvian Environment, Geology and Meteorology Centre

Since the beginning of the 1990s the annual average concentration of nitrogen in rivers has decreased and does not exceed 2 mg/l in Daugava, Gauja and Venta. In Lielupe, the concentration of nitrogen is higher due to intensive agriculture activity in this region. In 2007, the average nitrogen concentration in Lielupe exceeded 6 mg/l. However, despite a variability in the overall average nitrogen concentration from year to year, the recent trend indicates a small increase in nitrogen concentrations in all rivers.

In Lielupe, the annual average concentration of total phosphorus has changed significantly compared with other rivers. This is partly explained by climatic and specific hydrological conditions in the catchment area.

Figure 3: Annual average concentrations of phosphorus at river estuaries

Source: Latvian Environment, Geology and Meteorology Centre

Point and diffuse pollution sources have the most significant impact on the ecological quality of inland water. Transboundary pollution also affects freshwater quality. More than 50 % of the total run-off from rivers in Latvia originates in other countries and contains significant amounts of pollutants, particularly nutrients. The largest rivers receiving pollution from neighbouring countries are the Daugava, Lielupe and Venta.

It is estimated that more than 70 % of the total nitrogen and more than 40 % of the total phosphorus inland load is caused by various human activities – e.g. waste water discharge or run-off from agricultural land and forests. The agricultural sector generates the largest proportion of nitrogen discharge and the main source of phosphorus is municipal and industrial waste water.

CSI 020 Nutrients in freshwater

Oxygen-consuming substances in the largest rivers

Figure 4: Pollution by oxygen-consuming substances at river estuaries

Source: Latvian Environment, Geology and Meteorology Centre

In recent years, the annual average concentrations of BOD₅ have decreased in Venta and Daugava, but this trend has not been observed in Lielupe and Gauja. BOD₅ values observed during the period 2001–2008 are generally less than 2 mg O₂/l and are typical of good quality water. Values between 2 and 2.5 mg O₂/l indicate only slightly polluted surface waters.

CSI 019 Oxygen-consuming substances in rivers

Water quantity:

Pressures on freshwater quantity

• The total amount of water abstraction has decreased; the consumption of surface and groundwater has stabilised in recent years
• The amount of abstracted surface water has decreased
• The amount of abstracted groundwater has not changed significantly.

Figure 5: Freshwater resources and use

Source: Latvian Environment, Geology and Meteorology Centre

Figure 6: Groundwater resources and use

Source: Latvian Environment, Geology and Meteorology Centre

The total amount of water abstraction is falling. Since 1991, abstraction of both ground and surface water has decreased twofold. This trend is explained by the stabilisation of industrial activity following a significant drop in production in the 1990s. It has also been boosted by the modernisation and reconstruction of water management systems in cities and small towns and the installation of water meters which motivate water-saving practices in industry and in households. In 2007, 46 % of water consumption was for municipal use; 26 % for agriculture and 18 % for industry.

Figure 7: Water consumption in economic sectors

Source: Latvian Environment, Geology and Meteorology Centre

Traditionally, groundwater is the main source of the drinking water supply, both in rural areas and in cities, but problems arise due to the uneven distribution of resources and consumers. Furthermore, increased natural content of iron, manganese, sulphates and other elements at certain locations results in poor-quality drinking water. Surface water is only used in Riga for the drinking water supply.

Water quality:

Pressures on freshwater quality

• The total amount of wastewater discharge from point sources is not increasing
• The total amount of nitrogen discharged in surface water together with waste water is not increasing
• The total amount of phosphorus discharged in surface water together with waste water is decreasing

Between 1991 and 2000, the total amount of waste water discharge decreased drastically. After 2000, the total waste water discharge stabilised and is now around 200 million m³ annually. Recent trends indicate that the proportions of untreated waste water and treated waste water that do not comply with the designated treatment standard are decreasing.

 CSI 024 Urban waste water treatment

Figure 8: Total wastewater discharge, 1991– 2007

Source: Latvian Environment, Geology and Meteorology Centre

Figure 9: Number of wastewater treatment plants, 2000–2007

Source: Latvian Environment, Geology and Meteorology Centre

The positive developments in waste water treatment have been brought about by the need for Latvia to meet its obligations under EU Directive 91/271/EEC on urban waste water treatment. These include: the treatment of collected waste water before discharge and improvement of waste water treatment technology in all agglomerations with a population equivalent of over 2 000. Following its accession to the EU, Latvia had three transitional periods during which to meet the obligations of EU Directive 91/271/EEC on urban waste water treatment:

(i)      for agglomerations with a population equivalent of less than 100 000: until 31 December 2008 (two agglomerations);

(ii)    for agglomerations with a population equivalent of 10 000–100 000: until 31 December 2011 (24 agglomerations);

(iii)    for agglomerations with a population equivalent of 2 000–10 000: until 31 December 2015 (62 agglomerations).

The national programme Development of water service infrastructure in agglomerations with a population equivalent below 2000 has made a significant contribution to the renovation and reconstruction of waste water treatment plants and centralised sewage collection systems in small towns. At the end of 2008, projects completed within the framework of this programme provided compliant waste water treatment in 101 populated areas.

Nutrient load from point sources

Source: Latvian Environment, Geology and Meteorology Centre

Since 2000, total nitrogen discharge has been comparatively stable, with no tendency to increase. Meanwhile, the total phosphorus load from point sources continues to decrease. It appears that diffuse pollution sources are having an increasing impact on freshwater quality and climate change is a significant contributing factor in this process.

Priority areas in relation to water quality and resources, as set out in the Environmental Policy Strategy 2009–15 are:

• eutrophication of inland surface water (rivers and lakes) and marine water, particularly in the southern part of the Gulf of Riga
• transboundary pollution in international river catchment basin
• unsustainable water use due to an inadequate and outdated water supply network.

In accordance with national guidelines and Water Framework Directive river basin management plans, the indicators used to characterise the effectiveness of national environmental policy will be:

• a decrease in water consumption (per capita annually) from 85 m^{3 to} to 80 m³
• a decrease in surface water abstraction from 104 million m³ to 99 million m³
• a decrease in groundwater abstraction from 108 million m³ to 103 million m³
• up to 79 % of water bodies rated as high and good quality (for inland surface waters)
• an increase in the proportion of the population provided with centralised waste water collection and treatment services (up to 62 % of the total population).

However, once available, the results should be carefully analysed. At present, due to the complicated economical and financial situation, it is difficult to reliably forecast future trends in water quality and resources. There is no clear picture of how the situation will be after structural changes affecting the main driving forces have made an impact on the above environmental issues.

Implemented and planned measures to reduce the pollution of freshwater at national level

Since 2000, a number of fundamental laws have been adopted to ensure sustainable development of the water ecosystem and relevant Cabinet of Ministers regulations incorporating EU water legislation. The water management system has been reorganised and environmental protection measures are planned for river catchment basins[1]. River basin management plans have also been developed and measures adopted[2].

Measures have also been introduced to reduce point source discharge pollution. In order to curb discharge of pollutants from waste water, the whole of Latvia has been designated as highly-sensitive territory for which special urban waste water treatment requirements apply. In addition, authorities have been set up to regulate pollutant discharge and use of water resources. Between 1995 and 2008, environmental protection projects totalling LVL 488.15 million were implemented. The largest proportion (LVL 385.55 million or around 79 %)  was invested in water services development to improve waste water treatment and collection and to provide good quality drinking water. Most of the financing (LVL 93.56 million) originated from EU funds (Phare, ISPA, the Cohesion Fund and the European Regional Development Fund) and from bilateral cooperation programmes. In recent years, investments to develop environmental protection for water services have increased considerably in Latvia.

Figure 11: The dynamics of investments in water services development (LVL million per annum), 1995–2008

Source: Ministry of the Environment of the Republic of Latvia

Landfill sites which pose a potential risk as a source of point pollution have been reconstructed and historically contaminated sites are gradually being cleansed. From June 2010, a limitation will be imposed on phosphorus content in detergents: the maximum

permissible phosphorus content in household detergents must not exceed 0.5 % of the total mass.

To protect water and soil from diffuse source pollution, a part (12.6 %) of Latvian territory under intensive agricultural production has been defined as a nitrate-vulnerable zone. Various restrictions have been imposed on agricultural production in this area: buffer zones, limitations on the application of fertilisers, requirements governing manure storage, soil treatment methods, etc. In order to reduce diffuse pollution resulting from other human activities or originating in natural processes, protective belts have been established for watercourses and water bodies and in the vicinity of drinking water abstraction sites.

Considerable investments have also been made in waste management. Between 1995 and 2008, some LVL 79.59 million (about 16 % of all investment in the environmental sector) was invested in the development of waste management.