Freshwater

Photo: Kim Abel, naturarkivet.no

Norway  is home to one third of the world’s wild Atlantic salmon stock, but the species is threatened by the parasite gyrodactylus salaris, acidification and watercourse regulation. There is also growing pressure from aquaculture in the form of increasing numbers of sea lice and escaped farmed fish interfering with wild salmon.

Around 25 per cent of Norway’s water courses are at risk of not obtaining good ecological and chemical status within 2021. Long range transboundary pollution causes acidification and brings hazardous substances to lakes and rivers, most severely in the south and in the north eastern part of the country. Partly as a result of this, concentrations of mercury are so high that advice against consumption by pregnant and breastfeeding women has been issued. 

Despite the introduction of numerous measures in recent years, problems with acidification and eutrophication still remain. In the future, climate change is likely to escalate the problems, particularly with regards to increased run offs and the spreading of alien species. 

Environmental conditions in Norwegian rivers and lakes are good compared with those in most other countries in Europe. A preliminary survey of the status of all Norwegian water bodies shows that around 50 per cent probably will meet the EU objectives for the freshwater environment, while around a quarter are at risk. The rest lacks data or has uncertain status. There are wide regional variations, and not surprisingly, environmental conditions are poorest where the population density is highest.

Norway has nine of the world’s 20 highest waterfalls but water flow in seven of these has been affected by hydropower regulations. More than 70% of Norway’s largest rivers are regulated for hydropower production.

Only around 7 per cent of Norway’s fresh water is characterised as ground water, and accounts for a mere 15 per cent of the water consumption. This is very low compared to many other countries in Europe and is due to the country’s abundant supply of surface water.

However, in later years there has been an increase in the use of ground water in districts with a scattered population. Every year, around 6000 new wells are drilled, but only 40 per cent of these wells are used for water consumption. The rest are used for energy production.

Emissions of hazardous substances have been substantially reduced since the 1980s. However, even in the most remote lakes in Norway, we find these substances due to transboundary pollution. The deposition of airborne mercury originating from other countries is estimated to be twice that of Norwegian emissions in total. The levels of mercury in fish from lakes in the Norwegian Arctic are in the same order of magnitude as in fish from lakes in Southern Norway, and the levels of PCB cause reduced fertility in birds and mammals. PCB and newer substances such as brominated flame retardants and perfluorinated compounds are so high that weakened immune response, hormone disruptions and elevated death risk for the offspring are expected.

Eutrophication is still a problem in many rivers and lakes despite the introduction of numerous measures in recent years. Environmental monitoring shows that the situation has remained unchanged in the last ten years, most likely because of climate change. The following map shows the effect of phosphorous on water quality in rivers and lakes.

Acidification used to be an escalating issue in Norway up until the late 1980s. More than 15.000 fish stocks became extinct or affected. 25 salmon stocks have been lost due to acidification, and at least 20 have been affected. Thanks to international cooperation, the situation has improved. A reduction in emissions, together with the liming of rivers and lakes has reduced the total area affected by acidification by 38 per cent from 1990 to 2006. However, long-range transboundary pollution is still a problem, especially in Southwest Norway, and the top impact on Norwegian water courses.

The wild salmon is threatened

The Norwegian wild salmon is threatened by several pressures, some of the most severe being the increase in numbers of sea lice in coastal areas with extensive aquaculture industry, escaped farmed salmon invading the rivers and the invasive parasite Gyrodactylus salaris. Extensive aquaculture industry has led to an increase in numbers of sea lice in the fjords, representing a threat especially to migrating smolts heading for the ocean. Escaped farmed fish enter the rivers, disturbing spawningwild stock both by damaging spawning areas and by genetic mixing as they participate in the spawning. The salmon stocks are specially adapted to each river, and genetic mixing interferes with this unique adaptation and result in lesser production of salmon in the rivers.

Several rivers are undergoing treatment to remove Gyrodactylus salaris, and treatment will continue for years to come.  Stocks also meet pressure from watercourse regulation, and due to acidification, liming is still needed to prevent stocks from extinction.  Norway has an international responsibility to protect its stocks of wild salmon, and faces many challenges in this respect as pressure is increasing.

 According to the 2006 Norwegian Red List, there are 328 endangered freshwater species, and a  major challenge in Norway is loss of species and habitats due to morphological alteration associated with watercourse regulation, dumping, dredging, embankments in littoral zones and infilling of ponds. In addition, water quality is affected by nutrient runoff, pollutants and liming etc, putting additional strain on species. Alien species represent a threat through the invading of habitats and spreading of parasites and diseases. Climate change is considered to be a threat to 12 per cent of red-listed freshwater species.

In the last 50 years, there have been major changes in settlement patterns and patterns of leisure activity in Norway. More and more people have moved from rural districts to urban areas, and major improvements have been needed in the way waste water from towns and urban areas is managed and treated. The changes in settlement patterns have put more pressure on watercourses near the largest urban areas. However, Norway utilises only one per mil of its water resources, and water extraction puts little pressure on water resources.

Environmental pressures on Norwegian rivers and lakes can be divided into three main groups:

• pollution: includes point sources, fugitive emissions, and long-range transboundary pollution, which may result in acidification, eutrophication and the spread of hazardous substances
• physical alteration: mainly as a result of hydropower developments, but other examples are transport infrastructure, which may act as a barrier to fish migration, and canalisation of rivers for agricultural purposes
• biological pressures: include the introduction of alien species such as minnows and pondweed, the escape of farmed fish, and parasites such as salmon lice.

The most important pressures on Norwegian water bodies are long-range pollution and morphological alterations of water bodies, followed by pollution from agriculture and waste water.

Major hydropower developments are not an issue at present, but existing plans and regulations pose great stress on habitats. Hydrological alterations in form of fluctuations, dry rivers and sedimentation impair quality on habitats and can have lethal effects on species. 

Climate change is expected to cause an increase in nutrient runoff and serves to reduce the effect of measures to alleviate this problem. It is expected, therefore, that the need for additional measures to achieve such runoff reductions is increasing. Climate change will make our watersheds more hospitable to alien species, and is expected to be a threat to some freshwater species.

The infrastructure for waste water treatment is not dimensioned for the increase in precipitation which most likely will be caused by climate change, resulting in increased discharges of pollutants to water bodies.

The Norwegian government has set a national target to draw up integrated water management plans for every lake and river by the year 2015.

The Norwegian priority list includes about 30 substances and groups of substances that pose a serious threat to health and environment. Norway’s national targets demand that use and emissions of these should be continuously reduced, with the aim of stopping emissions altogether by 2020.

The EU Water Framework Directive was incorporated into Norwegian law at the end of 2006. However, the Regulation was not formally incorporated into the EEA-agreement until 2007 and entered into force in May 2009. The Water Management Regulations divides Norway into river basin districts managed by 9 river basin district authorities. Initially, water management plans and programmes of measures have been made for a pilot group of 30 selected sub-districts representing about 20 % of Norway’s watercourses. Characterisation has been performed for all water bodies, but at present only water bodies in the selected sub-districts has been classified according to criteria for status set in the directive.

The EU Ground Water Directive is planned to be incorporated into the Norwegian Water Management Regulations in 2010. The directive is not yet part of the EEA Agreement. Norway has implemented the Urban Waste Water Treatment Directive by establishing national regulations.

A new Nature Diversity Act of 19.6.2009 will provide means to protect biodiversity. The Act contains important environmental principles such as the precautionary principle, the ecosystem approach and the polluter pays principle, extending beyond the scope of pollution. Designation of selected habitat types and pointing out priority species and their natural habitats will influence activity in these areas.

The Norwegian government has initiated the development of a Nature index for Norway. The index will be an essential tool to monitor the overall trend in nature over time (for more information, see biodiversity).