A weir and fish ladder in a river. Photo: Line Fjellvær

Growing pressure on lakes and rivers

There are growing pressures on Norway’s river systems – from physical alterations and hydropower developments to acid rain and releases of hazardous pollutants and nutrients, the spread of alien species and climate change. 

A preliminary assessment of 16 000 rivers, streams and lakes in Norway shows that more than half of them will probably meet the criteria for good ecological and chemical status set out in the Water Management Regulations by the 2021 deadline. But about one in four are unlikely to meet these standards unless action is taken.

Hydropower has the widest impact

About one third of Norway’s total freshwater area is affected by hydropower developments, making this the factor with the widest impact. Seventy per cent of the largest river systems are regulated. Nine of the world’s 20 highest waterfalls are in Norway, and seven of them are regulated.

Acid rain

Acid rain causes problems for fish, vegetation and benthic animals. More than 15 000 fish stocks have been wiped out or depleted by acidification. Norway has lost 25 salmon stocks, and at least 20 others have been depleted. Large areas, especially in the southern half of the country, are still being affected by acid rain, and extensive liming is needed to counteract the damage.

Only half of Norway’s larger river deltas are intact

River deltas are important habitats for many birds, other animals and plants, but they are also suitable for cultivation, road building and industrial developments. Half of the 290 largest river deltas in Norway are moderately or severely affected by such developments.

Alien species a threat to the environment

Alien species that become established in or along river systems may have a serious negative impact on ecosystems. They can spread diseases and parasites that may cause the extinction of native species, and may also compete for food with or feed on native species.

Project to register pressures on water bodies

Everyone who uses water resources in Norway or puts pressure on the aquatic environment is expected to join forces to safeguard the fjords, river systems and groundwater, improve their environmental status and avoid new environmental problems. A “health check” of all Norway’s water bodies is under way, and any factors that may have negative impacts are being registered.

Information and data are being collected locally for each water body and are being compiled for each sub-district, with a summary for each river basin district. The driving forces and activities underlying the different pressures are also being registered. This will provide information that is needed to plan what action the companies, sectors or authorities responsible for different pressures need to take. The project will provide an overview of which problems must be tackled to avoid damage to the aquatic freshwater environment and which should be given priority in Norway’s efforts to achieve the target of good ecological and chemical status in the freshwater environment. 

The information collected is being made available in a map-based web application called Vann-Nett[A2] . This enables anyone who is interested to find out what has been recorded about a particular water body or for an administrative area or river basin district.

The results so far show that, not surprisingly, there is a tendency for the state of the freshwater environment to be poorest in the most densely populated parts of Norway and better further north. It is important to ensure that in the long-term, the cumulative effects of human activities do not exceed sustainable levels and disrupt natural ecosystem dynamics.

Risk of failing to meet environmental objectives

As part of the project, likely trends for the pressures that have been registered are being assessed – are developments likely to put more or less pressure on a water body in future? And how likely it is that a particular water body will achieve or maintain good environmental status?

This process is required by the Water Management Regulations and the Water Framework Directive. If it is considered likely that a water body will not achieve good environmental status in the next six years, it is classified as “at risk of failing to meet environmental objectives”. It is then up to the relevant municipalities and the authorities responsible for water management to take steps to remedy the situation.

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