Running Water : Hydropower Development on Small Waterways
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Swedish Society for Nature Conservation Running Water Hydropower development on small waterways – small benefits but large-scale damage Hydropower has devastated the majority of Sweden’s large In southern Sweden, there are few, rivers. The continued exploitation is now aimed at small if any, waterways that have not been waterways. In order to facilitate the construction of mini regulated for hydropower or not been power stations, the Swedish parliament has allocated sub- affected by other types of physical sidies to small-scale hydropower1. This decision will lead actions. A small number of waterways to the impoverishment of the original ecosystems in run- are protected against further exploi- ning water. The Swedish Society for Nature Conservation tation. It is really only in the far north, believes that the continued destruction of Swedish water- in northernmost Lapland, where the ways cannot be accepted. There is even within the EU the waterways are essentially unaffected by development. But even here, in intention to encourage small-scale hydropower. areas affected by forestry activities, 1When a power station is built on a smaller waterway, it is usually referred to as a mini power station or small-scale hydropower. the construction of roads and ditches Ljung River mini power station under construction on the Ljung River, Bräcke municipality in central Sweden. Capacity 1,200 kW, dimensioned water discharge 9 m3/s. The concrete dam that will force the water to flow through the turbine of the power station can be seen in the background. The river is hidden behind the cover in the centre of the picture. At the very right the river is visible but covered with ice. Photo: Hans Isgren has lead to the radical disturbance of hours (TWh) within five years. This is energy resources, there is also the many smaller waterways. the equivalent of less than 0.4 per intention within the EU to encourage On a European level there re- cent of today’s average hydropower small-scale hydropower. One pro- mains a very small number of large production during a year, and less posal suggests that small-scale hydro- river systems in their original con- than 0.2 per cent of Sweden’s total power should increase by 50 per dition. One of these is shared by electricity production. However, even cent during the period 1995–2010. Sweden and Finland. It is not only more of the irreplaceable living envi- a matter of national concern to pre- ronments of the plant and animals Red-listed and other serve the last remaining free running that inhabit running waters will be sensitive species rivers, but also of international con- destroyed for ever. The single factor that has shown itself cern. As most of the large waterways In contrast to what many people to threaten most red-listed species in have been exploited for hydropower may imagine, a mini power station is Swedish lakes and waterways is the purposes, it is even more important to neither small nor ”cosy”. It is the word regulation of rivers for hydropower. preserve the many small waterways mini that is misleading. Seen in rela- According to the National Swedish that make a highly important contri- tion to the size of the waterway, it is Environment Protection Board’s book bution to the variation and biological not at all smaller than a ”large” power Biological Diversity in Sweden, diversity in the landscape. station. 177 red-listed freshwater species In the summer of 1997, the Swe- The amount of electricity that is are under threat from the regulation dish parliament decided to provide generated by a mini power station is of hydropower. Thereafter follow state subsidies for ”environment- very small. In Sweden there are about over-fertilization (107 species) and friendly, small-scale hydropower sta- 1,550 hydropower stations. Together increased acidity (80 species). tions”, as they are called in the Gov- these give, in a year with normal pre- But it is not by any means only ernment’s energy proposition. Build- cipitation, 65 TWh. 63.5 TWh come species living in water that are threat- ers of power stations can receive from the 350 largest hydropower sta- ened by the regulation of hydro- subsidies equivalent to 15 per cent tions. The remaining 1,200 hydro- power. Even species that are con- of the total required investment. The power stations are mini power sta- nected to running water, but that decision is deeply unfortunate. The tions, and electricity production in exist above the water line, can be extra energy provided by the devel- these only reaches 1.5 TWh per year. also seriously affected. What these opment of small-scale hydropower is Most of the mini power stations are in species have in common is that they marginal. The Government itself cal- the south of Sweden. are dependent on the natural water culates the increase as 0.25 terawatt As part of the drive for renewable level fluctuations that occur in a pre- Reservoirs and dry rapids Hydropower development requires up in the water system (in Sweden usu- are more or less highly fragmented by extensive interference with the natural ally in mountain areas). Annual regula- dams. In the SMHI (Swedish Meteoro- environment. The original, running tion is carried out because electricity logical Office) dam register there are water plant and animal life is replaced demand is greatest during the winter 5,290 dams registered. The register is by lake species. Dams are built on when there is little water in the rivers. based on an inventory of dams that the waterway to force the water to go The extremely high water volumes during was carried out by county councils at through the power station’s turbines spring floods are reduced and stored the end of the 1980s. instead of along its natural course. for use in the winter months. The varia- Examples of other developments Rapids and waterfalls become dry. tions between different times of the year that have had great effect on Swedish Sometimes the power companies are are therefore less noticeable. But the waterways are clearing for the floating required to release a certain minimum water flow in the rivers is still like a of logs and various forms of digging water flow along the original water ”mirror image”, there being high water and straightening. In farming areas, course. The dams are also used to during the winter and low water in the many small waterways have been led store water from night to day (short- summer. The height of water levels in through culverts. It has been necessary term regulation) and from summer to the annual reservoirs can vary by 35 to use culverts beneath all roads in the winter (annual regulation). Short-term metres. Along the shores, enormous countryside. Most of the innumerable regulation, which is carried out close to sterile areas are formed which are alter- road culverts have been laid in such the power stations, leads to extensive natively flooded or left dry and where a way that they hinder the passage of erosion of the river shores. The annual almost nothing can grow. animals up and down the waterways. A regulation reservoirs are situated high Most of the waterways in Sweden serious but overlooked problem. 2 Running Water European view: only four large, untouched water systems, of which three are in Russia Most of the large waterways in Tärendö River which transfers over half fragmentation by dams, and partly on Canada, USA, Europe and the former of the waters from the Torne River to how much the natural water flow has Soviet Union are to a greater or lesser the Kalix River quite high up in the river been affected by reservoirs, and use extent affected by regulation and dam system. for irrigation. constructions. This is shown by a The lower limit for large river sys- A survey was carried out for survey that was published in 1994 in tems has been put at an average medium-sized river systems (average the Science journal. In Europe there water flow rate of 350 m3/s. This aver- water flow rate greater than 40 m3/s remain only four large river systems age water flow should be achieved but less than 350 m3/s) in Denmark, that run freely from source to outlet. somewhere along the river (normally Finland, Norway and Sweden. These Three of these are in northern Russia the water flow is greatest at the river river systems were shown to be and the fourth is in Sweden and mouth, but in desert areas the flow greatly or moderately affected to an Finland. The Swedish-Finnish river becomes less towards the river mouth). even greater degree than the large system is the Torne and Kalix Rivers. An estimate has been made of how river systems in Canada, USA, Europe The rivers are regarded as one river much each river has been affected. and the former Soviet Union. system, as they are connected by the This was based partly on the level of Remaining unaffected large Gunnilbo River is by no means un- usual. The increased regulation of this river systems in Europe waterway is typical for what has hap- U pened after the upgrading of many r a mini power stations that have taken l Pechora Torne and place in Sweden during the latest 25 M Kalix älv Mezen o u years. n Onega t The lakes and waterways in the a i water system that includes the Gun- n s nilbo River are by no means any virgin environments. Dams built for mining and iron processing have existed at least since the 1600s.