Scottish and Southern Energy's application review

  02 April 2014
The Scottish Environment Protection Agency (SEPA) is well advanced in determining Scottish and Southern Energy’s (SSE) application to modify flows within areas of the Tay and Spey catchments in order to improve the quality of some rivers as required by the European Water Framework Directive.

Colin Anderson, SEPA’s Area Manager said:

“We have determined the appropriate flows for all of the water bodies in accordance with the guidance set down by UKTAG ( Revised flow figures were given to SSE in mid March and SSE has now confirmed how these changes would affect generation from the hydroscheme, and confirmation of what flows they consider are technically infeasible to provide.”

Once SEPA has assessed the information submitted by SSE a draft determination of the application will be produced. SEPA continues to ensure that key stakeholders are actively engaged in the process and we are working to conclude this matter as quickly as possible, while considering all the important elements.

When assessing this application SEPA is required to balance the important benefits which renewable energy generation provides to society and our economy, and the ecological benefit of reintroducing water to rivers that have been historically impacted by the construction of hydro schemes. It is important that improving these affected waters does not significantly compromise generating power, and also that altering flows in any river will not result in any deterioration in that river or any subsequent catchments downstream.

Colin Anderson also explained:

“Both the Tay and Spey catchments contain Special Areas of Conservation, which are designated for Atlantic Salmon and lamprey species, and also contain internationally important populations of Freshwater Pearl Mussels. There are also Sites of Special Scientific Interest (SSSI) downstream of several of the waterbodies.

“Changes to flows, whether from increases or decreases in volume, or introducing greater variability, can affect ecologically sensitive species. This application requires very careful consideration and, while any conditions may be reviewed at points in the future to ensure they are still appropriate, we want to ensure that we make the right decisions from the beginning.”

SEPA is also currently working with SSE and the Tay District Salmon Fisheries Board on a flow trial in the River Garry. This trial will compare low flow options to ensure that the most ecologically suitable flow is licensed as a result of this application. This is very important as discussions with SSE have suggested that there is a significant issue regarding the proposed volume of water to provide adequate flows within the River Garry and how this will affect generating capability.


Background information

  • Scottish and Southern Energy (SSE) has applied for variations to its authorisation under the Water Environment (Controlled Activities)(Scotland) Regulations 2011 (commonly known as CAR) for some of the controlled activities it operates as part of its Tummel Valley hydroelectricity scheme, CAR licence number CAR/L/1011485.
  • The variation application principally relates to the increase or decrease of flows released into certain water bodies. These are significant changes to the existing operational regime.
  • The Tummel scheme is one of Scottish and Southern Energy’s oldest and most extensive assets, with nine power stations and a total installed capacity of approximately 245 megawatts.
  • The Tummel catchment area extends over 1,800km2 and utilises water from both the River Tay and River Spey catchments.
  • All water bodies within the scope of SSE’s application have been designated as heavily modified due to changes to the physical shape and characteristics of the bed and banks of rivers, such as river straightening, culverting and building dams for the purpose of electricity generation.
  • The affected waters have been identified as heavily modified with an objective of good ecological potential. This means that although human activities are currently impacting on plant and animal communities, this can be minimised through changes to provide the best ecological conditions practicable, though never completely reversed.
  • These rivers cannot be returned to a completely natural condition as this would affect the generation of power, and therefore the benefits this scheme provides to society and the economy.
  • SSE's proposals are aimed at improving the ecological potential of several of the rivers it abstracts water from, to contribute to them achieving good ecological potential by 2015, an objective established in the Scotland River Basin District Management Plan. Other abstracted water bodies within these catchments are identified for improvements in future cycles up to 2027.