Objection to planning application (Ref: 17_38/2849/11/F Installation of a single screw turbine and associated switch gear to generate electricity, improvements to weir)

The Avon Fishing Association (AFA) objects to planning application (Ref: 17_38/2849/11/F Installation of a single screw turbine and associated switch gear to generate electricity, improvements to weir) on the grounds that it will have an overbearing impact on adjoining property.

The fishing rights on the river between the inlet and outlet points of the leat are the property of the AFA (Land Registry Title number DN546418).

The Fisheries Assessment report prepared by Fishtek and submitted with this application shows that at typical average summer flows approximately half the amount of water in the river would be diverted down the leat to service the turbine. This is a substantial interference with the amenity value of the fishery during the summer when the fishing is enjoyed by our members and visitors to the South Hams.

The Environment Agency (EA) granted the applicant a licence (SW/046/0005/001) in April 2011 to abstract water from the river. This licence was issued under EA guidelines that are now discredited. The Angling Trust noted that "The Good Practice Guidelines for hydropower developers have been found by the Environment Agency’s own advisers to be "unfit for purpose" and were initially drafted only with the input of hydropower developers rather than any other interests.” The national outcry over the way in which hydrogenation licences were handled by the EA was so great that they are now being reviewed in light of advice from the Angling Trust and other informed national bodies.

To make matters worse this application (Ref: 17_38/2849/11/F) even falls short of the now discredited guidelines.

Impact on amenity value

The EA defined a sustainable hydropower scheme as one that “maintains sufficient flow in any depleted reach to maintain the ecology and the fishery, including its amenity value.” (italics added). The EA was also obliged to consider the rights of fishery owners that may be affected.

The Fisheries Assessment report prepared by Fishtek (now available on the SHDC website as part of this application) was previously submitted by the applicant to support her application for an EA licence to abstract water. The AFA sent a letter of complaint to the EA because the views of fishery owners and the impact on amenity value were not adequately considered by the EA during the consultation period before that licence (SW/046/0005/001) was approved.

The AFA made a number of comments on the Fishtek report that will be revisited here because the same report forms part of the current application.

The report does not directly address the impact of the proposal on the amenity value of the fishery. It notes (section 6.3,page 18) that it is difficult to quantitatively assess the impact of  the proposal on the habitat. But it suggests that the available habitat could be reduced by 3-7%. Of course any reduction in habitat will reduce the amenity value of the fishery. But – as a fishing association - we draw a distinction between habitat impact and impact on amenity value. We do not agree with using the relatively small reduction in habitat to infer a similarly small reduction in amenity value. If 50% of the water is diverted down the leat during typical average summer flows then the amenity value (from a fisherman’s point of view) of the depleted stretch would be depleted by a similar amount – 50%. Therefore this application has an overbearing impact on an adjoining property.

It would be reasonable to bring the impact on the amenity value of the fishery into line with the ecological impact on the fishery (i.e. 3 to 7%). This would be straightforward to implement and monitor.


We endorse the comment in the Noise Assessment report that “The dominant source of noise in the valley is of water flow in the River Avon”. The turbine will be positioned on the river bank. The Noise Impact Assessment focuses on the noise impact on residential properties.  But our members and visitors fish during the day (and at night for sea trout) in the immediate vicinity of the proposed turbine. The report makes no attempt to consider this impact.  Our members are entitled to quiet enjoyment of their property. The current noise levels measured at the site ranged from 35 to 48dB – levels that might be experienced in a quiet library or average home. Section 4.1 presents data from the manufacturer showing that the turbine generates a maximum of 68-75dB – equivalent to standing next  to (1 m)  a vacuum cleaner or the kerbside (5m) of a busy road. The report refers to World Health Organisation-Guidelines for Community Noise. The level of noise produced by the turbine has the capacity to induce annoyance because of the difference between the noise of the river and that of the turbine.

We disagree with the Noise Impact’s conclusion the “During low water flow in the River Avon the proposed turbine will not be operating”. The Fisheries Assessment report shows that at typical average summer flows approximately half the amount of water in the river would be diverted down the leat to service the turbine. The turbine will not operate in drought conditions when fishing conditions are unfavourable anyway.

We object to application (Ref: 17_38/2849/11/F) because noise from the turbine will have an overbearing impact on the relative peace and tranquility offered by our property.

Impacts on fish

Section 5 of the Fisheries Assessment report describes the results from EA electrofishing surveys. All of these survey sites are upstream of the proposed site. The most recent survey – carried out in 2010 -is about 5km away. The nearest site (2 km) was last surveyed in 2007. According to EA guidelines “Where fish survey data to classify for WFD (Water Framework Directive)  above and below the site are not available, these will need to be provided by the developer to enable assessment against GES (Good Ecological Status ) to be made by the Environment Agency.” (our italics).  We cannot find this additional fish survey data in the developer’s application.

The Fisheries Assessment report commissioned by the applicant recommends that a quantitative electrofishing survey is conducted within the PDR (potentially depleted reach) to determine the existing state of fish populations. We must stress that this survey would be measuring fish populations in an already depleted stretch. The 470 yard stretch has suffered for many years from the loss of an unknown and unregulated amount of water.

In addition the situation might deteriorate even more under new licence conditions. Therefore there should be an agreed and enforceable series of pre- and post-implementation fish surveys, and an agreed set of enforceable mitigation measures. Section 6.12 of the licence to abstract water does not meet these concerns.

The Fisheries Assessment report estimates that about 65% of the depleted stretch provides spawning and good quality juvenile salmon and trout habitat. The remaining 35% is deeper water and is known to hold adult salmon and sea trout. It is reasonable to expect that any further reduction in flow will have a greater impact on the shallow areas – the 65% of the stretch that supports juvenile fish.

The report quite rightly points out that any abstraction should not lower water levels to such an extent that it interferes with fish migration. At the moment the report notes that three of the riffles in the depleted stretch are deep enough to allow upstream migration. But it expresses concern about Riffle#2. It recommends channel narrowing at this point. It is important to consider possible future deterioration in the remaining three riffles, and the possibility of new areas of shallow water developing along this stretch in the future. Therefore there should be an agreed and enforceable series of pre- and post-implementation depth surveys, and an agreed set of enforceable mitigation measures. The application contains no measures to address the concerns about riffles raised in the Fisheries Assessment report.

Salmonid spawning and growth

The Fisheries Assessment report points out that the depleted stretch may be a salmonid spawning area, and recommends a redd count this winter. A one-off survey is inadequate because salmonid spawning varies from year to year. It is important to consider possible future deterioration in spawning potential. Therefore there should be an agreed and enforceable series of pre- and post-implementation redd surveys, and an agreed set of enforceable mitigation measures.

Atlantic Salmon are protected by a range of relevant legislation and the North Atlantic Salmon Conservation Organisation Treaty to which the UK is a signatory through its membership of the European Union. Salmon, along with other fish species present including sea trout/brown trout, require adequate flows to migrate, reproduce and grow. Population levels are dependent on adequate wetted area as each juvenile occupies a feeding territory – reduced wetted area results in reduced population. Variability of flow is a factor in determining the geomorphology and sediment regime of a river. The application will reduce this variability over a 300m length.

Licence enforcement and conditions

Conditions 6.12 and 6.13 of licence (SW/046/0005/001) are very important because they deal with monitoring the impact of the application on fish stocks. We have serious reservations about the effectiveness of these conditions because the EA acknowledge they have an inaccurate and incomplete picture of current fish stocks in the river.


Anglers are obliged to send annual catch returns to the EA. According to the EA: “Angler catch returns are fundamental to UK and international effort to protect and improve salmon and sea trout stocks. The information you provide helps us measure how all the major rivers in England and Wales are performing against their Conservation Limit”.


The AFA has established that the EA is not able to provide accurate figures for the number of salmon and sea trout caught by anglers on the river. This is because the EA’s internal data recording systems do not distinguish between the Devonshire Avon and other rivers named Avon. The EA acknowledge that the published catch returns for the Devonshire Avon catch are inaccurate. In addition, the EA acknowledge that it needs to undertake further investigations to increase its confidence in its classification of the state of fish stocks in the river (EA Waterbody Information Pack Avon Waterbody – January 2011).


Given the lack of accurate baselines it will be impossible to judge if this planning application has had a negative, neutral or positive impact on fish stocks.


Therefore we believe that - under the requirements of European Environmental Legislation - the precautionary principle should apply in this situation, and planning application (Ref: 17_38/2849/11/F ) should not be granted until the EA have a complete and accurate picture of fish stocks in the Devonshire Avon that can be used to monitor the impact of the application to ensure that it  will cause no harm to the environment.


Conditions 6.12 and 6.13 in abstraction licence (SW/046/0005/001) deal with a fish monitoring programme. They do not contain any reference to the involvement of the AFA, or other riparian owners potentially affected by the abstraction.

Furthermore there is an overarching national problem with the EA’s ability to enforce hydropower licence conditions. The Angling Trust has stated that “Some hydropower schemes breach their licence and permit conditions and yet there is no enforcement from the Environment Agency as the breaches of each condition are not regarded as significant enough on the Compliance Classification Scheme to warrant action by the Agency. This means that a developer or operator could breach every single condition consistently”


Large woody debris

The banks of the river are lined with mature trees. From time-to-time trees collapse and fall into the water. When the river is in spate these fallen trees are swept downstream. During a typical spate (not flood conditions) about 25% of the flow would be diverted down the leat to service the turbine. Consequently there would be reduced flow below the weir in the depleted stretch.  This will increase the risk of large trees becoming stranded along the depleted stretch. We have experience of the costs involved in removing and repositioning fallen trees in the river. It is unreasonable to expect the AFA to mitigate this overbearing impact of planning application (Ref: 17_38/2849/11/F) on its property.


It is now recognized that weirs can have detrimental effects on river life:

·         Some weirs can prevent fish from completing their life cycle. Nearly all fish, from minnows to salmon, need to move up and down stream to breed and feed.

·         By depleting the flow of water in the stretch of river out of which water is taken to power the turbine. This has impacts on invertebrate life and the ability of fish to migrate through this depleted reach.

·         By preventing the natural movement of sediment and gravel down the river which can have an adverse effect on spawning gravel used by salmonids below the weir

·         By acting as a ‘pinch point’ that increases the risk of predation


However Nature is reducing these adverse impacts of Curtisknowle weir. The weir is currently in an advanced state of decay. The proposal in the planning application to repair the weir runs counter to Angling Trust advice to the EA that hydropower should only be approved “if it is installed on an existing weir and that weir cannot be removed or eased for technical reasons or because it has some other legitimate and long standing function (such as navigation on heavily used rivers). “


Ownership and responsibility for upkeep of Curtisknowle weir has been a persistent problem as far back as the 1970s. The application proposes to modify the existing weir and construct a notch to enable fish migration.  The main fish passage over the weir is now on the right hand side of the medium filum . It is proposed that a notch be cut in the weir at this point to allow fish migration even at low flows. It is important to establish who owns that part of the weir. Before work begins ownership of the weir on the right hand side of the medium filum should be clarified and registered with Land Registry because there is a need for clear and enforceable responsibility for the upkeep of this notch in the future .

The weir and leat were constructed several hundred years ago, long before the Avon Dam was constructed. The dam is acknowledged to have reduced the amount of water available to the river. Repairing the weir to divert flow down the leat will exacerbate the existing undesirable situation in the potentially depleted stretch.

Using a weir to divert flow down a leat reduces the amount of time that flows are suitable for migration of fish. The effects of these obstructions are cumulative. The Devonshire Avon already suffers from low flows caused by the Avon Dam. Where there are several installations on a single river this can mean that fish are unable to reach their spawning or feeding grounds.


The Water Framework Directive requires Governments to protect and improve the water environment. The EA has expressed concern about the current status of the river: “The waterbody has a current status of Moderate. The Avon waterbody must achieve overall Good Ecological Status (GES) by 2027 but fish must improve to Good Ecological Status by 2015.   The failing elements in this waterbody are fish and pH” (EA Waterbody Information Pack Avon Waterbody – January 2011). The EA has launched a consultative exercise with various stakeholders including the AFA to identify measures to achieve Good Ecological Status under the Water Framework Directive by 2015  . The AFA highlighted the EA’s handling of the applicant’s water abstraction licence as an example of the EA’s failure to consider the cumulative effect of adverse impacts on the future ecological status of the river.


Conclusions and suggestions

In its present form the application (Ref: 17_38/2849/11/F) would have an overbearing impact on our property.


In our opinion this planning application

·         will not help the Devonshire Avon improve its ecological status under the Water Framework Directive by 2015

The main aim of the Avon Fishing Association is to improve the fishing on the river. We do not have resources to mitigate the effects of foreseeable and avoidable adverse impacts on our fishing. 

The AFA is not in principle opposed to hydrogenation. We suggest that the application be modified to bring the impact on the amenity value into line with the ecological impact on the fishery (i.e. 3 to 7%). This modification would go some way to meeting our concerns about the impact of the application on salmonid spawning and growth, fish stocks, noise pollution, and deposition of large woody debris in the depleted stretch.

Before this planning application is approved the developer should provide evidence that the application will not cause appreciable damage to the Devonshire Avon. The application should be reconsidered in the light of revised Hydropower Good Practice Guidelines that the EA plans to publish at the end of this year (2011).


Paul Kenyon

Chairman and Trustee Avon Fishing Association