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Before you apply

Hydropower Guidance Notes and supporting information


Hydropower schemes can be complex and need to be designed and managed carefully to avoid unacceptable impacts on communities and the river environment. For example, changes to a river can increase the risk of flooding and have significant impacts on wildlife, especially fish.

We have published Hydropower Guidance Notes (HGNs) and Supporting Guidance Notes (SGN) below, which provide advice and technical guidance for designers and developers of hydropower schemes.

The  notes will also provide guidance on what you should do to comply with environmental and other legislation. We strongly recommend that you read this guidance before you start to choose the location and design of your schemes and before you make any pre application enquiries or formal applications.

You will need to apply for one or more licences, approvals or consents depending on the type of scheme you are proposing. These are needed to ensure your scheme has a low impact on the environment. They may include controls or conditions on your scheme including, for example, how much water you can abstract or impound, or environmental design requirements such as the need to build a fish pass or easement.

Related document downloads

Supporting Guidance Note - SGN 1 Rights of access guidance for abstraction licences PDF [210.6 KB]
Supporting Guidance Note - SGN 2 Geomorphology photosurveys for hydropower developments PDF [1.7 MB]
Hydropower Guidance Note - HGN 3 Water Framework Directive PDF [122.1 KB]
Hydropower Guidance Note - HGN 4 Designated Sites PDF [215.4 KB]
Hydropower Guidance Note - HGN 5 Cumulative and in Combination Effects PDF [119.1 KB]
Hydropower Guidance Note - HGN 6 Nature Conservation, Heritage, Amenity and Landscape PDF [162.9 KB]
Hydropower Guidance Note - HGN 7 Competing schemes PDF [192.1 KB]
Hydropower Guidance Note - HGN 8 Fish passage PDF [192.1 KB]
Hydropower Guidance Note - HGN 9 Fish Screening PDF [342.2 KB]
Hydropower Guidance Note - HGN 10 Geomorphology PDF [342.9 KB]
Hydropower Guidance Note - HGN 11 Monitoring PDF [209.5 KB]
Hydropower Guidance Note - HGN 13 Approvals, Licences and Consents PDF [428.3 KB]
Hydropower Guidance Note - HGN 14 Weirs PDF [129.0 KB]
Hydropower Guidance Note - HGN 15 Weir pools PDF [158.7 KB]

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