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Reservoirs

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Reservoir safety in Scotland

SEPA is the national regulator for reservoir safety, under the Reservoirs (Scotland) Act 2011.

This means we:

  • maintain a publicly available Controlled Reservoirs Register (CRR) which includes a reservoir inundation map for each registered reservoir, showing the area of land likely to be flooded in the event of an uncontrolled release of water.

  • are your contact for reporting a reservoir incident.

  • assign a risk designation (high, medium or low) to each registered reservoir, based on the consequences of an uncontrolled release of water.

The majority of dams require authorisation from SEPA under the Environmental Authorisations (Scotland) Regulations (EASR), which replaced the Water Environment (Controlled Activities) (Scotland) Regulations 2011 (CAR) in November 2025.

Any authorisation previously issued under CAR is deemed to be an authorisation under EASR. Authorisation references will typically begin CAR/.../... or EASR/.../..., with EASR references applying to authorisations issued after November 2025. If you do not have an authorisation for your dam, you should contact us to discuss your situation.

Constructing a controlled reservoir

Before construction

If you are planning to construct a controlled reservoir, you must appoint an approved construction engineer from the Scottish Government All Reservoirs Panel, to supervise and certify the construction works.

Reservoir managers must submit an appointment of a construction engineer form to SEPA, at least 28 days before the work commences.

After construction

Following completion of the works and production of a preliminary certificate by the construction engineer, the reservoir manager has 28 days to register the reservoir with SEPA.

Register a reservoir

Who needs to register a reservoir

You must register a reservoir with us if it has the capacity to hold 25,000m3 or more of water above the natural level of the surrounding land.

If your reservoir is under construction, you need to register it with us within 28 days of the construction engineer issuing the first preliminary certificate.

If your reservoir has been built, but is not registered, you must do so immediately.

How to register a reservoir

To register a reservoir with SEPA, reservoir managers must:

For an overview of the pre-registration, registration and post registration process, read the registration overview.

Appointing reservoir engineers

Reservoir managers must appoint:

The Scottish Government are responsible for approving the Engineers appointed, and updating and maintaining the panel details.

We have produced information for panel engineers operating in Scotland under the Reservoirs (Scotland) Act 2011.

Reservoir risk designations

SEPA is required to assign a risk designation (high, medium or low) to each registered controlled reservoir.

Risk designations:

  • are based on the consequence of an uncontrolled release of water, and the impact that this could have on the surrounding area below the reservoir (this means a high risk designation does not necessarily mean that a reservoir has a higher risk of flooding)

  • direct the statutory level of engineering inspection and supervision that is required at a site

  • are calculated using national datasets held by SEPA, the Scottish Government or associated organisations.

How we assign risk designations

Provisional risk designations

After the reservoir manager registers a controlled reservoir, we will provide them with a provisional risk designation.

If the reservoir manager disagrees with the provisional designation, they have two months from the date they received it, to make an appeal:

Appealing to review a risk designation

We will notify reservoir managers of a risk designation two months after the provisional risk designation is issued to a reservoir manager.

If a reservoir manager disagrees with it, they have 12 months from the date the notice was given to apply for a review.

The Reservoirs (Scotland) Act 2011, under section 20, requires SEPA to review a reservoir’s risk designation within a period of 6 years after it was initially given and thereafter every 6 years.

  1. Read the reservoir risk designations: guidance on representations and reviews

  2. Complete the risk designation review application form.

There is a fee to apply for a review. Read the Reservoirs (Scotland) Charging Scheme 2024 for more detail.

For more information on the risk designation process, read reservoirs briefing note: risk designation.

How risk designations impact land use planning and development

We have considered the usefulness of the information contained in the reservoir inundation maps for land use and development planning, and have concluded that the maps are not appropriate to inform this process.

For more detail, read our two position statements:

Reservoir charging scheme

The Reservoirs (Scotland) Act 2011 gives Scottish Ministers the power to make provisions for SEPA to recover the direct regulatory and administrative costs of carrying out SEPA’s duties in relation to controlled reservoirs. 

For more information on the charging scheme, including payment methods, subsistence fees and general fee amounts, see our guidance on the The Reservoirs (Scotland) Charging Scheme 2024.

Reservoirs privacy notice

For information on how we collect and use personal information to carry out SEPA's regulatory duties under the Reservoirs (Scotland) Act 2011 and Reservoirs (Scotland) Regulations 2016, see our privacy notice.

Contact us

For further enquires relating to the implementation of the 2011 Act please, contact us by email.