Flood and Water Management Act 2010: changes to reservoir regulation take effect

The Flood and Water Management Act 2010 has altered the statutory framework governing the way in which reservoirs are currently controlled and managed.

Background to the law

Responsibility for the management and supervision of reservoirs in England and Wales is regulated by the Reservoirs Act 1975.

The administration and enforcement responsibilities under the 1975 Act are enforced by the Environment Agency.

What is the aim of the new changes?

Before the changes took effect, the owner of a reservoir was bound to comply with the 1975 Act irrespective of whether or not the reservoir posed a threat to surrounding land.

Under the 2010 Act, the Environment Agency is now directed to take a more risk-focused approach to reservoir safety.

What changes have been made?

Crucially, the 2010 Act has altered the threshold for what constitutes a "large" raised reservoir from one which is designed to hold 25,000 cubic metres of water to one which is designed to hold 10,000 cubic metres or more.

What constitutes a "raised reservoir"?

Under the 2010 Act a "raised reservoir" is a reservoir which comprises a "raised structure or other area which is capable of storing water and which has been created by artificial means".

A structure or area will be considered "raised" if it is capable of holding water above the natural level of any part of the surrounding land.

What are the implications if my development proposals require the construction or alteration of a large raised reservoir?

You will need to ensure that a qualified sewer engineer is employed to design and supervise the construction or alteration in accordance with the statutory regime.

Does the ongoing inspection regime apply to all large raised reservoirs?

No. The Reservoirs Act 1975 introduced a periodic inspection regime in relation to all large raised reservoirs. However the 2010 Act has amended those provisions so that they now only relate to those large raised reservoirs which are designated as "high risk reservoirs" by the Environment Agency.

Will I need to register a large raised reservoir with the Environment Agency, even if the reservoir is not designated "high risk"?

Yes. You will still need to register the reservoir with the Environment Agency, but will not need to comply with the periodic inspection requirements under the 1975 Act.

How will the Environment Agency determine whether a reservoir should be designated as high risk?

The Environment Agency is currently consulting on the most appropriate method of assessment, although the 2010 Act designates a large raised reservoir as being "high risk" if the Environment Agency considers that:

"...human life could be endangered in the event of an uncontrolled release of water from the reservoir and the reservoir does not satisfy the conditions specified by the Secretary of State's regulations".

While those regulations have yet to be announced, the 2010 Act anticipates that they will have regard to the following matters:

• The purpose for which the reservoir is used
• The materials used to construct the reservoir
• The way in which the reservoir is constructed
• The ongoing maintenance arrangements for the reservoir.

What are the implications if my development requires ongoing compliance with the 1975 Act?

Apart from the requirement to construct or carry out any works to a large raised reservoir in accordance with the statutory regime, you will need to factor in the cost implications of the ongoing maintenance in both your development appraisal and any onward estate management arrangements. In particular, all administrative and maintenance costs will need to be included within any estate charges to be passed on to the end users of the scheme.

While the detailed arrangements for the implementation of the new statutory provisions have yet to be announced, developers will need to have regard to the legislative changes which are now in force in relation to all current and future schemes.