Barratt Homes sought a court declaration that it was entitled to have its development connected with the public sewers. The local water authority, Welsh Water, had objected to Barratt's planning application on the grounds that it would overload the public sewerage system. Planning permission for the development was granted, subject to a condition that no development should take place until a scheme of foul drainage and surface water drainage had been submitted to, and approved by, the local planning authority.

Barratt then served a notice on Welsh Water under section 106 of the Water Industry Act 1991. Section 106 provides that the owner or occupier of premises, or the owner of any private sewer, is entitled to have its drains and sewers connected to the public sewer, and to discharge foul and surface water from those premises into the public sewer.

A sewerage undertaker may refuse to permit the connection if the mode of construction or condition of the private sewer does not satisfy the undertaker's reasonable standards, or is such that the making of the communication would be prejudicial to the undertaker's sewerage system.

Barratt's notice specified a particular connection point where the connection to the public sewer would be made. However, the public sewer downstream from this point was only 150mm wide.

Welsh Water responded, stating that they were in a position to approve the connection, but that it must be made at a different connection point. The point proposed by Welsh Water was 300 metres away, across third party land, where the public sewer had widened out to 300mm. Barratt would have to bear the cost of the link between the development and the connection point proposed by Welsh Water. Welsh Water argued that if the connection was made at its point, it would not overload the public sewer. Barratt argued that this was not a valid reason for which Welsh Water could refuse consent under section 106, since it did not relate to the mode of construction or condition of the private sewer.

In the meantime, the local planning authority discharged the planning condition, based on correspondence that Barratt had obtained from OFWAT. Barratt was therefore able to begin development.

The Supreme Court ruled that Welsh Water was obliged to deal with any discharge that was made into its sewers under section 106. If consequential works were required to accommodate the increased load on the public sewer, the cost of these works fell on the sewerage undertaker, and not the developer.

It was impossible to extend the natural meaning of "mode of construction" of the private drain or sewer in section 106 so as to include the point at which it was proposed to connect that drain to the public sewer. On that basis, Welsh Water was not entitled to refuse consent by reason of the proposed point of connection.

Things to consider

The court noted that this was the first occasion upon which a court had been required to resolve a dispute between a property owner and a sewerage undertaker as to the point of connection of a private drain with a public sewer. This indicated that the point of connection does not normally give rise to difficulty in practice.

The real problem, in the court's view, was not an owner's right to select the point of connection, but the fact that no objection to a connection can be made by a sewerage undertaker on the ground of lack of capacity. Section 106 gives an absolute right to an owner to connect a drain to the public sewer under section 106 on giving only 21 days' notice. The court thought that, while this created no problem in the case of an individual dwelling house, it was "manifestly unsatisfactory" in relation to a development which might increase the load on the sewer by 25% or more. The public sewer may well not have surplus capacity capable of accommodating the increased load without the risk of flooding unless the undertaker has received sufficient advance notice of the increase and has been able to take the necessary measures to increase capacity. The problem is accentuated by the fact that the budgets of sewerage undertakers are agreed at five-yearly intervals by OFWAT.

The court suggested that the problem could be resolved by the local planning authority making the grant of planning permission conditional upon the sewerage authority first taking any steps necessary to ensure that the public sewer will be able to cope with the increased load. In order for this to happen, the court thought that it was essential that there should be input to planning decisions from both the relevant sewerage undertaker, and OFWAT. The court stated that "more thought may need to be given to the interaction of planning and water regulation systems under the modern law to ensure that the different interests are adequately protected".

Barratt Homes Ltd v DWR Cymru Cyfyngedig (Welsh Water)