The proposals are intended to fill a gap in the law which was exposed by a court case in March 2000. Before then, local authorities had successfully tackled odour pollution problems from sewage works by serving abatement notices under the statutory nuisance provisions of the Environmental Protection Act 1990.
However, that option was closed by the court case when Yorkshire Water appealed successfully against an abatement notice. The court agreed with the company that sewage works are not covered by the statutory nuisance regime because they are not "premises" within the meaning of the Act.
The ruling has defeated several subsequent attempts by local authorities to deal with serious odour problems.
Some 8,000 residents are now seeking civil damages of around £5,000 each from United Utilities in an action under the Human Rights Act. Meanwhile, the company is investing £22 million in a project to cover part of the works to enable odorous emissions to be collected and treated.
Thames Water's promise that the problem would be remedied by a £20 million refurbishment of the works' sludge digesters has so far failed to deliver. On the day that DEFRA published its consultation paper, the company announced that a further £2 million will be invested in measures to tackle the nuisance directly.
Residents' groups around these works and a fourth in Leith have linked up to campaign for a change in the law. The Seafield works in Leith is a private finance venture run by Stirling Water in which Thames Water is a partner, and also faces civil action under the Human Rights Act.
DEFRA's consultation paper puts forward four options:
Potential drawbacks, the paper notes, would be that different odour control standards might be required by different local authorities, and magistrates' courts might come to different conclusions about whether a particular odour control method constituted the "best practicable means" - the key defence against an abatement notice.
However, the paper makes no reference to the other potential environmental benefits of this option - nor to the possibility that bringing all sewage works under IPPC might make them eligible for a climate change levy agreement and an accompanying 80% discount on the climate levy, which the water industry has long been lobbying for.
The latter two options would be the most expensive for water companies and their customers, with odour control costs having to be incorporated in the five-year price-setting process for the industry. DEFRA has promised to publish shortly a full regulatory impact assessment of all four options.