Protecting water quality in premises and mains

Is the enforcement of the Water Fittings Regulations a bureaucratic burden or essential to protect and save?
Definitely the latter, says Steve Tuckwell, managing director of the Water Regulations Advisory Scheme

In the UK within the last ten years drinking water has been contaminated by untreated farm borehole water which turned your hair green when you washed it; corrosion inhibitor from a central heating system, a health risk to the unborn foetuses; faecal bacteria from a rainwater harvesting system; bilge waste from a docked ship; faecal solids from neighbours’ toilets; final effluent from the local sewage works.

In all these cases, the water supplier distributed wholesome drinking water that then became contaminated by backflow or cross-connection. The consequences are not just a horrible mouthful of water to be spat out, some 600 people were affected and six were hospitalised with a kidney-damaging bacterial infection when an industrial cross-connection drew contaminated stream water into a village’s public supply. People understand that gas and electricity can kill you if not handled correctly, but water supplies are seen as harmless. Yet coroners inquests have found that breaches of

the Water Fittings Regulations has been partly responsible for deaths.


Installers and users of plumbing fittings fed from public supplies have to comply with the Water Supply (Water Fittings) Regulations and Scottish Byelaws, which protect against contamination of drinking water and promote water saving. Each water supplier has the legal duty to enforce them in its area of supply.

Regulations staff receive details of proposed plumbing installations from developers, check them for compliance and issue consent for installation of correct designs to proceed. Water suppliers inspect the plumbing systems in a proportion of new and existing domestic and non-domestic premises, from the supply pipe at the boundary to the farthest taps and appliances.

Where infringements are found, improvement notices are issued and followed up to ensure corrective action is taken. Until serious contamination risks are removed, the supply can be disconnected.

Backflow risk
Water suppliers’ inspectors find high numbers of serious backflow contamination risks in all types of premises (see table). The nature of the contaminants represents a ‘significant’ or a ‘serious’ health hazard.

Water suppliers and plumbers’ associations have promoted installers competency schemes (Approved Contractors Schemes) and around 20,000 members have demonstrated their knowledge of the regulations. Despite this, substantial contraventions are still found in new premises.

Once the property is occupied, changes made can add to the infringements, so the problem is much worse in existing premises. Partly this is due to repairs and refurbishment being carried out by untrained ‘handymen’ or DIY-ers.

Backflow is not a theoretical risk. For backflow into water mains to occur, a reduction in water pressure is needed, as happens with burst mains, planned maintenance, fire fighting, illegal use of hydrants and high demand for water.

Mains pressure loss is estimated to occur in England and Wales on average once a minute and with over 5M infringement risks out there, backflow is waiting to happen. Water suppliers hear of backflow incidents either when someone in the premises where it is happening complains about poor water quality – unaware of the cause – or from neighbouring properties when the backflow affects them via the mains. From reports received by a sample of water suppliers, it is estimated that in England and Wales, 102 backflow incidents have contaminated drinking water in eight years.


The legal duty of water suppliers to enforce the Regulations is itself enforceable by the regulators, whose ultimate sanction is the temporary or permanent revocation of the supply operating licence. A serious backflow incident could contaminate water supplied to other premises via the water supplier’s mains.

The water supplier’s only defence against prosecution by the Drinking Water Inspectorate (DWI) for breach of the duty to provide wholesome water is that it took all reasonable steps and exercised all due diligence to maintain wholesome supplies.

In deciding whether all ‘reasonable steps’ were taken, the DWI assesses whether the generally effectiveness of the water supplier’s enforcement of the regulations, and how it had enforced backflow prevention at the premises where the backflow occurred.

Without adequate enforcement of the regulations, the water supplier’s only line of defence has gone, increasing the likelihood of conviction. Senior staff also have personal liability and could be convicted under the Water Industry Act if an offence was committed with their consent or connivance or was attributable to their neglect.

Drinking Water Safety Plans
The DWI chief inspector’s report every year has examples of bad plumbing causing contamination of drinking water. The DWI promotes use of Drinking Water Safety Plans (DWSPs) to assess the risk to drinking water quality once it passes from the mains into the plumbing systems in premises.

The safety plan includes understanding how hazards enter the water supply, identifying risk control measures and monitoring their effectiveness. Water suppliers assist the owners of premises, local authorities, local Health Protection Units and plumbing and maintenance service providers to undertake risk assessments of premises’ water supplies.

The Water Fittings Regulations are the essential control measures in premises’ DWSPs. Their effective implementation and enforcement can protect quality in premises better than any other single means.

Water conservation
Prevention of waste, misuse, undue consumption and erroneous measurement of water are the remaining purposes of the Water Fittings Regulations. The regulations saved water by reducing the maximum permitted flush volume for new WCs from 7.5 to 6 litres and re-introduced dual flushing. WRAS negotiated permitting retro-fitting of dual and variable flush devices to the larger ‘byelaws’ WCs, which flush over 7.5 litres.

Water suppliers enforce the duty on owners of plumbing systems to maintain them in working order. Where necessary they prosecute for wasting water, as the recalcitrant householder found when faced with £700 fine and costs for not repairing a leaking WC cistern. Some Suppliers have accepted an Ofwat target to achieve annual water savings by enforcing rectification of regulations contraventions and by making water-saving recommendations.

These water audits can help a water supplier’s relations with customers during inspections by offering some potential savings to offset the cost of rectifying contamination risks.

Inspections can also identify illegal connections which deprive the water supplier of revenue, such as the 20 domestic supply connections found on an un-metered fire main. Enforcement of the Water Fittings Regulations and Scottish Byelaws by water suppliers fulfils a legal duty, but delivers so much more by protecting water quality within premises and in the supplier’s main, protecting the supplier against possible prosecution and bringing water savings by waste control and efficient use of water.

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