Think of water pollution and you probably imagine factories ditching chemicals and other nasties into our rivers. So it might surprise you to know that much of the pollution is down to domestic customers like you and me. And that’s thanks to what’s known in the trade as ‘misconnections’ — sometimes ‘cross connections’. It means that household appliances are hooked up to the wrong kind of drain so that foul waste is discharged into a surface water network, which then runs into a watercourse.

With the prospect of this causing serious pollution, the utility companies are on the case. In the Bristol area, Wessex Water is running ‘Operation Stream Clean’ jointly with the City Council and the Environment Agency (EA) to identify offending properties. Thames Water (TW), meanwhile, has conducted a five-year investigation with the EA in North London and revealed that the equivalent of two Olympic-sized swimming pools of wastewater wrongly enters the region’s rivers and stream every day (wwtonline 8/4/15).

A survey of 2,600 homes around Finchley’s Strawberry Vale Brook, found 275 appliances emptying directly into the stream. In Muswell, a staggering 975 appliances were misconnected — including 26 toilets. TW concludes that illegal connection figures may be as high as 60,000 across its area, whilst Dwr Cymru Welsh Water estimates that some 20% of its domestic properties have some form of illegal drainage connection. These figures are from just two of the ten Water and Sewerage Companies (WaSC) in England and Wales. UK-wide, the number of illegal sewer connections must be a major cause for concern.

Understanding the sewer system

More often than not, it’s a case of mistaken sewer identity, so knowing the difference between a ‘storm’ or ‘surface’ water drain and a ‘foul’ one is crucial. The clue is in the name. Water (ie rain or snow) which lands on a surface (roof, patio, drive, roadway, etc) should run into the surface water (aka storm) drain. Wastewater from anything else (eg toilets, baths, showers, sinks, washing machines, etc) that contains contaminants (whether that’s human waste or detergents) should go into the foul sewer network.

Since the surface water network carries natural rainfall, it discharges directly into a nearby watercourse, such as a river, or the ocean if you happen to be beside the seaside. Foul waste, on the other hand, goes to a sewage treatment works to be dealt with.

Whilst they may not intend to break the law, householders (and sometimes plumbers and builders) installing a washing machine in the garage, for instance, will happily connect it to the nearest outlet — which may be a storm drain. And though plumbing innovations like saniflo might have allowed toilets to be fitted practically anywhere, they still have to discharge into the foul waste system. Misconnect and you could find yourself on the wrong side of the Environmental Act 1990, not to mention £20,000 poorer if you don’t then sort it out.

The consequences

Remember that the home or property owner is responsible, so if you’re buying new premises, it’s important to check that all your waste connections are hunky dory. Ignorance is no defence, and there may be far-reaching consequences if they are not. When a toilet is connected to a surface water drain, the contents are despatched, untreated, directly to the nearest watercourse (euw!). Not good for us, and not good for our wildlife either. Alarmingly, when oestrogen gets into the water via sewage and the female contraceptive pill, it also affects the reproductive cycle of fish. Hormonal impact on our marine life aside, raw sewage in our waterways is surely to be avoided at all costs. We may have moved on since the River Thames in London was like an open sewer so that politicians had the curtains of the Houses of Parliament soaked in chloride of lime to try and mask the appalling smell (thanks to BBC TV’s Horrible Histories for that snippet), but we still need to be vigilant about where our waste ends up.

Untreated sewage contains organic matter (carbohydrates, fats, proteins), bacteria and chemicals. Bacteria naturally present in environmental waters do break these substances down, but in doing so they use up the oxygen in the water. Continuous discharges of untreated urban wastewater therefore cause oxygen levels to drop drastically and sewage fungus to cover the bed of the watercourse like a blanket. In severe cases, the river is no longer able to support fish, insects and animals that live in and around it.

It’s not just about sewage in our rivers. Misconnect the other way round (a surface or storm water outlet into the foul sewer) and you could contribute to sewer flooding. In the sort of heavy downpours we’re experiencing more and more here in the UK, massive surges in surface water can push the sewer system to breaking point; that’s why a separate storm drain system was devised. So there is more than one reason to double check that all your drains are in the clear.

Tackling the issue

A UKWIR project (“Sewer Misconnections: What is the True Non-Agricultural Diffuse Water Pollution Impact? (13/SW/01/3)”) to determine the true scale of such misconnections, the options for identification and control and the environmental impact of polluted surface water sewer outfalls, concluded that around 13 million properties are served by separate sewer systems of which around 1% are likely to be misconnected. It also suggested that identifying these properties is likely to cost £190 million. According to the EA “..on average 9 per cent of the pollution at bathing waters comes from misconnected drainage, while 29 per cent comes from sewage and 35 per cent from agriculture.” (Utility Week, February 2014).

Although for around the last 60 or so years, there have been separate sewers for foul wastewater and surface wastewater, the integrity of the system has been compromised by misconnections, whether deliberate or otherwise. Putting illegal connections right is relatively simple, but tracking them down in the first place can be a costly and time-consuming business. Perhaps a new method trialled in Sheffield holds the key. According to WWT magazine (May 2015) engineers at the University discovered that the natural, untreated cotton of a tampon readily absorbs the chemicals known as optical brighteners which are used in toilet paper, detergents and shampoos. If dipped into water containing even 0.01ml of detergent per litre (300 times more dilute than would be expected in a drain), the tampon glows under UV light. Of 16 surface water outlets tested, researchers found tampons confirmed the presence of the chemicals in 9 cases. Working with Yorkshire Water, the team followed the network and used tampons again at individual manholes to see where sewage entered the system. Culprits were tracked all the way back to source — result!

However, obviously it is preferable that pollution is stopped before it starts. Speaking at the launch of ConnectRight, a campaign part-funded by the water companies, MP and Water Minister Dan Rogerson said: “Prevention is better than cure and if we can prevent new misconnections occurring then we will be winning the battle against water pollution and improving the water environment for generations to come.”

Lanes to the rescue

If you’re in any doubt, it’s straightforward to check that all is in order down below. Ask a reputable, local drainage company — like Lanes. We’ll carry out a full CCTV survey which will not only reveal the condition of your drains and any faults and potential blockages, but also show up any misconnections.

Typical prices for our homebuyers’ surveys range from £200 for a terraced house to £300-£350 for a detached property. What’s more, you don’t have to wait long: all our depots have the operatives and equipment to undertake survey work, usually within three days, whether that’s the small units designed for domestic drains or the large crawler CCTV systems for larger diameter pipes. And of course, we can rectify any problems with the drains as well as put right any misconnections. This can usually be done without local authority permission, as long as it’s not a direct connection into the carrier drain. In that case, you would need someone with RSWA certification. But then, guess what? We have those people too.

For our commercial and industrial clients, we maintain drainage systems and empty interceptors, bunds and tanks as a registered waste handler. We also help you meet IPPC (Integrated Pollution Prevention and Control) legislation and ISO14001 environmental standards, with the market-leading Aquasentry range of pollution prevention, monitoring, spill control and clean-up solutions.

If you think you may have an illegal connection or just want to make absolutely sure you haven’t, talk to Lanes on 0800 526488. When it comes to drains, we really are all you need to know.

Further Information

For more information about illegal sewer connections, visit the Connect Right Campaign (http://www.connectright.org.uk) supported by Water UK, the Environment Agency, the Consumer Council for Water, The Chartered Institute of Environmental Health, DEFRA and the Chartered Institute of Plumbing and Heating Engineering. Or check with your local Water and Sewerage Company.