Is there lead in my water?

Lead isn’t normally present in raw, untreated water sources (rivers, lakes, reservoirs) but significant concentrations can be found in drinking water if lead service (communication and supply) pipes, or copper pipes with lead solder joints and occasionally domestic water fittings, have been used in the domestic plumbing system.

The maximum Prescribed Concentration or Value (PCV) for lead is 10 microgrammes per litres (10ugPb/l). We must meet a strict standard on the level of lead in drinking water.

When water lies in contact with lead service pipes, lead-lined tanks, or lead solder, particularly for longer periods (e.g., overnight), lead can dissolve into the water during these periods of stagnation. The longer time that water lies in contact with lead, the more lead can dissolve in the water.

The main risk associated with lead is the potential effect that it could have on the intellectual development of children. Young and unborn children are therefore considered to be at special risk. For this reason, it is important that we keep lead levels in drinking water down to the lowest level, particularly for those special risk groups.

The health risks associated with exposure to lead are well known and understood. Lead is a harmful toxic heavy metal; its toxicity most frequently results from ingestion (drinking or eating) or inhalation. Exposures to high levels of lead can have adverse effects on human health.

Short term exposure to high levels of lead can cause a metallic taste and symptoms of abdominal pain, sickness, loss of appetite, low blood pressure, kidney and liver damage.

Long term exposure may cause headaches, irritability, tiredness, muscle fatigue and can affect brain development in the unborn and children up to 10 years old. Those pregnant and young children are therefore more at risk from lead than adults, although lead poisoning can occur in adults which can lead to serious illness.

Lead is a cumulative toxin meaning that concentrations of lead within the body, especially in the teeth, bones and some internal organs, can build up over time. It is therefore sensible to ensure that exposures to lead are kept to a minimum.

The use of lead pipes was phased out in the 1960’s and made illegal to install in 1969. Modern pipes are made of blue plastic (medium density polyethylene or MDPE).

None of our water mains are made of lead, and water leaving our supply works doesn't contain lead. There may be some remaining lead gaskets (joint sealing rings) in some older water mains.

Modern service pipes (made up of the communication and supply pipes that bring water into your property from the water main) are made of or MDPE. Some properties built before 1970 may still have lead pipes in them, or connecting them to the water mains, but properties built after 1970 are unlikely to.

If a lead pipe is damaged, flattened (which can happen when driveways and paths are replaced) or of an age where it starts to breakdown, the amount of lead in drinking water can increase. As well as lead supply/communication pipes, lead can also enter water through lead solder joints, lead-lined tanks or plumbing fittings.

If you live in an older property you may still have some lead plumbing present. You may already know if you have a lead service pipe or a lead-lined storage tank within your property. Even if you have already replaced your internal plumbing, it is important to check if any underground water pipes in your garden or driveway are made of lead.

Phosphate treatment, to prevent lead dissolving from pipe work (known as plumbosolvency), is installed at a number of our water supply works. We sample and analyse water regularly at our water supply works, service reservoirs and at our customers’ taps, and when sampling specifically for lead, we may take a first draw sample (first thing in the morning) and a flushed sample.

To identify lead pipes, look at the pipes leading to your kitchen tap or internal stop-tap (usually under the kitchen sink):

• unpainted lead pipes are a dull grey colour and relatively soft compared to other metals (e.g., copper) but show the shiny metal beneath when scraped gently; tapping a lead pipe with a metal object produces a dull 'thud' rather than a clear ringing.

Even if internal lead plumbing has already been replaced (usually with copper), it’s important to check whether any underground water pipes in your garden or driveway are made of lead, as these are the property owner's responsibility. To do this, check the pipe coming from your outside stop tap to your property (you might want to ask for help to do this if access is difficult). Usually, as well as the above, external lead pipes:

• are about 25mm (1 inch) in diameter
• have a rounded swollen joint where they connect to the stop-tap or meet other pipes.

If there's no lead pipe work, you'll see pipes made from either:

• copper (hard, bright or dull brown)
• iron (very hard, dark grey or rusty)
• polyethylene (coloured blue, black)
• PVC (grey) pipes.

Lead can dissolve in your water supply from (lead) soldered joints in domestic copper pipe work. Although lead solder for these types of joints was prohibited in 1987, there is evidence that lead solder is still sometimes used illegally.

Although the use of lead solder for drinking water pipe joints was banned in 1987, lead solder is still sometimes used illegally, so always use a trusted WaterSafe) plumber.

Lead lined storage tanks may also still be present in some older properties. If the drinking water tap in the kitchen is supplied from a household storage tank, we strongly advise updating it to connect directly to the mains and recommend replacing any lead lined tanks.

If you think you have lead pipes and want to confirm this, call us on 0330 303 0368, and we can arrange to come and test your water for presence of lead, free of charge. If our tests show that the level of lead in your drinking water is higher than the legal limit (the PCV) we have processes in place the resolve the problem. If it is decided replacement is necessary, we will replace the communication pipe and offer to replace up to 10 metres of supply pipe free of charge.

When replacing lead plumbing, the permanent solution is to replace all lead pipe work with pipes made from safer materials. Remember:

• copper and lead pipes should never be used together
• lead solder shouldn't be used on copper pipe joints for drinking water
• if alternative, non-metallic pipe work is used, electrical earthing should be checked by a qualified electrician.

If analysis of samples shows the concentration of lead is greater than the PCV, we’ll remove any sources of lead from our pipe work and advise you on replacing the affected parts of your domestic plumbing system. We will also provide flushing advice to protect public health. Remember, we will also offer to replace up to 10 metres of supply pipe free of charge. The responsibility for replacing any internal domestic lead pipe work lies with the property owner.

If you've identified lead pipes in your property, we always strongly recommend replacing them as soon as possible.

If you do need to use lead pipes, don't drink the water that has been standing in the pipes overnight:

• first thing in the morning, run the tap for about one minute (instead of wasting water, fill a bowl to water plants). If you have a long supply pipe you may have to flush for longer; as a guide, run your tap an extra 15 seconds for every extra 10 metres of supply pipe to the water main.
• run the mains fed tap (cold kitchen tap) for a minute if the tap hasn’t been turned on all day – for instance, if you’ve been out at work.
• always run the tap before making up bottle feeds for infants.
• ensure that the cold kitchen tap is fed directly from the water main, not from a storage tank.
• always use water from the cold water tap for drinking water or cooking. Hot water dissolves lead more quickly than cold water and is therefore more likely to contain greater amounts of lead. If hot water is needed for drinking water or cooking, water should be drawn from the cold water tap and heated. Use only thoroughly flushed water from the cold water tap for drinking and when making baby milk formula.

If there is a level of lead in your drinking water (determined by sampling and analysis) it is most likely to be due to the service pipes to your property. Service pipes are the pipes that carry water from the water main in your street direct to your property. The service pipe is made up of two parts – the communication pipe and the supply pipe.

Southern Water is responsible for the water main in your street and the communication pipe up to, and including, the stopcock at the boundary of your property. The property owner is normally responsible for the supply pipe from the stopcock into the property and all of the indoor plumbing. Southern Water will offer to replace 10 metres of supply pipe, free of charge, when we replace the communication pipe.