Lead gets into drinking water from old pipes and fittings, not from the water source itself. Millions of older UK homes were built with lead water pipes, and some still have them. There is no known safe level of lead exposure, so if your home might have lead pipework, it is worth finding out and dealing with it.
At a glance
- UK limit: 10 µg/l at the consumer's tap
- Most at risk: homes built before 1970, especially in soft or acidic water areas
- Signs: none in the water itself; look at the pipe by your stop tap
- Fix: replace lead pipework; reverse osmosis for drinking water in the meantime
How lead gets into tap water
Lead was widely used for water supply pipes and internal plumbing until it was banned for new drinking water pipework in 1970. Lead solder was also used on copper pipe joints until the late 1980s. Lead slowly dissolves into water that is in contact with it, and more dissolves when:
- Water has been standing in the pipes for several hours, for example overnight or while you are away.
- The water is soft or acidic. See acidic water; this is a particular issue on private supplies, which receive no corrosion control.
- The water is hot, which is why you should never drink or cook with water from the hot tap.
Many water companies add a small amount of phosphate to mains water, which forms a protective layer inside lead pipes and reduces how much dissolves. It helps, but it does not make lead pipes safe.
Why lead matters
Lead builds up in the body over time. Babies, young children and pregnant women are most at risk, as lead can affect a child's developing brain and nervous system. The legal limit for drinking water is 10 micrograms per litre, set by the Water Supply (Water Quality) Regulations 2016, and the Drinking Water Inspectorate encourages householders with lead pipes to replace them.
How to tell if you have lead pipes
- Find your internal stop tap, usually under the kitchen sink.
- Look at the pipe coming up from the floor into it. Lead pipe is dull grey, fairly thick and soft.
- Gently scratch it with a coin. Lead shows a shiny silver colour; copper shows bronze.
- Look at the joints. Lead pipes have rounded, swollen joints rather than neat compression or soldered fittings.
- Tap it with the coin. Lead gives a dull thud; copper and iron ring.
Even if the visible pipe is plastic or copper, there may still be lead elsewhere, under the floor or in the supply pipe running to the boundary.
Who is responsible for replacing lead pipes?
Your water company owns the communication pipe up to your boundary, usually to the outside stop tap. The supply pipe across your land and everything inside the house are your responsibility. Some water companies will replace their section free of charge, or offer help, when you replace yours, so contact them before starting work.
Testing for lead
Because lead levels depend on how long water has stood in the pipes, sampling has to follow a set method. A laboratory tap water and lead test gives a reliable answer for your tap, and our results guide explains the figures.
Reducing lead in your water
- Replace the lead pipe. The only permanent fix. Replace both your supply pipe and any internal lead pipework.
- Until then: use only the cold kitchen tap for drinking and cooking, and run it until it is noticeably colder before using it, especially first thing in the morning.
- Filter drinking water. A reverse osmosis system with its own drinking water tap significantly reduces lead and other dissolved metals.
- Private supply? Correct acidic water with pH correction so it stops dissolving metals from your plumbing.
Related contaminants
Why Wrekin Water
Wrekin Water is a family run company based in Bettisfield, Shropshire, serving more than 50,000 customers over 15 years and rated Excellent on Trustpilot. We supply reverse osmosis and drinking water systems nationwide and install them in North Shropshire. Ask our team which system suits your home.