If you live in Southampton, Eastleigh, Winchester or much of Hampshire, you will know about limescale: the white crust on taps, kettles and shower screens. Hard water is common across the area, and it affects your wastes and drains too.
What hard water is
Hard water contains dissolved minerals, mainly calcium and magnesium, picked up as rainwater passes through chalk and limestone. In much of Hampshire, the water supply comes from chalk aquifers and chalk rivers, which is why it is hard. Your water company can tell you how hard the water is at your postcode.
How limescale affects drains
- Narrower wastes and traps. Scale builds up inside basin, bath and shower wastes and traps, reducing the space for water to flow.
- Rough surfaces. Scale gives hair, soap and grease something to cling to, so blockages form faster.
- Soap scum. Hard water reacts with soap to form scum, which combines with hair in showers and baths.
- Appliance discharge. Washing machines and dishwashers can contribute to scale and soap build-up in shared waste pipes.
Showers and basins are usually affected first, because of the hair and soap. See how to unblock a shower drain and why is my bath draining slowly?
Signs limescale is part of the problem
- Wastes and plugholes with a white or grey crust
- Showers and basins that slow down gradually, even when you clear the hair
- Gritty, chalky deposits in traps when you clean them
Keeping limescale under control
- Clean wastes and traps regularly, removing scale with a suitable descaler. Follow the product instructions, and do not mix it with other cleaning products.
- Use hair catchers in showers and baths.
- Run hot water for a minute after using basins and showers.
- Consider a water softener or scale reducer if scale is a problem throughout the house. Ask a plumber which type suits your home.
When it is more than limescale
Scale on its own rarely blocks an underground drain, but it often plays a part in blocked wastes. If cleaning the trap and waste does not fix a slow fitting, the blockage may be further down. Professional drain cleaning or drain jetting removes build-up from the pipes.
See also blocked showers and blocked sinks.