Will London run out of water?
As the capital faces growing water stress, the question of long-term water security is more pressing than ever. With demand rising and infrastructure under pressure, buildings that reduce reliance on mains water are key to a more resilient future. Vacuum drainage systems offer one promising solution.
Rising water stress in London
Across the UK, and especially in London and the South East, the risk of water shortages is increasing. Population growth, climate change and uneven rainfall are putting strain on existing water supplies.
Londoners currently consume around 149 litres of water per person per day, nearly 10 litres above the national average. During dry spells in 2006 and 2012, temporary restrictions on water use were imposed. And as pressures mount, the risk of further limits, or even disruptions, is becoming more real.
Even short-term water outages could lead to serious social and economic consequences in a city as densely populated and complex as London.
The London Plan and Water Efficiency
To secure long-term water sustainability, the London Plan sets clear expectations for developers. All new residential buildings must be designed to limit mains water consumption to 105 litres per person per day.
Reducing the use of potable water for non-essential purposes, such as toilet flushing, plays a central role in achieving this target.
Zero potable water for toilet flushing
An effective way to meet these goals is to combine vacuum toilets with rainwater or greywater systems. These systems are already in place in parts of London and enable the reuse of water from showers, basins and rainfall to serve toilets, with no use of drinking water at all for flushing.
Vacuum toilets enhance this approach by using only 1 litre or less per flush, reducing water consumption by up to 90% compared to traditional toilets. The combination of low-flush volumes and recycled water delivers a significant reduction in overall building water use.
How vacuum drainage supports water efficiency
Vacuum toilet systems offer several advantages beyond just reducing water consumption:
- Elimination of potable water use for toilet flushing when combined with water recycling
- Preservation of clean water resources in water-stressed urban areas
- Reduced strain on public infrastructure, thanks to lower discharge rates and volumes
- Lower costs related to water supply and drainage
These systems are already widely used in sectors like transport and marine, and are now increasingly being adopted in both commercial and residential developments.
A modern alternative to gravity drainage
Modern vacuum drainage technology is a reliable and efficient alternative to traditional gravity-based systems. With performance levels on par with standard toilets, they are well suited to contemporary buildings where sustainability is a priority.
For London’s future buildings, this means not just a reduction in environmental impact, but also long-term resilience in the face of growing water challenges.