How to Reduce Water Wastage

ABOVE: It’s not the first time a manufacturer has dabbled with the idea of a ‘basin toilet’, but Roca’s W+W is the first stylish solution. The all-in-one recycles waste water from the basin to fill the cistern — reducing water usage by up to 25% compared to a 6/3 litre dual-flush WC. roca-uk.com

Changes to Part G of the Building Regulations, introduced in April 2010, require that we use less water and that the temperature of water reaching a bath is regulated. While temperature arguably needs to be limited for safety – preventing children and the elderly from scalding themselves – it is sometimes difficult to understand why water needs to be saved. However, fairly simple changes in how we use water can be very effective.

Why Save Water?

According to The Environment Agency, we only have 1,334 cubic metres (m³) of water per person per year in the UK — much less than France (3,065m³) or even Mediterranean countries like Italy (2,785m³) and Spain (2,775m³). This is due mainly to population density but also to where the rain falls. South-East England has even less water per person and the Thames Valley has only 266m³ — a fifth of the UK average.

A running tap uses 6 litres (1,000 litres = 1m³) of water a minute; a shower can use anywhere between 10-45 litres per minute; a hosepipe up to 1,000 litres per hour. Old toilet cisterns use as much as 14 litres per flush; new dual-flush models use as little as 2.6 and 4 litres per flush.

Average UK consumption is 150 litres of water per person per day, about one third of which is wasted — flushed straight down the plug hole or the toilet. We use almost 50% more water than 25 years ago — mostly because we shower more often, use power showers and have more water-using household appliances. The figure is still rising by a steady 1% per year while annual average rainfall remains fairly constant.

How Much Must We Save?

The new Building Regulations 17K Approved Document G requires that the potential consumption of wholesome (potable) water must not exceed 125 litres per person per day, when calculated in accordance with the set methodology.

To put that in context, it is ‘potential consumption’ – not actual – and what we must save amounts to just two flushes of the toilet per day: less than one shower or only a third of a bath. The saving required is not huge and if dealt with sensibly will have little or no impact on how we actually use water — it just means cutting out some of the wastage.

A useful tool to calculate your potential water consumption is available at wrcplc.co.uk.

How to Save it

One way to save water is to fit devices like dualflush WCs, aerated taps and showers, A-rated appliances and smaller baths. These are not expensive fixtures, with a goodquality aerated tap adaptor, for instance, only costing around £9.

View a comprehensive list of watersaving devices at waterwise.org.uk. What these devices do is reduce the amount of water used – typically by introducing air to the flow – without changing the ‘user experience’, i.e. the shower makes you just as wet. A flow-restricted power shower may seem like an oxymoron but they exist, they work and they use about a third of the amount of water.

Fitting aerators or flow restrictors to baths and sinks has no benefit as a volume of water is wanted and these devices will only increase the time it takes to fill the bath.

Other options are rainwater harvesting or greywater recycling. Since the Water Industry Act 1991 allowed the use of non-wholesome water (greywater or harvested rainwater) for certain applications, the industry has bloomed.

Essentially, fit a greywater recycling or rainwater harvesting system for toilet flushing, laundry and outside use and the new requirement is virtually met. The capital cost for either option is broadly the same at £1,500 to £4,500 depending on the size of the house, but using both is seldom necessary.

It is important that we use water wisely all the time and not just during a drought, as we are not alone in our need for water. We are a small island with a lot of people but our flora and fauna also need water. We need to make sure that we have enough and at the same time protect our natural environment, now and for future generations.

"Rainwater Harvesting can play a huge role"

Expert Michael Farnsworth, Director of Stormsaver, offers his advice (0844 884 0015; stormsaver.com)

The alterations to Part G have placed significant emphasis on the need to save and reuse water. The regulations limit water usage to 120 litres for inside use and five litres for outside use per person, per day.

Looking at water re-use and recycling, no matter what the budget, there is always something which can be done. A water butt starts from around £10 and can provide up to 100 litres of water — perfect for gardening. At the other end of the spectrum, rainwater harvesting and greywater recycling systems can play a huge role in reducing a property’s reliance on mains water, reducing people’s utility bills and making the most of a natural resource.

Rainwater harvesting systems, like MonsoonÆ from Stormsaver, collect rainfall, filter it and direct it to the point of use — washing machines and toilets or outside taps. The MonsoonÆ system uses very little power and, in optimum circumstances, can provide around 50 per cent of an average family’s water needs and up to £155 savings a year (dependant on rainfall and roof area).

Greywater recycling is another option. Here, waste water from domestic appliances such as baths, dishwashers and washing machines, is captured and used in other applications, such as toilet flushing. This type of system is ideally suited for use in properties with a limited roof area, but the maintenance requirements and running costs are higher than that of rainwater harvesting systems.

Prices for rainwater harvesting systems will vary from property to property and the amount of rainfall in the area. The MonsoonÆ system from Stormsaver starts at £1,500.

Further Reading: 

• Green Technology: Water Recycling 
• Solar Panels for Hot Water
• 6 Steps to an Energy Efficient Home