Reducing Wastewater Amounts to help your Septic Tank and Sewage Treatment Plant

Does reducing water consumption help your Septic Tank or Sewage Treament Plant?

sewage treatment plant or septic tank is designed to be able to treat a certain volume of sewage per day. At this design volume, the plant will treat the sewage for the minimum amount of time needed to achieve the treatment required.  If the flow rates are more than this, then the sewage will not be treated to the required standard.

Water Consumption Figures for the UK.
Each person in the UK uses 150 litres of water a day. This takes into account
cooking, cleaning, washing and flushing. This has been rising by 1% a year since 1930, with a big rise about 20 years ago. This consumption level is not sustainable in the long-term. British Water actually use the figure of 180 litres per person, allowing for this trend, though a new Goverment sustainability initiative requires all houses built from Oct 2009 to use no more than 120 litres/head/day.

Two of the biggest factors responsible for this increase in this water consumption are washing machines and dishwashers.  30 years ago, most washing machines were twin-tubs which used the same water over and over again as the whites were washed first, then coloureds, then the dirty work clothes.  This is no longer the case.  The same principle was used for washing up in a bowl - glases first, then plates, then dirty pans.

Some of the modern appliances use tremendous amounts of water and this is causing problems for sewage treatment plants, particularly as every load also contains vast amounts of detergents, softneners and salts.  It is possible to buy low water consumption models, but the energy rating usually refers to electricity consumption, NOT water usage.

How to reduce water consumption

We have taken the figures from 'Waterwise' which include water consumption (and energy ratings) for all the leading brands.  The tables are here. Please click on the link Washing Machine Rankings. 
By reducing wastewater amounts into the treatment plant, then the sewage will be aerated for longer and the effluent will be cleaner.

Waterwise has carried out some research and found that the energy used to pump, treat and heat the water in the average family's home produces the carbon equivalent of a
return flight from London to New York. Saving water will also help alleviate climate change and can make the water scarcity problem in another country less severe. So, even though we cannot help other nations by transporting our water to them, we can help them by reducing our water consumption.
Why save water

A running tap uses 6 litres of water a minute, a power-shower can use 45 litres per minute, a hosepipe uses as much as 100 litres per minute.

Toilet flushing accounts for 35% of our daily water use – Older toilets use up to14 litres per flush compared to new dual flush models which use as little as 2.6 and 4 litres per flush. 

A dripping tap can waste as much as 5000 litres a year.
How to save water

There are numerous ways you can save water. You can purchase water efficient products and install them and you don’t have to alter your habits in any way. However, there are also things that you can do for free which save water.
- Use low water consumption washers and dishwashers.
- Replace your power-shower with a low water consumption aerated showerhead model.


- Turn the tap off when you brush your teeth – a running tap wastes 6 litres of water a minute.

- Don’t use your toilet as a dustbin – Put your face wipes, cotton wool balls in your dustbin rather than down the toilet. If everyone in the UK who currently uses their toilet as a dustbin, stopped doing this, we would save 27 million litres of water a week – that’s enough to supply the population of York or Portsmouth for one day.

- Invest in a rainwater harvester - this can then collect some of the 90,000 litres of rain that falls on your roof every year. This water can be used to flush your toilet, wash your clothes, water your garden, clean your car and wash your windows

- Install a cistern displacement device in your toilet – these can be obtained free of charge from your water company and displaces water in your cistern so that the volume of water in your flush is reduced by between 1 – 3 litres.  You could also install an 'INTERFLUSH' device on you handle type toilet which allows an infinite amount of water to be used per flush.