Will supermarkets influence our water conservation?

Tomorrow’s opening of Sainsbury’s most environmentally friendly, zero carbon, waste and water neutral store in Leicester, sourcing  70 per cent of its water demand through rainwater harvesting presents an interesting model.  Is it enough of an example to persuade Mr & Mrs Jones to adopt a similar approach at home?

In a large national survey of water use in and around the home, published in a Report for Consumer Council for Water in Associate with WRc, residents were asked what would be the most likely reason to make you conserve water.  The results revealed the following influences:

  • If water companies conserved water 21%
  • If water-efficient devices were cheaper 20%
  • If it was easy to get information on how to conserve water 13%
  • If someone came round to my house to install water-efficient devices 11%
  • If it was easier to buy water-efficient devices from a local shop 7%
  • If I was reminded of water efficiency when I was deciding on an appliance 6%
  • If I had a better understanding of the impact on the local environment 6%
  • If children were educated about water conservation 6%
  • If someone talked to me to make it clear that water conservation is important 5%
  • If I understood and had confidence in a water-efficiency label on a water appliance 3%
  • Other 1%

Source: Report for Consumer Council for Water in Association with WRc

Other items that respondents identified included: compulsory water meters, if businesses conserved water; if my bill got higher and if I thought it would make a difference.

The majority of reasons listed above are not insurmountable, and most could be achieved without the need for any legislation.  The immediate hurdle seems to be the reluctance on the part of individuals and households to adopt a more water efficient mentality.

Not surprisingly, most felt that water companies do not do enough to save water, stating that they would definitely/maybe do more to save water if they perceived that the water companies were doing their bit as well.

Some of the UK’s Water companies are now beginning to address their widely reported leakage problems, which hopefully will unlock the door and encourage more individual involvement at residential level.

It would seem from the survey that most people would not need to be forced to conserve water.  People need to be encouraged to make savings, through education, with Water Companies setting an example for us to be more water conscious and use water efficiently.

Whatever the solution, it will be a carefully coordinated and collective effort that needs to be encouraged and will win the day. Certainly more action such as the Sainsbury’s initiative can open the door through which others will follow.


Reducing reliance on mains water with rainwater harvesting

Installing rainwater harvesting systems can provide a variety of benefits, financial as well as reducing the risk of flooding in some areas.

However, it may not be suitable for every installation, and needs some careful thought and assessment beforehand before committing to any expenditure.

Rainwater harvesting is very simple, and has been practiced for centuries.  Rainwater is collected from a clean surface (i.e. a roof), filtered, stored and reused.  It is a system used by millions of people around the world who don’t have access to a mains water supply.  In Germany, harvesting rainwater is widely practised with approximately 60,000 systems installed a year.

In the UK, rainwater harvesting is not so straightforward, and depends upon the location and end use.  The financial benefits depend upon the cost of the mains water which is relatively cheap compared to parts of continental Europe.

To establish whether a rainwater harvesting system will benefit your residence or business follow the basic steps set out below:

1.  Quantify the amount of water you currently use
– simply done by checking recent water bills

2. Quantify the maximum water you can harvest in a year
– based upon rainfall in your area, the area at the installation (house or business) over which it can be collected.

Annual rainwater yield (Y) in m3 = P x A x 0.8

Where P = annual precipitation (in metres) and A = collection area (m2)

0.8 = typically you should expect to collect approximately 80% of this water each year, due to small losses in filtering and small rainfalls that do not generate enough run-off.

3. Quantify the cost
Check water bills to assess current cost, and possible saving

Water quality is an important consideration depending upon the reuse application. Water for general domestic use such as WC flushing or irrigation of gardens, can be of a lower quality than that required for any application relating to food processing etc.

The table below illustrates the amount of water you could save, based upon the collection area.

A guide on the amount of water you could expect to save save, based upon the collection surface area

A guide on the amount of water you could expect to save save, based upon the collection surface area

A little film about water

I like this informative little film, it says exactly what I think about the way in which we need to start thinking about and treating our water supply

Education and inspiration

WWT Cartoon

One of my previous blog posts, Become an Agent of Change highlighted the need for each and everyone of us as individuals to rise to the challenge and to make a difference.

Our participation is fundamental to any long term change in the UK where potable water remains relatively cheap.  No end of measures are available that can and should be put in place to alleviate the ever increasing demands on our natural water resource.

Some of these have already been accepted and adopted, and are having the desired effect in industry and business sectors.

Guidance published by the World Business Council for Sustainable Developments (WBCSD) assisting businesses to understand the value of water and how they manage their water use is having a significant impact, reducing water stress and maintaining the sustainability of future operations.  Delivering this ideal will rely on closer collaboration and partnerships between local authorities and businesses.

However, even with the technology and measures available, the main challenge remains… how to get the ordinary householder to understand and appreciate the value of water and to adopt many of the measures available… where indeed is the incentive?

Rainwater harvesting and Greywater reuse are all well and dandy, but where is the incentive to change and adopt what could be an expensive solution in some cases.  With paybacks of 20 years or more on residential properties, it is unlikely that Mr & Mrs Jones will ever be encouraged to install a system (whether it be RWH or Greywater) that will most certainly reduce the dependence on mains water, but will take a generation to pay off.

In the UK where water is still relatively cheap compared with other parts of Europe, measures will need to be implemented to encourage more efficient use.  The knack is to change people’s attitudes without imposing legislation.

In the longer term perhaps, it has been suggested that all households customers should be metered where practical, particularly in water stressed areas, to encourage users to adopt efficient methods and water efficient appliances in the home, indeed paying less if greater efficiencies are adopted.

Until then it is important that the real value of water is appreciated and highlighted, particularly in our younger citizens.

In this respect, education has a vital role to play if we are going to ensure the sustainability of future use.  Increased water efficiency and providing alternative sources will certainly help to reduce carbon emissions where implemented.

Much can, and is being done by water companies, and businesses to make efficiencies wherever possible.  More must be done, not just by developing new technologies, but by educating those who will be responsible for our future and the changes that are needed now to tackle the challenges to our precious resource in the long term.

Five facts about taking a shower

Our bathroom habits have changed over the years.  There was a time when we didn’t have the luxury of a bath or shower… so I’m told anyway.

It has been estimated that each day Britain ‘showers away’ more than two billion litres of water.  On average, each person takes 4.4 showers and 1.3 baths each week.  Showering has now become the largest use of water in the home.

Did you know?

1  The average UK shower is 8 minutes long and uses nearly as much energy and water as a bath.

2  Showering costs the average UK family £416 per year.

3  Young boys are the worst offenders for lengthy showers, spending an average of ten minutes drenching their pubescent pores.

4  Not surprisingly, women are better multi taskers than men.  Even in the shower, they brush their teeth, wash their hair and shave.

5  The average teenage girl takes nearly nine and a half minutes in the shower, costing her parents around £123 a year.  Young girls aged 12 and under tend to take short showers of around six and a half minutes.

Based on a Unilever study

Septic tanks and private wastewater treatment systems

Is the house you're looking to buy or sell on mains drainage? If not, you need to be aware of the regulations that apply

Is the house you’re looking to buy or sell on mains drainage? If not, you need to be aware of the regulations that apply

Is your house on mains drainage? If not, then it is likely that your property has a cesspit, septic tank, or small wastewater treatment system.

If this is the case, then you need to be aware of the regulations that exist and apply to such systems, by the Environment Agency.

If buying, or selling a property with such a system, you will need to be sure that the system as installed has been sized correctly, and will enable the effluent to be treated satisfactorily and to a sufficient standard to enable the requirements by the Environment Agency to be met.  You should check whether it has been registered or is exempt.

Currently, and pending the outcome of a review for small sewage discharges in England, the Environment Agency will not be pursuing registration where the:

• discharge is to ground and is of 2 cubic metres per day or loess via a septic tank and infiltration system (soakaway) and is outside a Source Protection Zone 1 (SPZ 1)

• discharge is to surface water and is of 5 cubic metres per day or less via a package sewage treatment plant.

• sewage if only domestic

• sewage system is maintained in accordance with the manufacturers instructions and you keep a record of all maintenance. In the case of septic tanks this includes regular emptying and

• discharge does not cause pollution of surface water or groundwater

These are the main requirements that need to be checked, there are however other more detailed requirements, including the proximity of the house to foul sewers, tidal waters, conservation areas.

The requirements for systems discharging within a SPZ 1 require particular attention and should be checked out prior to installing a septic tank discharging to ground.

The requirements in Wales are not subject to review, and the existing registration system will remain in place.

Notwithstanding the requirements of the Environment Agency, you still have the option to register a small domestic sewage discharge due to a house sale.

It is important, whether selling or buying, that you ascertain that the system is adequately sized for the property being considered, as this can cause problems later and lead to additional costs that may not have been budgeted for at that time.

I recently undertook a survey of such a system where the septic tank had been designed and installed to serve the 4 bedroom property on site.  However, it had not been sized to accommodate the additional flow arising from a more recent barn conversion into 2 holiday lets, which was located on the land occupied by the main house.

Needless to say the inadequate size of the septic tank was a matter for much concern and presented a stumbling block in terms of the sale and the regulations that existed at the time.

Lights, camera, environmental action!

Well, what does an environmental engineering consultant look like?

This short film introduces me, Jeff Hughes, a chartered civil engineer with more than 30 years’ experience in waste water management and treatment.

Please do feel free to get in touch to discuss your commercial or domestic water conservation or treatment concern or issue – or to tell me what you think of the film, if you like.

An alternative approach to reed bed design


Reed beds have and always will provide a simple, effective and “natural” way of providing basic treatment. However, it must be appreciated that they are not a panacea

Reed beds were mainly used and seen as a process of reducing the level of biochemical oxygen demand (BOD) and suspended solids in sewage effluent.

Over the years, they have been increasingly used for other forms of treatment, and are currently being considered as an alternative solution for phosphorous removal in small sewage treatment plants.

Phosphorous is a limiting nutrient for plant growth in order to avoid eutrophication in lakes and rivers.

The process is viewed as a sustainable solution, due to its capacity to operate on low to almost no energy input, using only the hydraulics associated with gravity.

However, to achieve the levels of phosphorous being considered by the Environment Agency in certain areas, the extent of the reed bed required is proving significant, requiring a substantial area and involving in some cases the purchase of additional land outside the existing sewage treatment works, many times greater than that occupied by the works itself.

The removal efficiency of phosphorous depends upon the type of media used, which can vary between gravel, steel slag, etc.

Recent research suggests that the phosphorous is removed by chemical action as the principal process. However, this is limited to the composition of the media.

There are still unanswered questions that may require further research. Such questions are: what to do with the media after it has reached saturation, including safe disposal, also the durability of the bed and media replacement costs, all of which need to be taken on board and included in any cost comparison.

Reed beds have and always will provide a simple, effective and ‘natural’ way of providing basic treatment. However, it must be appreciated that they are not a panacea, and based upon the research carried out to date with respect to phosporous removal, to extend their treatment capability as an alternative solution in place of the more established systems, needs to be approached with some caution.

If it ain’t broke…

All too often in the past we have visited sites of wastewater treatment works, whether domestic or commercial, where the client has been poorly advised, or told that the best option is to replace with new.

Now the internet is a wonderful tool, but sometimes it may not provide you with the most appropriate or cost effective solution to your problem, and may at the end of the day cost you a significant amount of money, when you didn’t really need to spend much at all.

We recently visited a pub that had been provided with a wastewater treatment plant, and for some reason was giving rise to problems, particularly odour.  Not the sort of thing one wants wafting around the beer garden on a hot summer’s day.

The landlord had approached a number of suppliers who had suggested replacement of either part, or the whole of the treatment system.

It has always been our philosophy to work closely with the client, in order to assess and determine the problem, and to find the most appropriate and cost effective solution, whatever that may be.

After a fairly brief visit we were able to identify the problem, and recommend a solution that did not entail the replacement of the treatment plant, and that cost the client £100s and not £1,000s.

In this case, we were able to modify the existing plant.  The treatment of sewage can be achieved by a wide variety of treatment methods, no single approach being suitable in all situations.

‘Green’ is a wonderful concept, but it is not a panacea and in pursuing a ‘green’ option you should be wary of some manufacturers unsubstantiated ‘green’ claims.

The moral is, that only by employing an independent wastewater expert, can you be sure that you are getting and paying for the right solution.

Two reasons to invest in water infrastructure

Two simple yet compelling reasons for global investment in water infrastructures

1. Global water demand will increase by 55% by 2050

2. Without improvements to water management, the world could face a 40% supply gap by 2030

Source: World Business Council for Sustainable Development (WBCSD)


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