Making waste water the newest taboo
Although water utilities have made great strides in reducing leakage, wasting water needs to become the next big social ‘no-no', ABB electromagnetic flow product manager Alan Hunt writes
This year, ‘flaming June’ singularly failed to live up to its reputation, with drizzle and downpours nearly every day, followed by the inevitable floods. It underlined the fact that we live on a damp group of islands and explained why the public think of the UK as having water, water everywhere and always enough to drink.
Yet we only need to go a few weeks without significant rainfall and the reservoirs start to look parched.
And, wherever you live in the world, water sources are under growing pressure. According to UN-endorsed projections, global demand for fresh water will exceed supply by 40 per cent in 2030. The culprits are a combination of climate change, human action and population growth.
The consequences of growing demand and inadequate supply are already with us.
In late 2017, the city of Cape Town in South Africa faced an acute water crisis. Water levels in the dams that supply the city were down to less than 30 per cent of their capacity and people had started to talk about ‘Day Zero’ – the day when water supplies would be switched off and residents would need to queue for their daily ration. Cape Town was in danger of becoming the world’s first major city to run out of water.
The answer was severe water restrictions, cutting consumption in half. By the end of 2018, with further rains, the worst was over.
UK running on empty?
The problem is also hitting closer to home. London may not have the same water issues as Cape Town but there is still no cause for complacency. With an average annual rainfall of about 600mm – less than Paris and only about half that of New York – London draws 80 per cent of its water from rivers. The Greater London Authority recognises that the city is approaching capacity and is likely to have supply problems by 2025 and "serious shortages" by 2040. Hosepipe bans could become more common in the future.
Sir James Bevan, chief executive of the Environment Agency, recently issued a stark warning that unless we do something soon, England is on course for water shortages within 25 years. Rising consumption will meet decreasing supply at a point on the graph known as the ‘jaws of death’ – at that point, we simply will not have enough water to supply our needs.
The warning signs are already there in the form of the Water Exploitation Index (WEI), which identifies whether the rates of water abstraction are sustainable in terms of the amount of rainfall received. WEI is a ratio of mean annual freshwater resources to mean annual total abstractions of freshwater, expressed as a percentage.
Areas with a WEI of above 20 per cent are regarded as over-exploited. According to the Environment Agency, 12 areas in south-east England are already under serious water stress – the same level of water stress as countries such as Italy, Malta and Spain.
The problem can only grow as the climate changes. The latest UK Climate Projections suggest that the UK is likely to experience warmer summers and milder winters, wetter winters and a higher frequency of intense rainfall events, a greater number of severe weather events and more frequent drought and flooding events.
Consumers must do more
We can identify three issues affecting how much water is available for use.
The first is leaks. People often blame water companies if water is lost through leaks yet suppliers are making huge strides in controlling leakage and are committed to further stringent reductions.
Another reason is the quality of treated water returned to the rivers. This needs to be high to ensure minimum processing is required further downstream to make it potable. Since MCERTS was introduced by the Environment Agency 20 years ago, there has been a huge improvement in how utility and industrial companies measure their effluent water discharges.
The third main reason is the real elephant in the room – how much water consumers use and waste and users’ attitude to it.
Part of the problem is that improved housing standards and technological developments have led to increased bathing and washing options, which means increased water use. Add in the pressures of an increasing population and water used in the home accounts for over half of all public water supply use.
Home users see water as an inexhaustible supply and in fact many people resent having to pay for it at all. When water charges were introduced by the Irish government in 2014, there were mass protests at having to pay for what had previously been free. People need to think about whether they really need to wash the car every week, or whether their lawns actually do need so much watering.
For example, the average home uses 140 litres of water a day, 56 litres in the bathroom and 31 litres in the toilets. Nearly half of homes could make efficiency improvements to their toilet, either by using a cistern water displacement device or upgrading to a dual-flush toilet, which would save 12,500 litres per person per year – the equivalent to 150 average-sized baths full.
Water-efficient washing machines and taking showers instead of baths can all help. New water-efficient showerheads can produce water flows that feel far higher than they actually are - an easy way to save both water and energy.
Reduced-capacity baths can also help. A standard bath has a capacity of around 80 litres, so even a half-full bath uses a lot of water. Water-using appliances such as dishwashers or washing machines now carry the new Water Efficient Product Label and/or the Waterwise Recommended Checkmark.
If we could cut household consumption to just 100 litres a day and reduce leaks by 50 per cent, we would have enough water for 20 million people, without taking any more from the environment.
Getting these messages across to consumers requires the efforts of everyone involved in the industry. Many water companies are conducting household water audits and working with social housing providers and schools to educate children on water efficiency. Information on improving household water use is readily available to consumers through water utilities, consumer bodies and DIY chains while some water utilities offer devices for improving efficiency in homes.
The energy factor
Another factor is the energy involved in the business of providing and using water. Many people are concerned about energy production and the carbon dioxide emissions it produces, but water treatment and pumping is an energy-intensive business – for example, Scottish Water is the largest user of electricity in Scotland. A third of all electricity worldwide is used for pumping fluids, and water is bound to make up a large proportion of that. Every litre of water wasted means another litre must be treated and pumped, adding more carbon to the emissions burden.
A lot of water consumers may not even realise that their water use at home contributes to their energy bills, mostly to heat the water – heating water for use in our homes makes up about four percent of the UK’s total carbon dioxide emissions.
Possibly the route to spreading this attitude lies with the young. They have a great awareness of environmental issues but, for many, water use is not currently on their radar. They are more concerned with emissions of greenhouse gases, so linking energy use and water wastage could be the key to getting them on board.
We need a new attitude to water, one that sees it as a strictly limited resource that we guard jealously – as Sir James said, it should be as unacceptable to waste water as it is to blow smoke in a baby’s face or throw your plastic bags in to the sea.
Could the Government do more? Do we need a return to the old public information films from the 70s? With social media behind them, today’s equivalents could go viral and really bring the message home.
Today, many attitudes and practices we never thought twice about in the past are just not acceptable – we need to make wasting water another example of anti-social behaviour.