How we waste water
Around the world, no less than 10 billion cubic meters of water is consumed each day by human activity. From these 10 billion cubic meters of water, 80% is dumped into the ecosystem without being treated or reused. Due to population growth, urbanization,shifting consumption patterns, climate change, loss of biodiversity, industrialization and economic growth, the quantity and the overall pollution load of wastewater is expected to increase tremendously. The result of this excessive water consumption and pollution has led one quarter of the world population to live in areas that face extremely high-water stress. On top of that,the global freshwater demand is expected to keep on growing by 2% each year, leading to a global water demand that outpaces the sustainable water supply by 35% in 2040.
Level of physical water stress
Source: Report of UN Water | Progress on Level of Water Stress Global baseline for SDG indicator 6.4.2 2018.
How to prevent wastage of water?
Solid rules, strict policies and company penalties have long been considered to be the solution of disproportioned water use and the associated pollution. However, pollution havens have sprouted as a negative side effect of the inconsistency of the above-mentioned measures. These havens are geographical regions with little environmental regulations, where businesses from all over the world place their production facilities to continue their pollutant activities without being fined. Moreover, in areas that do implement the “polluter pays principle”and thus fine companies that dispose pollutant materials in water streams, water pollution fines often do not outweigh the economic profit of produced goods. This diminishes the incentive for companies to reduce their water polluting activities.
As the existing systems will continue to exacerbate the projected gap between available freshwater supply and demand, research shed a different light on the subject; we have to stop looking at wastewater as pure waste and we have to start looking at it as a potentially affordable resource of energy, nutrients, organic materials and other by-products. In other terms; we have to stop taking a linear approach and start making a circular change.
The circular value of wastewater
In the traditional linear model, water becomes successively more polluted as it travels through the system, rendering future use impossible. When taking the circular approach, waste water will no longer be disposed, it will endlessly be reused and recycled in closed loops. In the last few years, researchers became more and more convinced of the opportunities a circular model could bring. Specifically looking at water, more than 400 billion cubic meters of water can be saved every year by keeping the exploited resources in closed loops and in this manner reducing the input of freshwater.
Within a circular water system, three potential loops are present. The first one focuses on the reuse of water in a closed loop system, whereby the usage of wastewater is determined by cascading quality options. First, upstream investments must be made in order to reduce pollution at the source and facilitate reuse. Furthermore, rainwater harvesting, grey water recycling and reused water are potentially interesting sources for industrial and agricultural water usage. In order to optimise these processes, technical tools and new methodologies are key.
The second loop focusses on the valuable materials and by-products that are often found in polluted water streams. Whenever water is recycled, these materials can be extracted and reused for different purposes. A good example is the use of algae biomass to produce bioplastics. However, at the moment the industrial sector is still sceptical to work with recovered materials as alternatives to newly made or freshly mined resources.
Within the third loop, wastewater is a possible source of energy. Wastewater sludge, for example, can be converted to energy by applying different processes, such as pyrolysis, combustion of biosolids, biogas production and gasification. Currently, biogas production is quickly becoming more popular, since it is often used for fuelling public transport. In addition, the production of biosolids, which processes are nutrient rich and can be used as a fertiliser are increasingly receiving more attention.
As the Netherlands is one of the leading nations in water management systems and circularity, multiple technological advancements have been invented as part of the wastewater solutions. Solely focussing on these tools, however, does not suffice in achieving a fully circular system. In order to take the next step a changing consumer perception is necessary. It was Gerben Hieminga, a senior economist at ING, who is specialised in energy markets and sustainability, who argued: “it is not improving the technology, but it is changing the mentality that causes the biggest challenge in the wastewater question: “It is very well possible to make drinking water out of sewage water, which in many cases is purer than the current drinking water. But we’re confronted with the ‘yuck-factor’.” This article aims to be one of the first contributions in overcoming the previously named factor, by explaining the threats of a negative balance of the current ‘water supply bank account’ and the possibilities on how to easily refund the account by reusing the resources that are already present.
Both in the business context and in the private sphere, more attention should be paid to this evolving crucial issue. Even the smallest changes might have a huge impact! Nexio Projects is a company specialised in sustainability consulting and we are happy to assist businesses in their journey towards becoming more circular.
19/08/2019 – Rotterdam