Wastewater is a heavily underutilized resource, with over 80% of the world’s wastewater being unmanaged. The challenges with wastewater management is the balance of infrastructure costs and unrealised financial, social and environmental benefits. In many cases, the infrastructure design must also address two principal sources: sanitary sewers and stormwater. The wastewater treatment plants (WWTP), in both cases, are subjected to air emissions, residual effluent, bio-solids, and energy consumption, which may differ in proportions based on the physical and social geographies. Each of these components should be further evaluated at a regional level to manage local impacts and determine their relative importance to their stakeholders (Roeleveld, Klapwijk, Eggels, Rulkens, & van Starkenburg, 1997). Additionally, a national balance is also required to hold nations accountable on a global scale.
The environmental sustainability of a WWTP may be evaluated using a Life-Cycle Analysis and monitoring daily fluctuations of COD, TSS, NH4+ and PO3/4. Muga and Mihelcic (2008) suggest that sophisticated facilities may accrue higher than designed emissions, effluents and residual bio-solids due to the operators’ misunderstanding of the optimal process, especially in rural facilities. These situations can be minimized through the diversion of wastewaters for reuse. Fortunately, the traditional WWTP design and feeder systems allow for water reduction at the source, as a result of water efficient toilets and general water usage awareness (Penn, Schütze, & Friedler, 2013). While water conservation measures are in the spotlight, I believe the expression of social and financial sustainability benefits with regards to wastewater management will stimulate action and improve management of pollutants in used water.
The economic sustainability of wastewater is driven by different factors. Tourism economies are dependent on water availability in order to meet the needs of the tourists. These micro-economies lead the charge in on-site greywater reuse using tertiary filtration systems (Lazarova, Sturny, & Tong Sang, 2012). This essential solution to water deprived tourism economies has led to the development of other economic benefits with wastewater reuse, such as alternatives to energy intensive water treatment and desalinisation processes. Similarly, stormwater management solutions, such as Sydney’s Stormwater Quality Improvement & Reuse Treatment Scheme (SQIRTS), are demonstrating the potential reuse of stormwater for vegetation irrigation within the city, reducing fresh water dependency by 90% (Dallmer, 2002). There is also the environmental and social benefit of reducing uncontrolled pollution runoff from urban areas. Similarly, the Saudi Arabia case integrates energy savings from diversion of desalinisation, where the reuse of wastewater can be used for urban applications, reducing fresh water consumption by 26% and saving $105MM annually as well as 1.75 billion kg CO2 (Kajenthira, Siddiqi, & Anadon, 2012).
Adopting an international vision on wastewater management will drive further research and development of reuse strategies, treatment technologies and infrastructure designs. Not only does wastewater reuse reduce the dependency on fresh water and the associated treatment, it may also become an energy neutral industry. Emerging technologies, such as the Osmotic Microbial Fuel Cell, are reaching beyond the tertiary treatment systems available today by increasing water extraction by over 70% as well as recovering bioenergy that is capable of satisfying the system’s energy requirements (Ge, Ping, Xiao, & He, 2013). Overall, the global impacts of wastewater are being felt and a shared vision is a way of focussing future research and developments, as much on a regional scale as on a global scale. Points of importance include urban stormwater reuse, on-site greywater reuse, and sanitary sewer energy neutrality. These all contribute to maximizing the global implementation and can be applicable to multiple economies.
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A shared international vision can fix the world's attention on the urgency of tackling this challenge. It can help to raise the issue on political agendas, and possibly also help to channel financing. However, buy-in from country leaders and action at the grassroot level is essential to bring about lasting change.
Supranational entities would be a good start to show the importance and the urgency of wastewater management. These supranational entities should create the necessary treaties and have the member states ratify and implement them. Developed countries could provide assistance to developing countries. Punitive measures should be made as a safety net for those countries who will not follow.
What i think is how do these supranatural entities get sovereign governments to implement actions set out in treaties? How would the nature of punishment be to those who would fail to implement the requirements as agreed upon ratification of treaties and still get them to commit themselves? The biggest role of supranatural entities remains to be awareness raising and support of good practice. We should remain hopeful that local activists, academicians and civil societies become strong enough to present facts and convince politicians, policy makers and the general public to engage in activities of wastewater management and prevention of pollution.As one of the members of the live Q&A discussion on wastewater use that it should not appear that National governments are under unecessary pressure, rather we should find a way for this pressure to be felt spontaneously within national governments and cause them to act in favour of wastewater management and pollution control. This can only be achieved if significant information about risks and rewards of wastewater management and pollution control become visible and accessible to all.
Highly developed countries should lead the unified effort in unifying the entire world in order to stimulate action to improve management of used water pollution. By doing so, everyone will be well aware of the importance of worldwide awareness of this very serious problem.
Although the world statistics on wastewater management and pollution do not rule out that the situation is better in developed countries, the situation is obviously worse in developing countries. Experience shows that a community or individuals with less problems tend to be less concerned and i think they have a situational right to behave so, unless there are clear benefits for them to engage in helping a community or individuals with more problems. It is just a nature. So how do you get the people of the world to work together to solve a problem which is unevenly distributed?
The only uniting factor remains that although the wastewater management and pollution activities take place at LOCAL LEVEL, the impacts are felt GLOBALLY. There are many arguments to this statement that have dismantled global initiative to combat climate change and global warming. The truth remains that LOCAL GOALS, TARGETS AND INDICATORS remain to be supperior that GLOBAL VISIONS, TARGETS, GOALS and INDICATORS. It appears to me GLOBAL calls for action dilutes efforts for action locally and sometimes leads to misuse of resources, which would otherwise bring some change locally and reduce the impacts globally.
A shared international vision will stimulate action to reduce pollution in water because of the attention it will bring to the subject. I want to emphasize that the best way for reduction of wastewater to become a reality is if the process if economical/affordable. Today, the costs are too high. What we need are scientists and inventors to keep thinking, researching and developing cost-effective solutions to the problem. It is only when there is a critical mass of entrepreneurs and companies trying to innovate in this area that we can see this happen. Look at the celphone. It used to be big, bulky and very expensive. Today, it is affordable, small and can do an infinite number of functions. Look at the computer, it used to be big, bulky and very expensive. Today, it is affordable, compact and can do an infinite number of functions. If we can make the issue "hip and cool" many companies will jump on the bandwagon and then we can solve this problem worldwide.
A shared international vision allows us to be aware that our concerns are also heard across the globe. When different countries unite for a purpose, such as waste water awareness and action, we generate more strength to pursue our visions. One of the visions we can strive for is that we will fight for the safety of our drinking water by ensuring that we control well our waste water treatment. This will benefit the next generations because they can continue this legacy of cleanliness. The next generations and even the younger generations will emulate our example because we do what is right. An example would be the "no plastic trend" nowadays. Many companies are embracing this trend because companies desire to contribute to the improvement of our lives. In a similar manner, when we create a healthy trend towards managing waste water and our governments pass laws that promote good environment welfare, our actions will naturally follow. We want to contribute to a greater good and the desire increases when we have friends across the globe doing the same. When the benefits are shared online and internationally, the good habit continues. Great results come from good habits.
How can we move towards a global vision, committment, etc on wastewater management? I think part of this is understanding the links between sectors and how smart planning and investment can produce shared benefits. For example, if wastewater is promoted as a resource which can be used for energy and nutrients, then the energy and agricultural sectors recognize the benefits of improved management. This in turn promotes the understanding and need to invest in developing technology and infrastructure which can optimize the extraction of resources.
Para mover algo es necesario que todos empujamos en la misma dirección. Por lo tanto si a nivel internacional tenemos una visión parecida, habrá mas debates y se propondrán mayor número de soluciones. Una vez haya una visión a nivel global, es mas fácil que todos los actores implicados empujen hacia una nueva via de solución del problema.
There is a need for global interest for a global committment to form a global movement toward a global vision. It is need to be shared among water activists, water thinkers, and water professionals, both in society and government. The emerging of the global vision of wastwater management will drive a new spirit to a locally-global action.