Conserving Water Resources and Protecting the Planet
Water scarcity is a growing concern worldwide, and it can have severe impacts. In regions with severe drought or water scarcity, there is a risk of "Day Zero," when the demand for water surpasses the available supply, and cities or regions are forced to shut off water to households and businesses. The consequences of such a situation can be dire. Various industries would come to a standstill, and agriculture, which consumes over 70% of the world's freshwater, would be impossible without water. This would lead to food shortages, higher prices, and potentially famine in some areas. Additionally, lack of clean water can lead to the spread of waterborne diseases, which can be fatal and further exacerbate the situation.
Therefore, it is crucial to manage water resources efficiently and effectively to prevent water scarcity and ensure that communities have access to clean and safe water. Effective water and wastewater management can help mitigate the impacts of water scarcity, protect public health and the environment, and support sustainable development. Those who work with wastewater treatment see wastewater as a resource that can augment water demand.
This Earth Day, we reflect on the importance of water and wastewater management in our society's sustainability efforts. Clean water is essential to human health and well-being, and wastewater management is a critical part of ensuring that water is clean and safe for use. Without proper treatment, wastewater can contain harmful pollutants that can harm aquatic ecosystems, wildlife, and public health. By managing wastewater effectively, we can protect the environment and public health, conserve water resources, and recover valuable resources.
Effective wastewater management involves several steps, including treatment, disposal, and reuse.
Wastewater treatment removes pollutants and contaminants from wastewater to produce treated effluent that can be safely discharged into the environment. The treatment process involves several stages, including primary treatment, secondary treatment, and tertiary treatment.
- Primary treatment involves removing large solids and debris from wastewater using screens and settling tanks.
- Secondary treatment involves biological processes that use microorganisms to break down organic matter in wastewater.
- Tertiary treatment involves advanced treatment technologies, such as membrane bioreactors, that can produce high-quality effluent that can be reused for various purposes, including irrigation, industrial processes, and even potable water.
Wastewater treatment can also recover valuable resources, such as nutrients and energy. Anaerobic digestion is a process that can convert organic matter in wastewater into biogas, which can be used as a renewable energy source. Nutrient removal is a process that can recover nutrients, such as nitrogen and phosphorus, from wastewater and convert them into fertilizer for agricultural use.
Wastewater disposal is another critical aspect of wastewater management. Proper disposal of wastewater ensures that it does not contaminate surface water or groundwater. Land application and ocean discharge for treated wastewater that meet specification, and deep well injection for certain raw wastewater are some of the methods of wastewater disposal, each with its own advantages and disadvantages. The choice of disposal method depends on several factors, including federal, state, and local regulations, availability of land, and environmental considerations.
Water reuse is an emerging aspect of wastewater management that can help conserve water resources and address water scarcity. Reclaimed water can be used for non-potable purposes, such as irrigation, industrial processes, and toilet flushing. In some cases, reclaimed water can be treated to potable standards and used as a source of drinking water. Water reuse can reduce the demand for potable water, protect water resources, and provide a reliable source of water for non-potable uses.
The United Nations reports that more than 2 billion people lack access to safe drinking water, and this number is expected to rise due to population growth, urbanization, and climate change. Effective wastewater management can help address water scarcity by providing a reliable source of non-potable water for various uses. Globally, the world produces an estimated 360 billion cubic meters per year of wastewater and only re-uses 11 percent of it. In water scarce region like Middle East and North Africa, the re-use rate is 28 percent of wastewater produced. And in North America, the re-use rate is 12 percent.
As we celebrate Earth Day and recognize the importance of water and wastewater management, it is essential to understand the critical role that these systems play in sustaining our planet. Effective wastewater management not only protects public health and the environment, but it also has the potential to mitigate climate change. Through practices such as water reuse and resource recovery, wastewater can become a valuable resource in our efforts to reduce greenhouse gas emissions.