Many people wouldn't consider using a sewer line to irrigate a potato crop a good thing, but it is. The reality is that many farmers in developing nations use wastewater for irrigation. Most of the time wastewater is the only source that these families have for water. An estimated 663 million people don't have access to safe water, and the world is facing severe food shortages. Thus, hunger and famine could reach catastrophic levels if not for the reuse of wastewater in agriculture. Consequently, water treatment and its reuse in urban farming has significant economic benefits globally.
In many developing countries, wastewater may be the only option for irrigation in rural and pre-urban areas. And yet in some places where there is a purified water source for irrigation, some farmers opt to still use wastewater. This is due to it's naturally occurring nutrient content which reduces the need for prohibitively expensive chemical fertilizers. This farming practice is a lifeline for poor people throughout the world in Asia, Africa, and Latin America. Most wastewater farmers are basically sharecroppers, who don't own land but rather rent just enough acreage to generate a below poverty level income. Utilizing wastewater for irrigation is essential for their survival.
Benefits of Using Wastewater for Agriculture
The use of Wastewater in irrigation has many benefits such as preserving water, increasing sustainable agriculture, and promoting environmental quality by eliminating the practice of dumping waste into landfills. Because wastewater contains vital nutrients that help crops grow, it serves as a natural type of fertilizer. Vegetables are nourished by potassium, nitrogen, and phosphorus which are vital nutrients found in wastewater. Clearly, there are economic benefits to using wastewater in irrigation, yet these must be considered with the health impacts as well. Countries with high water purification standards ensure that wastewater is properly treated to prevent contamination of bodies of water. This is not a feasible economic solution for many countries. Therefore, using wastewater for agricultural purposes is a better ecological and economic alternative to dumping waste into lakes and streams. In some instances, farmers irrigate crops by pumping wastewater on to acres of land from lakes and nearby ponds. In other cases, the wastewater flows directly onto the crops from open sewer lines. However, the method for distribution will typically depend on the dynamics and resources of the farming community.
Safe Use of Wastewater for Agriculture
Concern for the environment and the health of human beings is always the paramount concern when growing food for consumption. The International Water Management Institute believes that the benefits of wastewater irrigation supersede the negative variables. Utilizing wastewater is essential for the survival of many people in poor countries.
Yet, there are specific things that can be done to make this process safer. It's essential to create cost-effective ways to monitor the presence of harmful components in wastewater. It's also important to create farming practices that reduce the possibility of contamination. Educating populations in poverty-stricken countries could greatly decrease the dangers faced by the part of the world that depends on wastewater farming for survival.
The World Health Organization has stated that one intestinal worm ovum per liter of water is acceptable for agricultural purposes. But these researchers have found up to 150 ova per liter in untreated wastewater. Simplistic water treatment methods such as pond-setting are utilized in countries like Vietnam and have been effective in eliminating most eggs. This process involves creating a man-made pond of wastewater and letting it sit until the feces and worm eggs sink to the bottom. Running wastewater through composite lines is another cost-effective water safety method. During the dry season, implementing bucket drip kits have helped to remove up to six log units of fecal coliforms on vegetables. However, this method is less effective during the wet season. Another health safety solution is for farmers to only use wastewater to irrigate crops such as rice or grains that will be cooked by the consumer. Researchers are now looking into developing even more cost-effective wastewater purification practices that will minimize the risk of infecting farmers and consumers.
Case Study in Wastewater Irrigation
Many Mediterranean countries face frequent droughts. Consequently, these agricultural communities deal with the ongoing issue of water shortages that negatively impacts farming. An agricultural research study took place for a year and a half in Southern Italy on the efficacy of utilizing wastewater in farming. The study analyzed the effects of irrigation with argo-industrial treated wastewater for tomato and broccoli irrigation. Argo-industrial is the method of combining agricultural and Industrial processes in the production of food and fertilizers in developed and undeveloped countries
In this study, the drip irrigation system was used and found to be effective in reducing fecal coliform counts. It was determined that using the agro-industrial techniques ensured that the chemical properties of wastewater met Italian irrigation reuse standards. The results showed that the bounty and quality of the crop were not negatively affected by the wastewater.
The International Water Management Institute and other humanitarian organizations have been working with developing countries to minimize the risk of using wastewater for farming. They have been specifically focused on creating affordable ways to locate hazardous contaminants such as hard metals that surface in crops and soil. They are also attempting to reduce the risk of adverse health-related issues in the general population.
Wastewater economies support the less fortunate around the world. For most of these countries, using traditional western purification methods isn't cost effective or even an option. It is clear that utilizing wastewater for irrigation in agriculture is a sound economic and ecological alternative. Wastewater is only a waste if we choose to squander it. It's application in irrigation holds powerful possibilities for the future of farming in developing nations and quite potentially the future of agriculture as a whole.