The Sun: An Efficient Solution for Water Sanitation

There is no dubiety about the case of Pakistan’s severe water crisis. Several individuals and organizations have placed themselves in the responsible role to get to grips with this problem. While they have made some headway through the installation of handpumps and the construction of wells, when one comes to learn of the disturbingly high level of arsenic in Pakistan’s groundwater, there is still cause for great concern. It is frustrating to see another problem stem out of an attempt to manage a complication, but there is hope. A recent study regarding the problem of contaminated water in the village of Kaudikasa, India, contended solar energy to be a vital ally in the fight for sanitary water in rural areas.

Arsenic, as defined by MedicalNewsToday, is a semi-metallic, chemical element that naturally prevails in groundwater (Paddock, 2018). It is found in small amounts scattered in the air and earth around us. Some areas may have larger amounts of arsenic, owing to mining, excessive use of pesticides, or simply as the result of natural circumstances. It is exceptionally toxic in its inorganic form. The repercussions of immoderate exposure to arsenic are linked to harrowing maladies, like skin lesions, cancer, and cardiovascular disease. Children pregnable to this may also experience delayed or deficient neurodevelopment. According to the World Health Organisation (WHO), the most substantial risk of exposure to arsenic is through consuming contaminated groundwater – by drinking it, using it to prepare food, or irrigating food crops (Arsenic, 2018). In her article, Niazi (2018) states that The International Agency for Research in Cancer (IARC) “has ranked arsenic a group 1 human carcinogen which causes lung, bladder and urinary cancers.”

Unfortunately, Pakistan is one of the several countries plagued with the threat of arsenic-contaminated water. Bearing in mind that the WHO’s baseline qualifies water containing 10 micrograms/l arsenic as safe for drinking, (Guglielmi, 2017) let’s look at some statistics. 20% of Punjab’s population is exposed to over 10 micrograms/l of arsenic in drinking water, 3% to more than 50 micrograms/l, and 36% of Sindh’s total population is vulnerable to arsenic-contaminated drinking water (Niazi, 2018). Millions in the subcontinent have been at risk of arsenic poisoning since the drilling of wells in Bangladesh and India in the 1970s. Guglielmi (2017) highlights how it is perceived as “the largest mass poisoning in history.” Environmental scientist, Joel Podgorski, conducted a study in Pakistan, measuring the concentration for arsenic in its groundwater; he discovered that virtually two-thirds of the water near the Indus River valley exceeded WHO’s limit. His team then estimated the number of people that depended on groundwater for drinking and concluded that loosely fifty to sixty million people in Pakistan may be consuming water containing more than 50 micrograms/l of arsenic (Guglielmi, 2017).

So, now that we know all this – what next? How should Pakistan, a developing country keeping barely afloat amongst its other copious share of problems, deal with this? The remedy should be effective, cost-efficient, and long-lasting. And what says all those things better than solar energy?

This is in fact the direction that Jasrotia et al. opted for when dissecting the problem of arsenic-contaminated groundwater in the village of Kaudikasa, India. Groundwater used by villagers was found to have up to 6.1 micrograms/l, and around 108 people were suffering from ailments induced by arsenic (Jasrotia et al., 2012, p. 102). Their project, which aimed to sanitize water from dangerous levels of arsenic, utilized solar stills. These instruments are proven to be effective in the process of purifying water. A solar still comprises of two water troughs – one filled with water to be purified, the other empty. The troughs are covered by a glass pane angling downward toward the empty one. The heat from the Sun evaporates the raw water, which touches the glass pane and condenses as pure water, collecting into the empty trough (Sherwood, 2017). These stills can be placed on flat rooftops, or on ground with an underground storage system. A total of 48 samples of raw water, distillate, and brine water were used for quality analysis. While raw water had an average of 6 micrograms/l, the distillate had less than 0.01 micrograms of arsenic per liter, meeting the WHO standard of drinking water. Jasrotia et al. calculated the cost of this system for the village of Kaudikasa, made of 328 households, which came around to be an estimate of USD 20,418. According to them, this estimate is ten times less expensive than the cost of water supply from a distant reservoir, which was being put in the plan by the Public Health Engineering Department (PHED).

In their journal article, Jasrotia et al. (2012) discuss in detail how to manage the brine water left after the contaminated water is purified through the solar still – an algal pond is used to treat brine combined with domestic sewage. The by-products obtained from the process are biomass, which can be utilized for bioethanol production, and the sewage liquid in the algal pond itself can be passed through Activated Alumina, which absorbs arsenic efficiently, leaving behind uncontaminated water that can be used on a communal level for irrigation.

As can be gathered from this study, there are significant benefits in adopting this system of water sanitation to combat the risk of arsenic poisoning in areas where groundwater is the primary source of water, in Pakistan. There is exceptional potential to replicate this process in Pakistan, where sunshine is abundant and inexhaustible – there is extraordinary potential for utilizing solar energy. The use of solar still is an inexpensive way to solve the problem of water contaminated with arsenic in the rural areas of Pakistan, where people are most affected by illnesses sourced in arsenic poisoning. With this procedure comes a minimal cost, no hazardous by-products are produced and provides a system to ensure safe drinking water for members of the community.


Arsenic. (2018, February 15). Retrieved from:

Guglielmi, G. (2017, August 23). Arsenic in drinking water threatens up to 60 million in Pakistan. Retrieved from:

Jasrotia, S., Kansal, A. & Kishore, V.V.N. (2012). Application of solar energy for water supply and sanitation in Arsenic affected rural areas: a study for Kaudikasa village, India. Journal of Cleaner Production 60 (2013) 102-106. DOI: 10.1016/j.jclepro.2012.07.030

Niazi, M. (2018, October). Arsenic in Drinking Water in Pakistan and Associated Health Risks. International Journal of Advanced Research, 6(11). DOI: 10.21474/IJAR01/7970

Paddock, M. (2018, January 4). What is arsenic poisoning? Retrieved from:

Sherwood, C. ((2017, April 24). What Is a Solar Still? Retrieved from:

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