Water demand analysis in Kabul city

Water is a vital resource for human life, an ever-increasing demand for which leads to scarcity in various arid and semi-arid cities. Kabul is a city experiencing water shortages due to population growth. Population growth and climate change are the main causes of water scarcity in Kabul.

Keywords: groundwater, water demand, water consumption.

Вода является жизненно важным ресурсом для жизни человека, постоянно растущий спрос на которую приводит к ее нехватке в различных засушливых и полузасушливых городах. Кабул — город, который испытывает нехватку воды из-за роста населения. Рост населения и изменение климата — основная причина нехватки воды в Кабуле.

Ключевые слова: основная вода, потребность в воде, потребление воды.

Increasing water demand has resulted in a lack of water in many urban areas in the aridity and semi-arid regions. Indeed, Water supplies have been severely strained as a result of population development and the expansion of urban and industrialized areas. Kabul is currently experiencing a groundwater deficit, which is the city's primary source of drinkable water. The groundwater level is being dropped (1 m /year) as a result of fast urbanization and population increase, as well as climate influences, which has resulted in numerous wells drying up in recent years since 1998. Therefore, this research focuses on alternate solutions for preserving water resources and achieving water sustainability by implementing water-saving techniques, such as accessing new water sources (rainwater harvesting), and some of the solutions (faucet aerators, low-flow showerheads, and dual flush toilets), as well as gray-water reuse. To analyze the potential of rainwater in Kabul city, long-term precipitation data from 1960–1980 and 2006–2013 from several stations around the city are used. According to the State of Afghanistan City 2015 study, the rooftops of dwellings are estimated to account for 30 % of the overall land area. Moreover, existing household water efficiency is compared to the most efficient available technologies. The study showed an annual average precipitation of 346 mm and a potential precipitation volume of 38.0 million m3 per year that may be harvested from Kabul city's rooftops. Furthermore, the rainwater harvesting could create an average of 29 L/capita/day (LCD) of water for domestic usage, with a maximum of 75 LCD in February, a minimum of 5 LCD in September, and an annual 9593 L/capita/year (LCY). If we manage the maximum months, then it could produce the full domestic usage (38.1 LCD) until July. Furthermore, in terms of demand management, we have performed a case study on Macrorayon’s (1st, 2nd, 3rd, 4th) apartments that if low flow fixtures were utilized, how much water could be saved? The Macrorayon Department estimates the service population of its system at 100,000 people, the volume of consumption calculated to be 12,500 m ³ / day (125 LCD). Results show that after application of low flow fixtures, per capita consumption can be reduced to 57 LCD, 2.08 MCM/Year would be saved; and an additional population of 119,298 people would be covered by water supply. The result of this study is essential for policymakers to adopt current and future water challenges in Kabul city [1].

Kabul is Afghanistan's largest and capital city, as well as the world's fifth fastest expanding city [1]. According to (2017–18) CSO [2] estimated the population of the city around 3,961,487 in 22 districts. Currently, Kabul city is not equipped with an appropriate water distribution system, that is why almost 85 % of households and inhabitants individually connected to water resources through wells or canals [3]. Groundwater is the main source of potable water, and supply services are inadequate compared to the number of households [4]. The groundwater level is being dropped as a result of fast urbanization, population increase, and climate change impacts, as seen by the drying of several wells in recent years since 1982. [5]. Kabul population is continuously growing up, and there is increasing pressure to further exploitation of groundwater for various purposes. This trend will cause further negative consequences on groundwater quality and quantity [5]. The inhabitants of Kabul are under scarcity of water and would face severe shortages for drinking water. There are high chances to increase water demand in the future due to lifestyle changes [2].

To illustrate the point, The Millennium Development Goals (MDG) state that safe and sufficient drinking water is a critical component of long-term development. Due to significant and continual rural-urban migration into the city in search of a «better» living, Afghanistan's capital city has a big and expanding population [3].

Kabul city quaternary layer groundwater potential estimated 44.5 MCM/Year (MCM: million cubic meter million cubic meter) by KFW in 2005, while 28 MCM/Year is usable that is not sustainable for present water demand.

— Estimated that a population of 5 million people using 125 liters per day requires 228,125,000 m3 per year, which is equivalent to 28,000,000 m3 per year.

— The groundwater table around the city area shown a diminishing trend at a mean rate of 3.8m/year, and it indicates a 23m water from the ground depletion from 2006 to 2018.

— High chances of land deterioration around Kabul city due to high groundwater extractions.

— Lack of proper and applicable groundwater policy yet

We came up with two key strategies to address the aforementioned and future concerns of water shortages in Kabul;

— To increase water availability in Kabul city by constructing new dams, which planned by the government (e.g, Shahtoot dam, Gulbahar Dam, Shah wa Aros Dam, Salang Dam), however, they are time consumed [5].

— To decrease pressure on available water resources through short-term water-saving technics

Kabul city water resources

Water availability in Kabul will be the most significant stumbling block to the capital's development. Kabul's present water supply is solely reliant on local groundwater resources. Four major well fields provide water supply to 30 % of households in Kabul city are Logar, Allaudin, Macroryan, and Afshar, which respectively recharged by Logar, Kabul, and Paghman rivers [4]. The estimated potential of Kabul city groundwater is approximately 44.5 million m3 (MCM) per year, according to the KfW water study [5]. In compared to the city's 3.96 million population's minimal per capita water demand of 40 LCD (litter per capita per day) [2]; it requires 57.8 MCM per year to fulfill the demand, while it shows a 23 % deficit exists. Though if the standard demand of 125 LCD (as per AUWSS Supply to Macrorayon, [3]), the Kabul city residents need 173.5 MCM; a (-183.6) MCM of deficits. Groundwater level fluctuations have decreased dramatically between 1960 and 2000 as a result of low-normal precipitation and increasing population in Kabul's metropolitan districts [5].

Table 1

2018–2019 years Sampling groundwater quality in Kabul city

However, with the increasing rate of population in the city, up to 25 % of these water supply wells are reported to be inoperative or dried [4]. To this point, the population is seeking water at a lower depth of the ground, despite a 2011 DACAAR study confirming that very deep aquifers contain as much salty and low-quality water or other pollutants as fuel water at the Neogene layer [5]. Figure 1 shows a rapid decline of groundwater around Kabul city, and with decline of groundwater, the salinity is increasing [3].

Fig. 1. Groundwater table and salinity trend at different parts of Kabul city.

Conclusion

The key to achieving increased extraction from groundwater sources is to improve monitoring of all aquifers currently proposed to supply Kabul. Without monitoring the existing situation, it is impossible to decide whether the general proposals for the full use of this resource are workable. In addition, without significant investment in the drinking water network and, more importantly, wastewater collection and treatment, much of the proposed investment in a storage or other facility would be disrupted. The costly transport schemes from the Panjshir Valley will only be required after significant investments are made in water and sanitation infrastructure in the urban area of Kabul, which will boost demand.

1. City Mayors Statistics 2018 The world’s fastest growing cities and urban areas from 2006 to 2020
2. National Statistics and Information Authority (NSIA) — Afghanistan 2019 Yearbook Afghanistan statistical 2018–19
3. Qureshi A S 2002 Water resources management in Afghanistan: The issues and options (Colombo, Sri Lanka: International Water Management Institute (IWMI))
4. Houben G, Tünnermeier T, Eqrar N and Himmelsbach T 2009 Hydrogeology of the Kabul Basin (Afghanistan), part II: groundwater geochemistry Hydrogeol J 17 935–48
5. Saffi M H 2011 Groundwater natural resources and quality concern in Kabul Basin, Afghanistan Danish Committee for Aid to Afghan Refugees (DACAAR) 100.