Current sectoral water use
Like most of the Gulf Cooperation Council countries, Bahrain has experienced accelerated development growth since the early 1970s as a direct result of the sudden increase in its oil revenues. This has led to a fast increase in its economic base and an improvement in the standard of living, resulting in a rapid rise in the population. The population growth and associated development processes, represented by rapid urbanization, expansion of irrigated agriculture [1] and industrialization in the last four decades, have also brought about substantial increases in water demand. Total water demand has increased dramatically from about 160 MCM in 1970 to more than 432 MCM in 2017 (Figure 1). Despite this increase and the limits of its relatively fresh groundwater resources, Bahrain has done well in providing water for its expanding municipal sector by investing in desalination technology since the mid-1970s. Furthermore, reuse of treated municipal wastewater, particularly for agriculture and landscaping, has been an increasingly important part of the water supply since the late 1990s.
Figure 1: Trends in total water demand, 1950-2017.
Projected water use
Al-Zubari et al. conducted a study in 2018 to assess the impacts of climate change on the municipal water management system (i.e. vulnerability), and to identify appropriate management responses that would lower the system’s vulnerability to these impacts (i.e. adaptation).[2] The study involved dynamic simulation modelling of the water management system and tested various water efficiency scenarios for the period 2013-2030. In its reference scenario, i.e. business as usual with climate change impacts manifested in increasing temperatures and thus increasing municipal water demand, the total estimated municipal water consumption is anticipated to rise from about 310 MCM to about 355 MCM by 2030.
Agricultural water use and irrigation development
Figure 2 illustrates agricultural water consumption for the period 1979-2010. The sharp drop in agricultural water consumption (starting from 1998) is attributed to the widespread salinization of groundwater and the abandonment of agricultural lands as well as the transfer of agricultural lands to urban areas. It is worth mentioning that the area of historical agricultural lands (1965) decreased from about 6,460 hectares (ha)[3] to about 3,400 ha in 2017.
Until 1985, the agricultural sector relied exclusively on groundwater to meet its water needs. However, after the commencement of the project to reuse treated wastewater, it started to rely increasingly on this water, which now covers about 40% of the sector’s water requirements.
Figure 2: Consumption by the agricultural sector of groundwater and treated wastewater for the period 1979-2015, in MCM. Data Source: Ministry of Works, Municipalities Affairs and Urban Planning, 2017.
At present, Bahrain is expanding the reuse of treated wastewater in irrigation, with the primary objective of protecting groundwater from further deterioration in quantity and quality and fulfilling the demands of the agricultural sector as well as the municipality’s water demands for landscaping and beautification. This policy is being implemented by encouraging farmers to use treated wastewater instead of groundwater. The free delivery of treated wastewater to farmers’ lands represents a major component of this strategy, whereby treated wastewater is being was delivered to 547 farms with a total area of about 3,100 ha from the start of the project in 1987-88 until the end of the project in 2017. In the second phase, it is expected that a total of 720 farms with a total area of 4,000 ha will be served by tertiary treated wastewater.
Irrigation methods
In general, water consumption rates in the agricultural sector are considered excessive for many reasons, the most important of these being the predominant use of traditional irrigation methods. In 2016, flood irrigation was used on 65% of the agricultural lands, whereas modern irrigation methods, notably drip irrigation and sprinkler irrigation, were used on 32% and 3% of the agricultural areas respectively (Figure 3). Traditional methods lead to high water losses, resulting in low irrigation efficiency, ranging between 25% and 40%.
Figure 3: Irrigation methods used in Bahrain, 2016.
Crop types
The main crop types cultivated in Bahrain are fodder, vegetables and fruits (including dates). The total cultivated area of these three crops increased from about 2,900 ha in 1985 to about 3,530 ha in 2015. There has been a general increase in the total agricultural production output from about 47,900 tons in 2000 to about 59,100 tons in 2015. Furthermore, the production of fodder crops has been relatively stable, vegetable production has increased and fruit and date production has decreased.
In the last two decades, there has been an increasing move towards the cultivation of alfalfa for fodder. Alfalfa tolerates high salinity, has strong local demand and can be grown all year round. A 2003 study of fodder crops in Bahrain indicated that although alfalfa represented about 25% of the total cultivated area, water consumption by this area represented about 70% of the total water consumption of the agricultural sector, with high water application rates reaching up to 75,000 m3/ha/yr.[4] This high irrigation requirement has a negative impact on agricultural water demand and on groundwater resources.
Average productivity for fodder, vegetables and fruits and dates in 2007 was 36.7, 28.5 and 6.3 ton/ha respectively, which is considered low compared to agricultural systems in other countries. This is due to several constraints facing agricultural production in Bahrain, predominantly limited arable land and low fertility; low water-holding capacity of the soil; harsh climatic conditions; inefficient drainage due to the largely low-lying land; and high salinity of the irrigation water (>2,500 mg/L).
In an attempt to achieve high yields per unit area and per unit applied water, especially in vegetables, many farmers have adopted protected agriculture (greenhouses) with different growing systems like hydroponics and vertical systems, which save water and maximize production in limited space, the two main constraints facing agricultural production. Table 1 illustrates the observed trends in irrigation techniques and agricultural systems for vegetable production for the period 2005-2015, which shows increasing use of protected agriculture and hydroponic systems and decreasing use of flood irrigation. If continued, such trends will undoubtedly save large amounts of water.
Table 1: Trends in irrigation techniques and agricultural systems for vegetable production for the period 2005-2015, in ha.
Agricultural/irrigation system | 2005 | 2010 | 2015 |
Traditional irrigation (flood irrigation) | 456 | 303 | 227 |
Drip irrigation | 177 | 209 | 237 |
Protected agriculture | 48 | 52 | 75 |
Hydroponic system | 0 | 2 | 15 |
[1] Expansion of agriculture reached its peak in the mid-1990s but has since declined due to both deterioration of the quality of groundwater and agricultural land transfer to urban areas.
[2] Al-Zubari W et al., 2018. Impacts of climate change on the municipal water management system in the Kingdom of Bahrain: Vulnerability assessment and adaptation options. Climate Risk Management 20: 95-110.
[3] Al-Zubari W, 1999. Impacts of groundwater overexploitation on desertification of soils in Bahrain – A case study. In: Proceedings of the International Conference on Regional Aquifer Systems in Arid Zones: Managing Non-renewable Resources, Tripoli, Libya, 20-24 November 1999.
[4] Al-Durazi K, 2003. Green fodder production in Bahrain: water cost and alternative approaches. MSc thesis, Desert and Arid Zones Sciences Programme, College of Graduate Studies, Arabian Gulf University, 100 p (in Arabic).