This was expressed in the United Nations World Water Development Report 2019, 'Leaving no one behind'. It further disclosed that agriculture's share of total water use is therefore likely to fall in comparison with other sectors, but it will remain the largest user overall over the coming decades, in terms of both water withdrawal and water consumption.
"Water use has been increasing worldwide by about 1 percent per year since the 1980s and this steady rise has principally been led by surging demand in developing countries and emerging economies (although per capita water use in the majority of these countries remains far below water use in developed countries, they are merely catching up). This growth is driven by a combination of population growth, socio-economic development and evolving consumption patterns. Agriculture (including irrigation, livestock and aquaculture) is by far the largest water consumer, accounting for 69 percent of annual water withdrawals globally. Industry (including power generation) accounts for 19 percent and households for 12 percent," it added.
According to the report, over 2 billion people live in countries experiencing high water stress, though the global average water stress is only 11 percent, 31 countries experience water stress between 25 percent and 70 percent while 22 countries are above 70 percent and are therefore under serious water stress. Growing water stress indicates substantial use of water resources, with greater impacts on resource sustainability, and a rising potential for conflicts among users.
"Levels of physical water stress are likely to increase as populations and their demands for water grow, and the effects of climate change intensify. Estimates suggest that if the degradation of the natural environment and the unsustainable pressures on global water resources continue, 45 percent of the global Gross Domestic Product (GDP), 52 percent of the world's population and 40 percent of global grain production will be at risk by 2050. Poor and marginalized populations will be disproportionately affected, further exacerbating already rising inequalities," the report observed.
It makes an interesting, but alarming, observation that about 90 percent of all natural disasters are water-related. Over the period 1995-2015, floods accounted for 43 percent of all documented natural disasters, affecting 2.3 billion people, killing 157,000 more and causing US $662 billion in damage. In comparison, droughts accounted for 5 percent of natural disasters, affecting 1.1 billion people, killing 22,000 more, and causing US $100 billion in damage over the same 20-year period. Over the course of one decade, the number of floods rose from an annual average of 127 in 1995 to 171 in 2004. Climate change is expected to increase the frequency and magnitude of extreme weather events.
To improve the water situation, the report suggested the need to improve water resource management, which is particularly critical for areas experiencing chronic or recurring water scarcity (where demand exceeds sustainable supplies, or where supplies are compromised by pollution, land degradation or other phenomena), the need to improve accessibility exists across all types of hydrological regimes, even in places of relative water abundance.
"Barriers to improved accessibility are often social and/or economic in nature. Although both supply and accessibility are critical to ensuring water security for all, water accessibility has historically received less media (and arguably political) attention. Yet, from the perspective of 'leaving no one behind' and realizing the human rights to water supply and sanitation, overcoming the challenges of accessibility can be equally (and in many specific cases even more) critical than that of addressing issues of supply and scarcity," it added.
According to it, from a technical perspective, the potential responses to addressing the lack of drinking water supply services to groups in disadvantaged and marginalized situations can vary significantly from one place to another, depending on local physical conditions and human and institutional capacities, among others.
Indeed, whereas sizeable high-density urban communities provide opportunities for large-scale centralized water, sanitation and hygiene (WASH) infrastructure and facilities though resource-sharing and economies of scale, less costly decentralized supply and sanitation systems have been shown to be successful solutions in smaller urban settlements.
For people in low-density rural areas, where shared facilities can offer a more affordable alternative to household-level services, the objective is to bring these facilities closer to people's homes, while ensuring and maintaining their safety and affordability.
In terms of selecting the most appropriate WASH technology, the basic principle is therefore not one of 'best practice', but rather one of 'best fit', based on current and expected future socio-economic circumstances. And, in order to select the 'best fit', it is essential to involve the different user groups during the initial decision-making process as well as throughout the implementation and operational phases.
"Addressing the challenges faced by the rural poor, especially in relation to managing water in the context of climate change, will require increased investment in water infrastructure, such as water harvesting or irrigation, improving the advisory services for crop and water management, and planning and implementation of drought preparedness plans. These actions, when coupled with better access to social protection, including social security schemes (pensions and insurance) and more targeted social assistance programmes, will improve the economic and productive capacity of poor smallholder farmers and their families," it added.