Fog Water Collection: Challenges beyond Technology

Abstract

Abstract:The Sustainable Development Goal (SDG) 6, calling for access to safe water and sanitation for all by the year 2030 supports the efforts in water-scarce countries and regions to go beyond conventional resources and tap unconventional water supplies to narrow the water demand-supply gap. Among the unconventional water resources, the potential to collect water from the air, such as fog harvesting, is by far the most under-explored. Fog water collection is a passive, low maintenance, and sustainable option that can supply fresh drinking water to communities where fog events are common. Because of the relatively simple design of fog collection systems, their operation and maintenance are minimal and the associated cost likewise; although, in certain cases, some financially constrained communities would need initial subsidies. Despite technology development and demonstrated benefits, there are certain challenges to fog harvesting, including lack of supportive policies, limited functional local institutions, inexpert communities, gender inequality, and perceived high costs without undertaking comprehensive economic analyses. By addressing such challenges, there is an opportunity to provide potable water in areas where fog intensity and duration are sufficient, and where the competition for clean water is intensifying because water resources are at a far distance or provided by expensive sources.

Water harvesting technologies in semi-arid and arid areas

“…Water harvesting could be explained as all actions to accumulate obtainable water resources, provisionally storing leftover water for consumption when needed, especially in drought seasons or when no continuing water resources are existing (Kalkidan and Tewodros, 2017;Lani et al, 2018). The initial point is to collect natural water resources from fog, rainwater, runoff water, groundwater or even waste water, which if not would have been runaway (Patel and Shah, 2015;Srivastava et al, 2015;Madkour et al, 2018;Qadir et al,2018). Water harvesting is also defined as "The collection and management of floodwater or rainwater runoff to increase water availability for domestic and agricultural use as well as ecosystem sustenance" (Studer and Liniger, 2013).…”

Gender and Community Mainstreaming in Fog Water Collection Systems

“…Water-scarce countries and communities need a new water paradigm considering a range of unconventional water resources to narrow the water demand-supply gap [6]. Such water resources are critically important to address local water shortages [7,8]. One such resource is water embedded in fog, which is particularly valuable in dry areas where fog events are common.…”

“…From there, water flows into a storage tank that local community members can access and draw from when needed [9][10][11]. Post-installation, fog water collection systems require little physical and monetary upkeep, making them an attractive, though unusual, water source [7].…”

“…One unit of the SFC has an area of 1 m × 1 m (1 m 2 ), while the size of LFC varies from 40 m 2 (4 m × 10 m) to 48 m 2 (4 m × 12 m) per unit. The number, size, and type of fog collectors to be installed in a specific location depends on the fog characteristics, such as fog thickness, duration and frequency of occurrence, as well as the climate and topography of the area, water demand, and financial and human capacity of the associated community to run and maintain the fog collection system [7]. Fog days range from 60 to 360 days on fog collection sites, while daily fog water yield varies from 2 to 20 L m −2 of fog water collection unit.…”

“…Extensive reviews are available on the history, characteristics, and technical features of fog water collection [14][15][16] as well as on policy and institutional aspects, economic and financial dimensions, and capacity-building activities [7,9]. However, information on trade-offs of community and gender aspects of fog water collection is scattered and fragmented, warranting a review to combine existing knowledge of community and gender aspects of fog water projects across the globe.…”