Lessons learned: Traditional rainwater harvesting systems deserve renewed attention
image: Indigenous water harvesting methods.
Credit: Musaed Aklan
For thousands of years, communities in drylands developed practical systems, indigenous rainwater harvesting systems, to capture, store and distribute scarce water. These approaches include rooftop rainwater harvesting, floodwater diversion, runoff farming, terraces, cisterns, ponds, tanks, springs and qanats (underground channels that carry groundwater by gravity from aquifers to settlements or fields).
A review published in International Soil and Water Conservation Research shows that these systems played a central role in sustaining communities across generations. They supported drinking water supplies, irrigation, livestock, flood protection and settlement in places such as Yemen, Iraq, Iran, Syria, India, Tunisia, Morocco, Oman and the Mediterranean region. Some remain in use today.
However, the authors found that indigenous rainwater harvesting systems are declining in many regions. "The main drivers include groundwater pumping, rural-to-urban migration, climate change, changing water policies, weak institutional support, modern infrastructure development, loss of collective maintenance systems and natural disasters such as floods and earthquakes," shares lead author Musaed Aklan from Sana'a University in Yemen.
Notably, groundwater abstraction is one of the most important causes. In several countries, traditional systems such as qanats have been replaced by deep wells and motorized pumps. "While these technologies can provide easier access to water in the short term, they can also lower groundwater tables, dry up traditional systems and increase long-term vulnerability," says Aklan.
The authors found that the decline of traditional water systems has also contributed to the loss of local knowledge. "Many indigenous systems depend on collective maintenance, skilled labor and community rules for sharing water," Aklan explains. "As young people leave rural areas and maintenance practices disappear, the physical structures degrade and the knowledge needed to operate them is lost."
Ther authors noted that revived indigenous systems can produce three broad benefits. First, they can provide water for domestic use, agriculture and livestock. Second, they can improve hydrological conditions by increasing groundwater recharge, reducing runoff, limiting erosion and helping control floods. Third, they can preserve local heritage and traditional knowledge.
The authors cautioned, however, that revitalization should not mean simply copying the past. "Indigenous systems need to be adapted to current social, environmental and economic realities," says Aklan. "By combining traditional knowledge with modern technologies, such as machinery, improved engineering design, mapping tools, drip irrigation, remote sensing and better institutional support, can make water harvesting more resilient and productive."
###
Contact the author:
Musaed Aklan
Sana'a Center For Strategic Studies, Sana'a, Yemen
Water and Environment Center (WEC), Sana'a University, Yemen
The publisher KeAi was established by Elsevier and China Science Publishing & Media Ltd to unfold quality research globally. In 2013, our focus shifted to open access publishing. We now proudly publish more than 200 world-class, open access, English language journals, spanning all scientific disciplines. Many of these are titles we publish in partnership with prestigious societies and academic institutions, such as the National Natural Science Foundation of China (NSFC).