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centuries, developed indigenous techniques to harvest rainwater. These methods
include Majauba (excavated bund basins for rice production in the lake zone),
Vinyungu (raised broad basins in the Iringa region) and Ndira (water storage struc-
tures in the Kilimanjaro region) (Mbilinyi et al. 2005 ).
In Asia, many communities have emerged and thrived in harsh arid regions
where their social life has evolved around water scarcity and indigenous water har-
vesting techniques. India is one such nation where the ordering of certain social
groups has been arranged around water scarcity. The national annual average rain-
fall in India is 1200 mm, yet regional variations can be as high as 10,000 mm per
year in the northeast and as low as 150 mm per year in the desert regions (Krishiworld
2006 ). In the cool arid region of the Spiti valley, situated in the northern province of
Himachal Pradesh, an intricate system of channels called Kuls has been devised to
harvest meltwater from glaciers. This water is then delivered to local villages in the
valley where the harvested water is used for irrigation purposes, turning this desert-
like valley into one where agriculture is the mainstay (Rainwater Harvesting 2006 ).
Ancient WH techniques are not restricted solely to the old world. In the Americas,
structures left behind by the Mayan civilization indicate a long history of WH. The
Mayans used structures known as Chultuns, an early type of cistern with the capac-
ity to hold 20 to 45 m^3 , to harvest clean drinking water. Furthermore, Aguadas, an
artificially dug rainwater reservoir designed to hold 10 to 150 million liters of water,
and Aquaditas, small artificial reservoirs that could store 100 to 50,000 liters of
water, were commonplace (Gnadlinger 2000 ).
Despite these historical accounts, water harvesting has, within the last few cen-
turies, experienced a decline in implementation and practice due to: the decline of
central powers (e.g. the Byzantine empire in the Middle East) due to political shifts;
warfare including civil war; economic changes, e.g. in competitiveness on local or
export markets; social changes, including availability of cheap labor; aspirations or
attitudes of the people involved in water harvesting; climatic change (increasing
aridity, change in rainfall regime); increasing salinity; decreasing soil fertility; and
soil erosion (Prinz 1996 ; Denison and Wotshela 2012 ; Oweis et al. 2012 ; Lasage
and Verburg 2015 ).
3 The Concept of Water Harvesting
Water is important for life, raising food, social and economic development, and
sustained environmental services. WH can alleviate drought stress in arid and semi-
arid environments and significantly contribute to water livelihood and environmen-
tal management by augmenting domestic water supplies, stabilizing crop yield and
supporting fragile ecosystems. WH has been practiced for centuries in many dry
regions of the world. In arid and semiarid regions, where low and poorly distributed
rainfall makes crop production impossible, WH can make crop production possible.
As such, WH has been employed for thousands of years to irrigate and restore
A. Yazar and A. Ali