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Because water harvesting systems increase the amount of water availability to
crops, certain types of plants can survive drought periods and produce greater
yields. With these systems, plant species that can endure periods of intermittently
wet or dry soil will benefit. Plants used in water harvesting systems should have
water requirements which match local rainfall patterns (Renner and Frasier 1995b).
Sorghum and pearl millet are excellent choices for planting in water harvesting
systems; sorghum endures drought and water-logging while millet tolerates drought
but not waterlogging. Maize is inappropriate for water harvesting systems because
it does not tolerate drought or water-logging. Several nut trees, such as pistachio and
almonds, and olives have been used successfully in microcatchment systems
(Tubeileh et al. 2009 ; Yazar et al. 2014 ).
6.2 Economic Design Characteristics
In addition to being technically sound, water harvesting systems must be economi-
cally feasible for the local population. That is, crop or tree production must have
greater benefits than costs (capital and labor). In other situations, WH is economi-
cally beneficial for local farmers because it is the only feasible method of farming
for degraded land which lacks irrigation water. Frequently, the local population will
view WH differently if water is a means of survival as opposed to a method of profit
(Renner and Frasier 1995a; Mekdaschi and Liniger 2013 ).
6.2.1 Labor Requirement
Water harvesting systems are usually labor intensive to construct and maintain.
Depending on the type of WH systems, the capital costs and labor requirements
vary greatly. Some WH systems have high material construction costs and low labor
needs or vice versa (Frasier 1988 ). In some instances, the amount of labor required
to maintain a WH system can be higher than that for construction. Maintenance
labor can be high since the system may need to be inspected and repaired as neces-
sary, especially after major rainfall events (Renner and Frasier 1995a).
6.2.2 Costs Versus Benefits
Proposed WH systems should be closely analyzed to evaluate if the potential costs
versus benefits are economically feasible for the local population. To make a WH
project successful, the system must provide both economic and non-economic ben-
efits. The economic benefits may be monetary profits from the sale of production
items such as crops or trees. Local people may not immediately see the non-
economic benefits of reduced silting in local rivers, soil conservation and aquifer
A. Yazar and A. Ali