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- Land Use Management—how land, both communal and private, is managed and
used can determine the effectiveness of the WH strategy being proposed or
implemented. Effective land management is important as conflicts and disputes
over water rights, and land ownership and use can arise (Oweis and Hachum
2006 ). - Environmental and Ecological Impacts—ecosystems are often fragile and can be
adversely affected if the water table is tampered with. It is important to pay
attention to these factors, understanding where the water flows and how it affects
the surrounding ecology before implementing any kind of WH system. Some
negative impacts that WH can potentially have on the existing environment are
the reduction of valuable cropland that would be occupied by the catchment area.
The catchment often requires a large area and thus occupies valuable crop land
(Qadir et al. 2007 ). However, today the technology exists to allow for WH to
occur on a larger scale, allowing for various commercial uses such as plant nurs-
eries, garden centers, vehicle washing plants, agricultural uses and for use in
washrooms and urinal flushing in public buildings (Rainwater Harvesting 2006 ).
6 Design Characteristics of Microcatchment Water
Harvesting
Microcatchment water harvesting is a viable means of providing food, fiber and
drinking water if the systems are designed to fit the local physical, economic and
social environment. To design a successful microcatchment system, certain physi-
cal, technical and socioeconomic elements must be investigated.
6.1 Physical and Technical Design Characteristics
For a microcatchment water harvesting system (MCWH) to be successful, certain
physical and technical design characteristics must be considered. In any WH sys-
tem, the runoff collected during rain events must fulfill the needs of the crop during
the growing period in dry, hot weather. The catchment area must have a smooth soil
surface with sufficient slope to generate runoff during the precipitation events. The
soils of the infiltration basin must have sufficient depth with a texture suitable for
infiltrating, retaining and storing runoff water. If the physical system is poorly
designed and managed, soil erosion, flooding and insufficient water to meet the
needs of the crops will occur. Frasier ( 1984 ) commented that no universal water
harvesting technique exists because each location has unique conditions that influ-
ence the design of the optimum system. Some important physical and technical
design characteristics for consideration are precipitation, soil type, slope, runoff and
A. Yazar and A. Ali