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collecting water from roofs and construction of suitable storage facilities (Pereira
et al. 2002 ). To maintain water quality, rooftop WH systems should have appropri-
ate screens and purification systems built into the infrastructure to remove leaves
and twigs from the water and to purify the water prior to use (O’Hogain et al. 2011 ).
A rooftop WH system installed in 2007 in Tekke village of the Beypazari
Municipalities included some filtering equipment so that the stored water could be
used for drinking and kitchen use.
4.2 Microcatchment Water Harvesting
Microcatchment water harvesting (MCWH) is a method of collecting surface runoff
from a small catchment area and storing it in the root zone of an adjacent infiltration
basin with the plant (Boers and Ben-Asher 1982). Water productivity in water har-
vesting catchments is usually related to that measured in small plots (Frasier 1984 ).
The size of the catchment affects runoff such that, under the same hydrological
conditions, a small area may generate up to 50 % of rainfall as runoff compared with
only 5 % of rainfall runoff from river basins (Stern 1979 ). The higher the runoff
generated per unit area from a small catchment forms the basis of microcatchment
water harvesting as an alternative option (Ali et al. 2010 ).
Common MCWH structures include continuous and intermittent contour ridges,
semi-circular bunds, pitting, natural depressions, inter-row water harvesting, Meskat
types, vellarany types, contour bench terraces, eyebrow terraces or hill slope micro-
catchments, contour strips and negarim basins (Prinz 1996 ; Hatibu and Mahoo
1999 ; Yazar et al. 2014 ). Small earthen or stone-made structures are constructed
across the land slope along the contour. Construction along the contour ensures
smooth water spreading. Land slopes between 2 and 8 % are considered suitable for
MCWH, but these structures have been constructed on flat land and slopes up to
20 %. Rectangular or hexagonal shapes are suitable for this purpose. Frequent dam-
age and high maintenance costs are the main limitations to the development of
MCWH on steep slopes (Prinz 2002 ).
Microcatchments involve a distinct division of a runoff-generating catchment
area (generally less than 1000 m^2 ) and a cultivation basin where runoff is concen-
trated and stored in the root zone and productively used by plants (Hatibu and
Mahoo 1999 ; Oweis and Hachum 2009 ). The distance between the catchment area
and runoff receiving area is usually less than 100 m. There are multiple advantages
to this WH system in that the design is simple and cheap, there is higher runoff
efficiency than the larger-scale WH systems, they often prevent or reduce erosion,
and they can be implemented on almost any slope or level plane (Prinz 1996 ). The
use of MCWH will depend on local conditions and the type of crop that receives the
runoff water.
A. Yazar and A. Ali