Abstract:
Semi-arid region is a region where the rainfall varies from 250 mm to 650 mm per year. Because
of less rainfall , high evapo-transpiration , surface and ground water availability is very less in
these regions. It leads to water scarcity and drought conditions. Conventional water harvesting
structures are not suitable in these regions. Hence there is need to go for alternative solution such
as water harvesting from thin air. The aim of this research work is to find alternative method of
water harvesting from thin air to overcome drinking water problems in semi-arid regions. The
objective of this study is two fold , firstly to carryout comparative analysis of different water
harvesting structures from thin air and secondly to carryout feasibility and cost analysis of Warka
Water Tower in semi-arid region. In this research work , different water harvesting structures
from thin air were studied and Warka Water Tower was found to be most economical and
convenient because of its low initial cost , zero energy requirement and less maintenance cost
and easy availability of construction material. The rate of discharge of a Warka Water Tower is
100 lit per day , however its efficiency can be increased with suitable conditions. Hence Warka
water tower can be effectively used for drinking water purpose in semi-arid regions. In this
study, feasibility analysis of Warka Water Tower was carried out and it was found that the
structure is suitable at temperature 40 degree Celsius and relative humidity 50 -70 %. Cost
analysis shows that the cost of a single Warka tower is 33,000 rupees.
