Reviving a Water Heritage: - Rainwater Harvesting

interesting clues regarding popular perception about the TWHS and/or modern piped water
supply and their readiness to pay for either or both of these systems.
Results
Drawing upon available documentation on TWHS and extensive field surveys in the broad
ecological zones of the Thar Desert and Central Highlands, it is obvious that TWHS not only
vary substantially in terms of technology and management, but also their functioning depends
crucially on the local discrete environment. Keeping these local specificities in view the
potential of selected systems in terms of long-term sustainability can be described in brief, as
follows:
Bavdis in Southwestern Madhya Pradesh: These exist in huge numbers. But, mainly due to
their typically small size and limited storage capacity, these are probably not the best options
for meeting community water needs. However, as observed by the hydro geologists and
water engineers, it is possible to deepen existing talavs and dig new ones that, in turn, would
recharge bavdis. In Dhababavdi (Barwani district) the currently functioning two bavdis serve
a limited purpose and, clearly, cannot address the water scarcity problem of the entire village.
Wells in Western Rajasthan: Wells as TWHS in the western parts of Rajasthan have
continued to prove useful even during summer months in the driest geoclimatic region of
India. Unlike bavdis, wells are extensively used by the rural communities and are well
maintained. All the wells visited in this region during the peak summer season, had good
supply of water and the local perception about its quality was positive. An important hydro
geological characteristic of the wells surveyed was that the structures had been linked to
underground perennial streams/channels. Also, these wells had been built with reference to
the surrounding nadis (TWHS by themselves) so as to receive water recharged through them.
Such ingenious selection of location and construction of the structures ensured a steady
supply of water in the wells. These wells hold much potential to be revived and modernized.
One effective approach would be to desilt, deepen and widen the concerned nadis; this will
ensure a substantial increase in availability of water in the wells, which may be stored for a
long period of time. These structures are also viable options in these regions where piped
water system is most likely to fail due to very low groundwater tables.
Talavs in Kutch, Gujarat: Almost all parts of the Kutch region have suffered substantial
groundwater depletion and salinity ingress. High incidence of poor groundwater bearing
formations has resulted in severe water crisis in the region. Talavs certainly remain an
important solution to the water problem in Kutch. In many villages visited, villagers
considered water from local talavs to be of good quality and that water is available in them
during prolonged spells of summer. The structures in the surveyed villages are unique
examples of interconnected talavs, specially designed to prevent drinking water mingling with
water in other talavs meant for washing or bathing purposes. In terms of size and capacity
talavs are of large dimensions. These are in dire need of revival and modernization and can
surely prove valuable in addressing the water shortage problem in Kutch region. Unlike the
saline groundwater, talavs retain potable water and also recharge surrounding aquifers as
also other TWHS like wells.
Water Quality
A commonly held observation disfavouring TWHS as potential sources of potable water
concerns the ‘unprotected’ and ‘unsafe’ nature of the water. This important dimension of
quality of water of TWHS must be taken into consideration in evaluating their potential. Water
samples from the surveyed TWHS were collected for chemical analyses. Of the seven water
samples collected from individual TWHS, in all the cases the water was found suitable for
drinking; the incidence of total dissolved solids (TDS) was within permissible limits.
Bacteriological analyses of the water samples were also carried out in the laboratory following
scientific instructions. These tests, however, indicated to the unsuitability of the water for
drinking purposes due to the presence of very high concentrations of coliform bacteria.
Irrespective of the fact that most villagers use the water of TWHS for drinking, cooking and
other domestic purposes, these scientific tests indicate deficiencies in water quality. In most
cases, as in the surveyed TWHS, quality of water can be upgraded substantially through cost-
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