Download full report in pdf format - Natural Resources Institute

Groundwater quality
The current WHO permissible limit for the
fluoride concentration of drinking water supplies is
1.5 ppm with the added recommendation that
“climatic conditions, volume of water consumed
and intake from other sources should be considered
when setting national standards”.
In 1993, the Bureau of Indian Standards set a
maximum permissible fluoride concentration of
1.0 ppm, although concentrations of up to
1.5 ppm are considered to be acceptable in the
absence of an alternative safer source.
Figure 27 shows the number of wells that were
sampled in Dhone that have fluoride
concentrations in excess of 1.5 ppm. It can be seen
that 468 of the wells sampled had fluoride
levels in excess of 1.5 ppm. Of these, 62 were
being used solely as a source of domestic supply.
Preliminary water sample analysis for Kalyandurg
suggested a relatively lower prevalence of wells
with fluoride in excess of 1.5 ppm as compared
to Dhone. However, follow-up analysis by
the WHiRL Project, indicated that high fluoride in
domestic water supplies is a major issue in
Kalyandurg. The routine monitoring of wells by
the WHiRL Project also indicated a widespread
increase in fluoride concentrations of around
30% during the 2002/2003 drought. Although
a reasonable level of awareness exists at the village
and district levels of the risks to human health
related to high levels of fluoride ingestion,
Figure 27. Sampled wells in Dhone with fluoride
exceeding domestic water permissible limits
a laxness was noted in the way in which fluoride
permissible limits are being used by departments
responsible for drinking water supplies. A
consequence being that action is not taken even
when fluoride levels are well in excess of Indian
permissible limits (i.e. 1.5 ppm).
Although not such a severe problem as fluoride,
the common occurrence of saline groundwater in
both mandals was found to be a problem in some
domestic supplies and, in some areas, a major
constraint on agricultural use. In Dhone, fifty of the
sources of domestic supply were found to exceed the
permissible limit for total dissolved solids.
Conclusion
The overall conclusion of the “groundwater”
component of the Audit is that the scope for
developing additional groundwater resources
in both mandals is limited and, in much of
Kalyandurg, groundwater is already severely overexploited.
This conclusion does not agree with a
recent statewide groundwater survey carried out by
the Andhra Pradesh Groundwater Department. This
difference of opinion can be explained by the fact
that the statewide survey based estimates of
groundwater draft on “official” figures for irrigated
area and well numbers that appear to hugely
underestimate the situation on the ground.
48