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General Resource Status<br />

of Project Watersheds<br />

Villagers collect<strong>in</strong>g water from an agricultural well as<br />

a result of failure of domestic wells, Dhone<br />

Ra<strong>in</strong>fall<br />

Although a widely-held view is that average<br />

annual ra<strong>in</strong>fall has decl<strong>in</strong>ed <strong>in</strong> dry areas of<br />

south-western Andhra Pradesh, this view is not<br />

supported by analysis of ra<strong>in</strong>fall records. There is,<br />

however, an <strong>in</strong>dication that there might be small<br />

seasonal shifts and a small <strong>in</strong>crease <strong>in</strong> ra<strong>in</strong>fall<br />

variability.<br />

Groundwater<br />

In both Dhone and Kalyandurg, there has been<br />

a dramatic <strong>in</strong>crease <strong>in</strong> groundwater extraction for<br />

irrigation dur<strong>in</strong>g the last 10 - 15 years. As a result,<br />

groundwater levels have fallen and, <strong>in</strong> Kalyandurg<br />

<strong>in</strong> particular, shallow wells have failed as deep<br />

borewells have been constructed and as extraction<br />

from deeper aquifers has become the norm.<br />

Although the number and density of wells <strong>in</strong><br />

Kalyandurg and Dhone are similar, levels of<br />

groundwater extraction are around 30% higher<br />

<strong>in</strong> Kalyandurg as compared to Dhone. This<br />

difference helps to expla<strong>in</strong> why 30% of the wells<br />

<strong>in</strong> Kalyandurg are completely defunct or fail<br />

rout<strong>in</strong>ely. The figure for well failure <strong>in</strong> Dhone is<br />

around 8%. Well surveys by the district-level<br />

Andhra Pradesh Groundwater Department<br />

showed that the actual number of wells <strong>in</strong> each<br />

mandal is nearly double the official record.<br />

This f<strong>in</strong>d<strong>in</strong>g has major implications for estimates<br />

of the stage of groundwater development that are<br />

based on well statistics (e.g. the GEC-97<br />

Methodology).<br />

Net groundwater extraction for irrigation,<br />

domestic and livestock use for Kalyandurg and<br />

Dhone was estimated at 11.0% and 8.4% of<br />

mean annual ra<strong>in</strong>fall respectively. As the Andhra<br />

Pradesh Groundwater Department’s estimate<br />

of groundwater recharge <strong>in</strong> this area is<br />

approximately 10% of annual ra<strong>in</strong>fall, this<br />

suggests that current levels of extraction <strong>in</strong><br />

Kalyandurg are not susta<strong>in</strong>able. Analysis of<br />

villagewise groundwater extraction showed large<br />

differences between villages <strong>in</strong> both mandals.<br />

These can be attributed <strong>in</strong> part to more favourable<br />

hydro-geological conditions <strong>in</strong> some villages and<br />

<strong>in</strong> part to variations <strong>in</strong> the historical pattern of<br />

development of both ground and surface water<br />

resources. This f<strong>in</strong>d<strong>in</strong>g illustrates the fact that<br />

there is neither equitable access to irrigation<br />

between villages nor between households with<strong>in</strong><br />

villages.<br />

Data from the automatic ground water level<br />

recorder <strong>in</strong>stalled <strong>in</strong> Kalyandurg as part of the<br />

National Hydrology Project do not correlate<br />

well with the f<strong>in</strong>d<strong>in</strong>gs of the Andhra Pradesh<br />

Groundwater Department’s survey <strong>in</strong> this<br />

mandal. This can be expla<strong>in</strong>ed by the fact that<br />

the recorder is sited <strong>in</strong> an area with a relatively<br />

low level of groundwater extraction. Also the<br />

actual location of this recorder (as with many<br />

others) was chosen primarily on the basis of<br />

security. The broader implication is that automatic<br />

water-level recorder <strong>in</strong><strong>format</strong>ion should be used<br />

9

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