But this success has the seeds of potential failure built in. Unlike major
public sector irrigation schemes, most groundwater irrigation is in the
hands of the private, or informal, sector and is largely unregulated. There
is already growing evidence in many countries of overexploitation, and
irreparable environmental damage to aquifers. Shallow wells run dry,
pumping costs increase, wetlands dry out, streams and river flows decline,
and contamination increases, which also threatens drinking water sources.
Thus concerns are growing over the long-term sustainability of this resource
on which many people have come to depend.