Newsletter and Technical Publications
of Alternative Technologies for Freshwater Augumentation
Countries in Asia>
Although Nepal has one of the world's largest per capita water
resources, most of the population does not have easy access to safe
drinking water and, at times, there are acute shortages of water for all
economic purposes. Urban settlements are mostly affected by the shortage
of water whereas, in the rural areas, the problem is linked to lack of
accessibility of water. The main sources of water in the country are
rivers and springs in the hilly regions, and shallow and deep groundwaters
in the Terai. Due to the shortage of water from the municipal supplies in
the urban settlements, primarily in the Kathmandu Valley, there is a trend
toward illegal extraction of underground water using shallow and deep
wells, thereby lowering the water table and leading to the possibility of
land subsidence and foreseeable tectonic effects. Associated problems are
the decline in the yield and productivity of wells and the increasing
incremental cost of lifting water from ever-increasing depths. For these
reasons, Nepal has identified freshwater augmentation technologies to
protect both water quantity and water quality to the extent possible.
Alternative technologies include the use of traditional technologies
such as stone spouts and Pokharis, which were the only sources of water in
the Kathmandu Valley in the past. However, there is a need to conserve and
restore the ponds, aquifers, wells and stone spouts which have been
neglected. Conservation and restoration of stone spouts and Pokharis
is related to spring development and protection. Spring protection
technologies are widely used in the central and eastern hills of Nepal.
These are simple and ideal technologies for use where yield of the source
is very low and water is drawn at the source itself. Likewise, rainwater
harvesting has been popular where there are neither springs nor streams
nearby to fulfill the water demand of the community.
Various distribution systems have also been developed in Nepal based
upon traditional technologies. For example, bamboo piped water supply
systems are not very common, but may prove an ideal system for remote
areas where GI and HDPE pipes and fittings are not available and only
bamboo is easily available and cheap. Use is also being made of hydraulic
rams to pump water using the hydraulic power of the water itself, thus
eliminating the need for diesel or electrical power to drive water pumps.
The principle advantages of this system are its simplicity and lack of an
energy cost in the operation of the system. This system is suitable in
places where there is plenty of water, and the area to be supplied is
situated at a lower level than the source area.