Groundwater worldwide are estimated that they relay on

is found in saturated zones of rock, rock –soil system aquifer which has high
porosity and permeability. Throughout the world groundwater resource is categorised
as the reasonable source of freshwater. Since there are not availability of
total statistics on groundwater use and abstraction. But more than 1.5 billion
people worldwide are estimated that they relay on groundwater as the source of
drinking water (Clarke .te .al 1996).The escalation of human activities leads to
the excessive groundwater demand which ultimately increased input of polluant
(Stauffer et al., 2011). The water which is found in the pores in subsurface is
called groundwater and tie space available in between the rock and sand is
called zone of saturation (Dixit A. and Upadhaya M. 2005). It is estimated that
97% of the freshwater available in earth is groundwater except the water store
in glacier and icecaps (Nace, 1967; Shiklomanov and Rodda; 2003). “Urbanization
extensively change the local hydrology changes in landcover will of then reduce
recharge amount and change recharge distribution” (Tellam et .al, 2006).
According to the availability of groundwater in Kathmandu valley the source is
categorized in three component namely: a) shallow groundwater system, b) deep
groundwater system and c) rock aquifer system where the main source of water
for domestic use is extraceted from shallow aquifer and for the commercial use
water is extracted from deep aquifer (Shrestha et al, 2012).  Groundwater use has been practice in Kathmandu
valley since long ago using dugwell, dhunge dhara, and pump but in modern the
use of resource is done by drilling (Bajmaya S, 2012). From mid 1980s the use
of groundwater in valley is Sharpe inceased because of the demand of the large
poputation, centralization of the population and commercialization of Kathmandu
valley (Binnie and Partners, 1988). The large use of groundwater source which
exceed the recharge along with the unproper management of waste (Solid waste,
sewerage) has decreased the quality of groundwater and make the source
vulnerable (Pandey, 2010). The well which are installed by NWSC in the
deep aquifer for commericial supply of water have shown a drawdown of 15-20m
from the time of construction of well which clearly indicate substantial
overexploitation (Jha et al. 2012). The drawdown in groundwater level is the
indicator of water scarcity.  Today the
Kathmandu valley water sector has biggest concern in management of the adequate
water supply as well as maintain the quality of water (Pathak et al, 2009). The
capital of Nepal Kathmandu valley urbanization indicate as one of the fastest
in South Asia (Muzzini and Apericio, 2013; MOUD, 2015). According to the census
report the population growth rate in Nepal is 1.34 where inside the Kathmandu
valley the growth rate is 4.45 which indicate rapid urbanization of valley.
From the data collected by census the population increased in Kathmandu by
61.2% within last decade (CBS, 2012). The capacity of the aquifer in Kathmandu
valley to storage groundwater is equal to 2.1 BCM (Pandey et al 2010).
Eventhough the Kathmandu valley has the highest potential to store groundwater
because of the formation of the aquifer but because of excessive demand of
water by the increased population has already created the stress because of the
excessive abstraction then the recharge therefore the sustainable use of the
groundwater source has became the first necessary considering future growth in
water demand (Pandey et al 2012).

the water demand is increasing steeply and source is depleting tramendenously
so importance of rainwater to recharge the groundwater basin is priority for
future supply. But during the artificial recharge the presence of colloidal and
suspended partical in rainwater runoff are higher then groundwater so rainwater
which is supposed to harvest should be primarily treated through various
chemical, physical and biological process should be done along in the
filtration path (Peter et al. 1998).  While
developing strategies for artificial rainwater recharge the concern authourity
should primarily identify potential areas for groundwater recharge which will help
protect the areas to improve the quality of natural or artificial groundwater
recharge in Kathmandu valley. (Nakamura et al 2012).

Kathmandu valley is categorized as highly populated urban area so land cover is
changed. Different data shows about 1,755 mm per annum rainfall occurs in
Kathmandu valley which means the good amount of precipitation but due to the
land formation and the urbanization the large portion of water is drained out
though the rivers. (Nakamura et al 2012).  As Kathmandu valley landcover is changes from
agricultural area to urban due to the population expansion which will effect
the recharge by reducing recharge amount along with changes the recharge
distribution (Tellam et al. 2004). Deu to the improper management of sewerage
system cause a sequence of ecological and economic problem, various hazardous
material may be injected to the groundwater due to leakage while in some cases
there might be the chance of sewer system act as drainage of high volume of
groundwater if it is constructed below the groundwater table (Held et al.
2004). Unplanned disposal of municipal wastes leads leaching of pollutant has
evidently causes  deterioration of
shallow groundwater quality reported high level of ammonia, iron and arsenic in
deep groundwater and E. coli and nitrate mainly in shallow aquifer (Chapagain
et al. 2012). The ultimate aim of urban groundwater studies is to develop the
sound theoretical understanding necessary to develop management technique which
will deliever sustainability (Tellam et al. 2004).

the population started to increased the groundwater resource has been a reliable
sourse of water supply in Kathmandu valley from early 1970s till today but
method of extraction has changed from stone spouts, dugwell to modern
mechanized extraction (Shrestha et al. 2012). Due to sharp increase in the
demography, urbanization, and industrialization the demand of groundwater
source is high which leads to the extraction increased by 2.3 MLD  (Binnie and partners, 1988) to 80 MLD in 2011
(Dhakal et al, 2011). To cope with this problem Nepal government implemended
various Act for the rational utilization, conservation, management and
development of the water resources that are available in the territory of Nepal
which are found in the form of surface water, underground water (Water Resourse
Act, 1992). Under the act the power to gives certificate of registration for
the groundwater user in notified area along with the right to investigate,
search, inspect and even seize any mechanical equipment which are utilized for
illegal sinking. (Irrigation Act, 2000). After taking detail description about
the place of extraction, number of benificary and availability of source along
with quantity “District Water Resources Committee” are allowed to gives
liscense for the project (Water Resourse Rule, 1993). Under this all rules the
beneficial use of water is allowed to a person or a corporate body without
causing damage to other. (Water Resourse Act, 1992).

there are different laws and regulation related to water source are under
implementation but groundwater in contex of Nepal has remained an “unregulated
resource”. The motive of this study carried out with the aim of evaluating the
different legal and technical strategies that are implemented by the government
to provide quality and adequate quantity of water to the citizen along with the
conservation of resourse. This study also focus with the shortcoming in the
different strategies made to conserve and utilize the resourse and recommend
some technical and legal provision.