Rapid urbanization, the major cause for sand demand is responsible for unsustainable extraction of sand from dried
river paths. The layers of sand deposits are exploited almost up to the bottom. This in turn, has increased initial and
premature failure of irrigation wells in riparian areas. This study is a modest attempt to estimate the negative
externalities due to sand mining along Uttara Pinakini river in Gauribidanur, Karnataka, India using field data from
Sand mining area (SMA) and Non-sand mining area (NSMA). In SMA (NSMA) proportion of well failure is 0.46
(0.3), groundwater extracted per well 20.67 (32.12) acre inches, negative externality per well Rs. 4189 (Rs. 1328),
net return per rupee of groundwater Rs.4.32 (Rs.11.88). In SMA (NSMA), as location of well from sand mining area
increased from 30 to 1500 feet negative externality per well reduced from Rs.7080 to Rs.1585 (Rs.1394 to 1462). In
Bangalore city, price of sand was Rs. 4200 per truckload of 350 cubic feet; with inelastic demand (η = - 0.88) and
transporters earn net return of Rs. 835 per load. It is suggested to impose a Pigouvian tax of Rs. 540 on each sand
truck load in order to compensate the farmers for loss incurred due to sand mining at the rate of Rs. 4813 per
irrigation well.
Details
Title
EFFECT OF SAND MINING ON GROUNDWATER DEPLETION IN KARNATAKA
Record Identifier
https://ageconsearch.umn.edu/record/43619
PURL Identifier
http://purl.umn.edu/43619
Page Range
1 - 15
Total Pages
15
Note
Groundwater is a crucial source of irrigation for the farmers in Gauribidanur taluk to eke out the living since there is
no other perennial source of irrigation. Currently the irrigation wells in the riparian areas of uttara Pinakini River are
seriously threatened due to excessive sand extraction, which in turn affects the groundwater recharge. This has
manifested in increase in proportion of well failure. It is imperative that sand mining is seriously (negative
externality) affecting the interests of the economy of riparian farmers in this river basin. This calls for a serious,
effective and efficient implementation of regulation of sand mining for the benefit of both agriculture and civil
works.
Currently sand extraction is permitted up to three feet by remitting a royalty of Rs.45 per truckload of sand to the
Department of Mines and Geology. On the other hand, however, sand miners are excavating even up to 40 feet in
Uttara pinakini stream. Thus, department of mines and geology has to seriously monitor the sand mining activity for
the overall benefit of society.
The estimated negative externality per irrigation well in the Gauribidanur SMA was Rs. 4186 per year. There are
about 8000 irrigation wells located in the riparian areas of the Gauribidanur river stream, where sand mining is
actively being undertaken. Thus, the total estimated negative externality is Rs.3,34,88,000. The total estimated sand
accumulated in uttara pinakini river stream is 1,74,00,000 cubic meter in fifteen years, of which 61 percent was
extracted, constituting 1,06,14,000 cubic meter or 37,14,90,000 cft in fifteen years(6). Therefore annual sand
extracted is 2,47,66,000 cft imposing externality of Rs 1.35 per cft or Rs .540 per load. In order to conserve the sand
resources, along the riparian areas, this environmental cost Rs 540 per load should be imposed to internalise the
pressure on this natural resource in the market price of sand. Imposition of the pigouvian tax of Rs. 540 per truck
load of sand transported will create a corpus fund with the Government’s Department of Mines and Geology with
which (i) the farmers possessing irrigation wells which have failed due to sand mining would be compensated on the
basis of loss in net returns which would result from mining a truck load of sand.
Series Statement
PRESENTATION AT THE V INTERNATIONAL R & D CONFERENCE OF THE
CENTRAL BOARD OF IRRIGATION AND POWER, 15-18 FEB 2005, BANGALORE