1) Siltation of Bhadra Reservoir
a) In the letter to the Secretary, Irrigation Department by the
Chief Engineer, WRDO (letter No. WRD/MISC/THI) the Chief Engineer and interalia remarked that :-
The Secretary, and AGM
(Administration), M/s. Kudremukh Iron Ore Company Limited, Bangalore in his above cited letters addressed to Government has
stated that M/s. Kudremukh Iron Ore Co. Ltd., has built an earthen dam of 65 M height during 1977-79 across Lakhya river,
which is a tributary to Bhadra river. The purpose of this reservoir is to lead the tailings of Mining operations for avoiding
serious dust pollution. The tailings settle down in the reservoir and the water stored in the reservoir spills over the spillway
provided in the Dam on the right flank and the water flows into the Bhadra river down stream. It is estimated that for every
3 tonnes of crude ore mined 2 tonnes is left into the Lakhya reservoir as waste. It is stated that the existing Lakhya Reservoir
is almost silted up and M/s. Kudremukh Iron Ore Co. Ltd., has proposed to increase the storage capacity of the Lakhya reservoir
by raising the height of existing dam. The Secretary, M/s. Kudremukh Iron Ore Co. Ltd., is requesting approval of Government
for taking up construction of raising the existing dam immediately.
The existing storage is rapidly filling up and may
not extend beyond a further two years of production. Already there is an evidence of tailings being carried over to Bhadra
river. The Chief Engineer observed.
The Secretary, M/s. Kudremukh Iron Ore Co. Ltd., in his letter-dated 16.11.91 has
assured to take up any remedial measures suggested by the Irrigation Department to arrest siltation. In order to prevent silt
getting into Bhadra river, Kudremukh Iron Ore Co. Ltd., may have to explore the possibility of putting up as many smaller
dams as possible in their leased area and recover the silt (Iron Ore) at the end of rainy season as being done in 2 major
b) There after the Chief Engineer, Upper Tunga project had sent his finding to the Engineer-in-Chief on 26th
April 1998 vide CE:VTP2/DLE1:TS2 PB1 - 98-99 which clearly mentions as follows :-
(3) The details of sediment load discharged
into the Bhadra river downstream by the activities of M/s KIOCL may be furnished. In this connection it is to be noted that
during 27th Meeting of Technical Advisory Committee (30) held on 29-3-89, Chief Engineer, Irrigation Central Zone, Munirabad
stated that in view of the works of M/s. KIOCL, Siltation has increased in the Bhadra River below Lakhya dam and the Committee
had decided that the Director, K.E.R.S., Krishnarajasagar should prepare a Technical Report on the increased siltation in
Bhadra Reservoir after mining operations. Further, a comparative study on silt load in Bhadra river below Lakhya dam prior
and after the commencement of mining has, to be made and necessary remedial measures are to be taken up by M/s. KIOCL at their
In reply the KIOCL had stated as follows :-
The very purpose of construction of the tailings Dam is to contain
the tailings discharged from the benefication plant. The overflow from the Spill way during monsoon is monitored jointly with
State Pollution Control Board and it is ensured that the overflow does not carry any silt. This is one of the consent conditions
prescribed by the Pollution Control Board. Further, construction of Dam would result in reduction of siltation in the downstream.
In addition to the construction of tailings Dam, KIOCL has constructed two rock-fill Dams to arrest Mine wash during monsoon.
The arrested Mine wash is being desilted and used in the process for recovery of Iron. As you are aware, whether mining operations
are being carried out by KIOCL or not certain amount of siltation would take place during monsoon. After commencement of
our operation to take care this siltation. KIOCL regularly carrying out desilting of Bhadra river in the Mine Lease Area to
ensure that no siltation is caused to the river at the downstream of Lease boundary.
The Chief Engineer had recommended
to collect the report from Director, K.E.R.S., K.R. Sagar in this matter.
In the same letter the Chief Engineer had remarked
17) The Iron Ore mined contains 38% as useful material and in remaining 62% contains 22% of Iron which will
form the tailings which is required to be stored as the same is allowed to flow in the river will be a major source of pollution.
It is the responsibility of the M/s. KIOCL to store the tailing, in their leased premises and not dump the tailings in the
Government land and river. It is the duty of M/s. KIOCL not to pollute the river and fill M/s. KIOCL have not complied with
the above requirement, resulting in the change of region of the river/tributary. The Chief Engineer observed.
c) In addition
the memorandum submitted by Wildlife First ! has brought in several shocking facts about the siltation levels of Bhadra Reservoir.
Memorandum To Stop Mining By Kudremukh Iron Ore Company Ltd. (KIOCL) Which Is Causing
Serious Damage To The Irrigation
Potential Of Bhadra Reservoir
The 600 sq km Kudremukh National Park forms the largest wildlife reserve
of a wet evergreen type of forest in the Western Ghats. The region receives an average annual rainfall of 7,000mm. It has
been scientifically established that the high elevation grasslands of the Western Ghats are natural climatic climax grassland
formation from stable carbon isotopic analysis, discarding the earlier notion that grasslands are wastelands. The role of
grasslands in these high rainfall areas is of absorbing and moderating the flow of rainfall and preventing soil erosion from
the steep hills of Kudremukh. The rainwater that percolates is gradually released into the streams throughout the year.
Value: The wet climate and the tremendous water retention capacity of the grasslands and shola forest of Kudremukh has led
to the formation of thousands of perennial streams in the region converging to form 3 major rivers of the region - Tunga,
Bhadra and Nethravathi, which forms an important lifeline for the states of Karnataka and Andhra Pradesh by providing sustenance
and livelihood to millions of people living downstream.
Tunga, Bhadra and Nethravathi rivers are mainly tapped at
Bhadra Reservoir with a capacity of 1785.15 M Cums irrigates 1,05,570 Ha of agricultural land in the state of Karnataka, it
has an irrigation potential of 72,700 lakh rupees (Rs.727 crores per year).
Ø TungaBhadra reservoir with a capacity of
3718.34 M Cums (131.312 TMC) which irrigates 6,63,261 Ha of agricultural land (3,75,080 Ha in the State of Karnataka and 2,88,181Ha
in the State of Andhra Pradesh).
Ø River Nethravathi forms one of the important sources of water for Dakshina Kannada
District especially the Port town, Mangalore. A new project by the State Government to tap the water of River Nethravathi
is on the anvil, to divert the water of the river Nethravathi over the Western Ghats to irrigate the Districts of Hassan,
CATCHMENT AREA OF BHADRA RESERVOIR (Annexure-1)
The mining operation of KIOCL is located at the highest
elevation in the catchment area of Bhadra Reservoir at 950m amsl at Kudremukh or the originating point of river Bhadra, while
the elevation of the riverbed level at the Dam site is at 601m amsl. Any damage to the catchment area of river Bhadra at higher
elevation affects everything located downstream of the polluting or the damaging zone.
A report by the STAC sub-committee
for Bhadra Project (Annexure-2) cites the recorded the silt load in river Bhadra just downstream of mining (Malleshwara gauging
site) to be as high as 27,000 metric tonnes per month in the monsoon. Based on this data, the report recommended for a study
on the reduction of the storage capacity of the Bhadra Reservoir due to mining, as the mining operation was not anticipated
during the planning of the reservoir.
SEDIMENTATION OF BHADRA RESERVOIR
Bhadra Reservoir Project was designed for
an overall lifespan of 180 years, which means the potential of Bhadra Reservoir would end by the year 2144 under normal circumstances.
The design of the Reservoir did not take into account the mining operation in the catchment area as it was not anticipated
during the construction of the Dam at Lakkavalli. The Left Bank canal was placed very low, only 11meters above the original
river bed level. The designed lifespan of the Reservoir would have reduced considerably due to heavy soil erosion of the loose
strata in the monsoon from the Kudremukh open cast mining area.
A study on the reduction in storage capacity of Bhadra
Reservoir was conducted by the Karnataka Engineering Research Station, Krishnarajasagara and Regional Remote Sensing Service
Centre, Bangalore in 1998 (Annexure: 3).
This study concluded that the overall reduction in capacity between levels 650.05m
to 657.76m is worked out to be 1.29% in the time span of about 30 years between 1964 and 1992/94 and it works out to an average
of 0.043% per year
It is highly intriguing to note that the Superintending Engineer, in a letter dated 20/9/2000 to the
Chief Engineer (Annexure: 4), Karnataka Irrigation Department, Upper Tunga Project, has interpreted the above report as reduction
in capacity of the entire Reservoir by 0.043 in a span of 30 years. This is highly misleading and amounts to grave misinterpretation
Whether this shocking lapse is due to the reservoir authorities deliberate attempt to cover up the actual damage
or the State Governments direct interference to accommodate the destructive mining of Kudremukh Iron Ore company is a matter
that warrants a high level probe by experts.
It is also stated in the report that the lower levels of the reservoir are
expected to have higher silt deposits. Ironically, only 7-meters at the topmost level out of the total reservoir depth of
57meters (from 650m to 657.75m) was monitored for sedimentation. Nothing was mentioned of the reduction in capacity in the
lowest levels from 601m (the original riverbed level) to 650m.