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Overview of Aquifer Mapping Pilot Programme
Dr S.SureshCentral Ground Water Board
Aquifer Mapping
• A scientific process involving integrated approach• Hydrogeology• Geology• Geophysics• Drilling• Hydrology• Geochemistry
• To characterize the aquifer in terms of • Quantity• Quality
• For Sustainable Management of Aquifer
Need
• Increase in the dependency on groundwater for
meeting the demand of water
• Paradigm shift from groundwater development
to Sustainable Aquifer management
• Aquifer mapping on a larger scale is a
prerequisite for aquifer management at the local
level involving all stake holders.
CGWB Initiatives
• Pilot study taken up under Hydrology project II
• To ascertain the efficacy of various techniques in vogue for
standardization of protocols for aquifer mapping.
• in Rajasthan, Maharashtra, Karnataka, Tamil Nadu & Bihar
covering different hydrogeological terrains
• NGRI has been engaged as consultant
• to ascertain the usefulness & efficacy of various
geophysical techniques for different hydrogeological
terrains
• Make protocol for use of geophysical techniques in
aquifer mapping
Pilot Project Areas
Pilot Project Areas Km2
Baswa-Bandikui Watershed, Dausa District, Rajasthan - I – AQRAJ
598
Maner-Khagaul Area, Patna Dist, Bihar (Watershed GNDK013) - II – AQBHR
521
Watershed WGKKC-2, Nagpur district, Maharashtra - III – AQMAH
360
Parts of Tumkur District, Karnataka- IV – AQKAR
376
Lower Vellar, Cuddalore district, Tamil Nadu - V – AQTND
344
Part of Thar Desert, Jaisalmer District, Rajasthan. - VI – AQDRT
675
Criteria for selection - Pilot Project Areas
Baswa-Bandikui Watershed, Dausa District, Rajasthan (I-AQRAJ)
General Hydrogeological Conditions and Aquifers
Criteria for selection
Thin sand and gravel
aquifers in 80-90 m thick
alluvial cover of the
underlying hard rocks
The area represents hard rocks covered
by alluvium. The area suffers from
fluoride, iron, nitrate contaminations,
salinity and overexploitation The stage
of groundwater development (SGWD) is
173%.
Criteria for selection - Pilot Project Areas
Maner-Khagaul Area, Patna District, Bihar (II-AQBHR)
General Hydrogeological Conditions and Aquifers
Criteria for selection
Aquifers in the thick
(~ 750 m) alluvium of
middle Ganga basin
The area represents thick pile of
Ganga alluvium. The western part of
the area is affected by arsenic
contamination in the top phreatic
aquifers within 50m depth. The SGWD
is 52.5%.
Criteria for selection - Pilot Project Areas
Chandrabagha Watershed, Nagpur, Maharashtra (III-AQMAH)
General Hydrogeological Conditions and Aquifers
Criteria for selection
Aquifers in weathered and
vesicular basalts and
underlying Gondwana
sandstones occurring at
150 to 200 m depth
The area represents Deccan basaltic
Traps underlain by Gondwana sediments.
The area forms part of Nagpur(rural),
Kamaleswar and Seonar blocks, SGWD >
80% (GSDA). Industrial pollution of
groundwater is also reported.
Criteria for selection - Pilot Project Areas
Parts of Tumkur District, Karnataka (IV-AQKAR)
General Hydrogeological Conditions and Aquifers
Criteria for selection
Aquifers in weathered
zone and fractures
underlying the weathered
zone
The area represents the Archaean
crystallines. It forms parts of Tiptur and
ChikanayakanHalli blocks. It represents
semi-critical, critical and overexploited
area and around 2800 wells are dried up.
Fluoride contamination is prevalent. The
SGWD is 158%
Criteria for selection - Pilot Project Areas
Lower Vellar, Cuddalore District, Tamil Nadu (V-AQTND)
General Hydrogeological Conditions and Aquifers
Criteria for selection
Fresh water aquifers in
coastal environment in
semi-consolidated
Cuddalore sandstones
and the overlying alluvium
The area represents alluvium underlain by
thick coastal sediments of Tertiary and
Cretaceous age resting over the
crystalline basement. The area falls in
semi-critical category and is affected by
coastal salinity. The SGWD is 71%.
Criteria for selection - Pilot Project Areas
Parts of Thar Desert, Jaisalmir District, Rajasthan (VI-AQDRT)
General Hydrogeological Conditions and Aquifers
Criteria for selection
The aquifers are mainly
sedimentary rocks of calcareous-
argillaceous-arenaceous nature
of Tertiary and Mesozoic era.
Aquifers are encountered at the
depths of 45 to 70 m and 125 to
160 m. These are unconfined to
semi-confined in nature
Desert Terrain with meager data To
ascertain efficacy of Heliborne survey
for rapid assessment
Objectives• To define the aquifer geometry, type of aquifers, ground
water regime behaviors, hydraulic characteristics and geochemistry of Multi-layered aquifer systems on 1:50,000
• Intervention of new geophysical techniques and establishing the utility, efficacy and suitability of these techniques in different hydrogeological setup.
• Finalizing the approach and methodology on which
National Aquifer mapping programme of the entire country can be implemented.
• The experiences gained can be utilized to upscale the activities to prepare micro level aquifer mapping.
Approach
Activities • Compilation of Existing Data• Preparation of Thematic layers• Identification of Data gap• Data generation to Fill Data gap
• Hydrogeology• Exploratory Drilling• Geophysics• Hydrology• Hydrochemistry
• Data Integration – existing & generated• Aquifer Map Refinement• Groundwater Modeling• Formulation of Sustainable Management Plan
Activities- Data Generation• Hydrogeology• Well Draft study• Water Level Monitoring • Aquifer parameter Estimation • Identification of Recharge Area & Discharge area
• Exploratory Drilling• Well Construction to get sub surface information• Pumping Tests to get aquifer Parameters
• Geophysics• 1 D Geophysics – VES, TEM• 2D Geophysics- Imaging• Heliborne surveys
• Hydrology• Surface water potential• Drainage Characteristics
• Hydrochemistry• Sampling• Delineation of poor quality/vulnerable areas
Outcome Envisaged• New protocols, approach and methodology for National Aquifer
mapping programme
• Micro level aquifer maps for the identified study area will further be used for ground water resource management and planning purpose.
• Integration of existing data and data generated from specific studies into an easily accessible data base in GIS format.
• Comprehensive understanding of the geometry of the aquifer, hydraulic and geochemical characteristics of the aquifer system on larger scale (1:50,000).
• Aquifer Management Plan
Outputs Envisaged• Aquifer wise management plan will provide
• Feasible areas for ground water development along with yield potential / Depth of drilling / safe yields etc.
• Feasible areas for rainwater harvesting and artificial recharge of groundwater vis a vis subsurface space storage available for recharge and surplus non committed surface water available for recharge.
• Aquifer wise vulnerability map indicating ground water stress areas in terms of water availability and quality.
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