overview of aquifer mapping pilot programme

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%.


Maner-Khagaul Area, Patna District, Bihar (II-AQBHR)



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%.


Chandrabagha Watershed, Nagpur, Maharashtra (III-AQMAH)



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.


Parts of Tumkur District, Karnataka (IV-AQKAR)



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%


Lower Vellar, Cuddalore District, Tamil Nadu (V-AQTND)



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%.


Parts of Thar Desert, Jaisalmir District, Rajasthan (VI-AQDRT)



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.

Thanks

overview of aquifer mapping pilot programme

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