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ASSAM AGRICULTURAL COMPETITIVENESS PROJECT- Additional Financing. Groundwater Monitoring System. Background - rationale for this system.
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ASSAM AGRICULTURAL COMPETITIVENESS PROJECT-Additional Financing Groundwater Monitoring System
Background -rationale for this system • Abundance rainfall during monsoon (ranging from 1500 - 3000 mm), yet farmers are unable to maximize income, as they lack access to water during winter months • World Bank financed ARIASP & AACP provided irrigation pumps for shallow tube wells (STW) to farmer groups, for tapping high watertable & abundant groundwater in Assam • Installation of STW needs to be done considering balance between recharge potential & potential discharge to meet crop demand, water logging mitigation measures, so as to protect existing investment in STWs • Increasing number of installed STWs, therefore warranted monitoring to avoid over exploitation of groundwater for ensuring its sustainable use
NERIWALM study of 2004 …. Key findings NERIWALM: North Eastern Regional Institute of Water and Land Management
NERIWALM study of 2011 …. Key finding The number of STWs to installed per district under AACP and other schemes is determined based on these two Studies done under AACP
Objective of Establishing GWM System • AACP-AF aims to establish a comprehensive groundwater monitoring system to support Agriculture Department in- • Taking strategic decision on future investments on STW programs, water recharge structures, etc • Planning density of STW with respect to hydro-geological regions • Planning agriculture based interventions to manage water demand leading to sustainable use of resources • Water level & quality monitoring stations • Include installation of piezometers, telemetric digital water level recorders (DWLR) and water quality sensors (at selected locations) coupled with stations. • Telemetric system for automatic monitoring at required frequency
VISIT TO HIMACHAL PRADESH & PUNJAB • Team of officials from PCU and Agriculture Engineering Dept. led by SPD had visited HP and Punjab to have first-hand exposure of Groundwater monitoring system established under Bank financed HP-II
VISIT TO HP & Punjab: experience gained • Bore-well locations: based on grid maps • Network of Bore-wells: equipped with DWLRs and telemetry systems • For groundwater data collection & uploading to a central Server system in real time • Measurement Frequency: • Should be adequate to detect short-term & seasonal groundwater fluctuation • Should be able to discriminate effects of short-term and long-term hydrologic stresses • Shallow aquifers frequent measurements, while deep confined aquifers need less. • Measurement Frequency should link to withdrawal of GW
VISIT TO HP & PUNJAB: EXPERIENCE GAINED ..CONTD. • To address manpower constraint in Agriculture Dept. -telemetric system of Piezometer should be installed • Location of Piezometers must be in public places such as Block Office, Govt. owned premises for safety • Piezometer Diameter should be atleast in 6” (150 mm) • Boreholes should be protected with RCC box on top • Adequate protection measure for Piezometer necessary
IMPLEMENTATION ARRANGEMENTS • GW Monitoring Cell established-Nodal Officer in place • Prepared 15x15 Km Grid map of Assam and also for each districts: All except two Hill districts covered (25 districts) • Finalized total number Piezometer based on grid map: 250 • Areas near river basins excluded • Exact location of Piezometer being finalized – would be completed before award of contract for civil work • Collaboration with CGWB for Technical Advice/Support • Time frame: • Complete Civil Work: within 6 months; by Sep. 2013 • Procurement Telemetric DWLR, through ICB: Sep. 2013 • Commissioning of the GW system: Oct. 2013
IMPLEMENTATION ARRANGEMENTS … Contd • Process for hiring experts for GWM Cell such as Hydro-Geologists, Chemists, GIS expert, computer operators, etc. for GWM cell is ongoing- TORs being drafted • Existing district level engineers, would be given additional responsibility to look after GWM stations. Identified engineers would be trained • GWM Cell would also have responsibility of monitoring GW quality, regarding presence of any hazardous elements • Automatic Weather Station (AWS) will also be installed for each block in the State • Telemetric-GSM system would be web enabled, with open data sharing principle, online data back-up arrangement
Groundwater Monitoring Well Design .. Key elements • Diameter of the bore hole-150 mm • Depth of bore-hole-Standard 30 meter • Lockable steel cover to be fitted & secured in concrete box seal, to protect bore-wells • Vent hole near top of protective casing to prevent explosive gas build-up & to allow water levels to respond naturally to barometric pressure changes • Drain hole at base of protective casing to prevent water build-up. • Concrete box seal to extend below frost depth • Bore-holes would be placed at an elevated area to avoid flooding
DISTRICT WISE No. OF PIEZOMETER BORE-HOLE Bid Doc. for Civil Work finalized
Way Ahead • Determine location/ elevation of piezometers accurately using GPS, so that groundwater flow maps can be prepared • Share the GW data to Irrigation Dept., CGWB and other agencies for needful. • Findings of GWM system, could pave the way for adoption of Ground Water Policy for Assam • State has recently adoption Groundwater Act THANKS CLICK