Report of the Ground Water Resource Estimation Committee: GEC-2015 (India)

[C. P. Kumar]

Dear Group Member,

Report of the Ground Water Resource Estimation Committee - 1997 (GEC-1997) has been the basis of groundwater assessment in India for last two decades. The latest report of the Ground Water Resource Estimation Committee (GEC-2015) was released in October 2017. Few recommendations of the revised methodology GEC-2015 are given below. 

(1) Aquifer wise groundwater resource assessment to which demarcation of lateral as well as vertical extent and disposition of different aquifers is pre-requisite. 

(2) Groundwater resources may be assessed to a depth of 100 m in hard rock areas and 300 m in soft rock areas till the aquifer geometry is completely established throughout the country through aquifer mapping.

(3) Estimation of replenishable and in-storage groundwater resources for both unconfined and confined aquifers. 

(4) After the assessment is done, a quality flag may be added to the assessment unit for parameters salinity, fluoride and arsenic.

(5) Wherever spring discharge data is available, the same may be assessed as a proxy for ‘groundwater resources’ in hilly areas. 

(6) Refinement in the norms for Specific yield, Rainfall Infiltration factor, Recharge due to Canals, Recharge from Irrigation etc.

(7) Categorisation of Assessment Units Based on Quantity: 

    (Page number 60 - same as GEC-1997) 

Stage of Groundwater Extraction Category

<=70% Safe

>70% and <=90% Semi-Critical

>90% and <=100% Critical

>100% Over Exploited

   (Page number 135 - Minutes of the meeting on 3 December 2015)

Stage of Groundwater Extraction Category

<=65% Safe

>65% and <=85% Semi-Critical

>85% and <=100% Critical

>100% Over Exploited

Report of the Ground Water Resource Estimation Committee (GEC-2015) is available at http://cgwb.gov.in/Documents/GEC2015_Report_Final%2030.10.2017.pdf and also attached to this mail.

C. P. Kumar

Scientist 'G' 

National Institute of Hydrology

Roorkee - 247667 (Uttarakhand)

India