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Rispri LabsENGINEERING A CIRCULAR FUTURE

Free tool · Soil and groundwater

Groundwater Assessment Unit Categorisation Calculator

Stage of groundwater extraction (%) = total annual extraction ÷ annual extractable resource × 100. Under CGWB GEC-2015, up to 70% is Safe, 70 to 90% is Semi-critical, 90 to 100% is Critical and above 100% is Over-exploited.

Your inputs

Results update as you type. Example values are filled in.

ham

1 hectare metre (ham) = 10,000 m³.

% of recharge

GEC-2015: 5% where recharge is by water table fluctuation, 10% by rainfall infiltration factor.

ham/year
ham/year
ham/year

How to use this calculator

  1. Enter total annual recharge for the assessment unit.
  2. Set the natural discharge allocation.
  3. Enter annual extraction for irrigation, domestic and industrial use.
  4. Read the stage of extraction and category.

How is stage of groundwater extraction calculated?

Extractable resource = recharge − natural discharge

Stage of extraction (%) = (irrigation + domestic + industrial) ÷ extractable × 100

Stage of extractionCategory
70% or lessSafe
Above 70% to 90%Semi-critical
Above 90% to 100%Critical
Above 100%Over-exploited

Worked example

With total annual groundwater recharge 10,000 ham, natural discharge allocation 5 % of recharge, extraction for irrigation 6,500 ham/year, extraction for domestic use 800 ham/year, extraction for industry 400 ham/year:

Stage of groundwater extraction: 81.1 %

The calculator also gives annual extractable resource 9,500 ham; total annual extraction 7,700 ham; balance for future use 1,800 ham.

Assumptions and limits

  • Simplified: does not compute recharge from rainfall, canals and return flow, or apply water level trend validation.
  • Uses current domestic extraction rather than a projected allocation.

Frequently asked questions

What is the stage of groundwater extraction in India?

Recent CGWB Dynamic Ground Water Resources assessments put the national stage of extraction at about 60%, with Punjab, Haryana, Rajasthan and Delhi well above 100%.

What does over-exploited mean for groundwater?

The unit extracts more groundwater each year than is recharged. Water levels fall over time and new industrial withdrawals face stricter CGWA conditions.

How often are groundwater resources assessed?

CGWB and state groundwater departments now publish the Dynamic Ground Water Resources of India assessment every year.

References

  • Ministry of Jal Shakti, Report of the Ground Water Resource Estimation Committee (GEC-2015)
  • CGWB, Dynamic Ground Water Resources of India (annual)
  • CGWA, Guidelines to regulate and control ground water extraction in India (2020)

Built and maintained by the Rispri Labs engineering team. Last updated .