Groundwater potential describes the likelihood of finding productive aquifer conditions at a location. The application combines aquifer properties and recharge conditions and identifies the areas that justify geophysical surveys and exploratory drilling.
OutputPotential map per category and a combined groundwater potential map
DecisionPrioritisation of areas for groundwater exploration
ScaleWatershed to country
Built forA defined aquifer or aquifer system
Default categories
The suggested criteria fall into two categories: the properties that let an aquifer store and transmit water, and the conditions that replenish it. Direct aquifer evidence is preferred; terrain and land-cover indicators serve as proxies where such evidence is missing. These default categories can be renamed or removed by the user, and new categories can be added.
Aquifer characteristics
Lithology, thickness, hydraulic properties, weathering and fracturing of the aquifer.
Recharge conditions
Water input from rainfall and recharge, and the surface conditions that control infiltration.
The criteria library is maintained continuously. In each project, criteria can be added, removed or renamed.
Potential, yield and sustainability
A potential map indicates where groundwater is likely to occur in usable quantities. It does not establish how much water can be abstracted without depleting the aquifer.
Potential
Relative likelihood of productive aquifer conditions, mapped by the application.
Yield
Productivity of individual wells, determined by drilling and pumping tests.
Sustainable abstraction
Volume that can be withdrawn over time, derived from the water balance of the aquifer.
Constraints
Constraints exclude areas where abstraction is not possible or not permitted, such as protected areas, built-up areas or zones of saline groundwater. The application suggests none.
From criteria to potential
- CriteriaStandardised so that high scores consistently mean high potential; correlated indicators selected, not combined
- Category mapsWeights within each category give its potential map
- Potential mapWeights between the categories combine the category maps
- Target areasContiguous areas of very high potential in which no criterion falls below a minimum value
The direction of each criterion usually follows from its effect on storage and replenishment: high transmissivity, a thick saturated zone, weathered or fractured rock and high recharge increase the potential, while steep slopes and low-permeability cover decrease it. Several criteria express the same effect: hydraulic conductivity, saturated thickness and transmissivity are related, as are rainfall and recharge. Selecting one of each pair avoids counting the same influence twice. Weights come from the analytic hierarchy process, ranking, rating, the multi-influencing factor method or an anonymous stakeholder survey.
Results
The result classes rank the locations within the study area by their relative potential; they do not predict well yields.
Sensitivity analysis shows which areas keep their class when the weights change. Validation against independent well data, such as yields or borehole success rates, will follow in a later version.
Typical questions
- Where should geophysical surveys and exploratory drilling concentrate?
- Which villages lie in areas of low potential and need alternative supply options?
- Which hard-rock areas offer weathered or fractured zones with usable groundwater?
- How does the potential pattern change when proxies replace direct aquifer data?
Case stories
No case stories for this application yet.
References
- Díaz-Alcaide, S., Martínez-Santos, P. (2019). Review: Advances in groundwater potential mapping. Hydrogeology Journal 27(7), 2307–2324. doi:10.1007/s10040-019-02001-3
- Machiwal, D., Jha, M.K., Mal, B.C. (2011). Assessment of groundwater potential in a semi-arid region of India using remote sensing, GIS and MCDM techniques. Water Resources Management 25(5), 1359–1386. doi:10.1007/s11269-010-9749-y
- USGS. Aquifers and groundwater. U.S. Geological Survey, Water Science School. usgs.gov
Start a groundwater potential project
Select “Groundwater potential” when creating a project. The suggested criteria appear in step 2.