Groundwater Resources Potential in Hard Rock Terrain: A Multivariate Approach

Area of Science:

• Hydrogeology
• Geostatistics
• Water Resource Management

Background:

• Groundwater resources in crystalline bedrock are challenging to assess due to complex fracture systems.
• Municipalities often lack resources for traditional hydrogeological assessments.

Purpose of the Study:

• To develop and test a new methodology for assessing groundwater resources potential (GRP) using readily available data.
• To provide a cost-effective tool for sustainable water resource planning.

Main Methods:

• Utilized geological and topographical factors with Principal Component Analysis (PCA) and Analysis of Variance (ANOVA).
• Integrated methods within a Geographic Information Systems (GIS) environment.
• Employed statistical analysis to validate GRP scores against hydrogeological indicators like specific capacity (SC) and transmissivity.

Main Results:

• ANOVA confirmed statistically significant differences in GRP scores across variable groups and hydrogeological indicators.
• PCA results informed the weighting of variables in prediction maps.
• The GRP methodology successfully identified 79% of wells with below-median specific capacity in a verification dataset.
• Statistically significant correlations were found between GRP values and hydrogeological indicators using parametric and non-parametric methods.

Conclusions:

• The developed methodology offers a statistically and hydrogeologically sound approach for assessing groundwater resources potential in heterogeneous crystalline terrains.
• This GIS-based method, using accessible data, provides a valuable alternative to expensive aquifer tests for municipal and regional planning.
• The approach effectively aids in identifying areas with potential groundwater resources, promoting sustainable water management.