A spreadsheet method of estimating best-fit hydraulic gradients using head data from multiple wells

Area of Science:

• Hydrogeology
• Environmental Science
• Geoscience

Background:

• Calculating hydraulic gradients and horizontal flow is crucial for understanding groundwater movement.
• Traditional methods can be time-consuming and require specialized software.

Purpose of the Study:

• To introduce a convenient method for determining hydraulic gradients and horizontal flow regimes.
• To leverage spreadsheet software for efficient hydrogeological data analysis.

Main Methods:

• Utilized spreadsheet matrix-solving functions to determine the water-table plane equation (Ax + By + Cz - D = 0).
• Employed derived coefficients to calculate the magnitude and direction of the hydraulic gradient.
• Developed a downloadable Excel file for processing data from up to 20 wells.

Main Results:

• Successfully determined the equation of the water-table plane from well data.
• Provided formulas for calculating hydraulic gradient magnitude (sqrt(A2 + B2)/C2) and direction (arctan B/A).

Conclusions:

• Spreadsheet software offers a fast and accessible tool for hydrogeological calculations.
• The developed method simplifies the analysis of groundwater flow from extensive well datasets.