Well Volume Calculator

Estimate the standing water volume in a drilled well.

How the Math Works

The Well Volume Calculator uses the formula for the volume of a cylinder: gallons = π(d/2/12)² × depth × 7.48. Here, the diameter (d) is first converted to radius by dividing by 2, then to feet by dividing by 12 (since diameter is often measured in inches). Squaring this radius and multiplying by π gives the cross-sectional area of the well in square feet. Multiplying by the well's depth (in feet) calculates the volume in cubic feet, which is then converted to gallons by multiplying by 7.48 (the number of gallons in a cubic foot). This step-by-step approach ensures accurate water volume estimation for cylindrical wells.

Practical Applications

To apply this calculation, first measure the well's diameter in inches and its depth in feet using a measuring tape or rod. Input these values into the formula or calculator: convert the diameter to radius in feet, square it, multiply by π and depth, then scale by 7.48 to get gallons. This is particularly useful for well owners, farmers, or property managers who need to determine water storage capacity for irrigation, livestock, or household use. The result helps in sizing pumps, planning water usage, or assessing well efficiency during maintenance checks.

Day-to-Day Use

Knowing your well’s water volume is critical for everyday water management. It prevents overuse during dry periods, ensuring a steady supply for drinking, farming, or emergencies. Homeowners can estimate how long their well will last between refills, while farmers can optimize irrigation schedules to conserve water. Additionally, understanding your well’s capacity aids in budgeting for water usage costs or planning for drought resilience, making it a practical tool for sustainable resource management in daily life.

Worked example

6 in, 100 ft deep → ~147 gal.

FAQ