1. What is the Pumping Rate Equation?

The Pumping Rate Equation calculates the rate at which water is pumped from an aquifer based on transmissivity and drawdown measurements. This equation is essential for groundwater resource management and well design.

2. How Does the Calculator Work?

The calculator uses the pumping rate equation:

Where:

• \( q \) — Pumping rate (m³/s)
• \( \tau \) — Transmissivity (m²/s)
• \( \pi \) — Archimedes' constant (≈3.14159)
• \( \Delta s_D \) — Drawdown across log cycle (m)

Explanation: This equation relates the pumping rate to the aquifer's transmissivity and the observed drawdown during pumping tests.

3. Importance of Pumping Rate Calculation

Details: Accurate pumping rate estimation is crucial for sustainable groundwater extraction, well design, aquifer testing, and managing water resources without causing excessive drawdown or aquifer depletion.

4. Using the Calculator

Tips: Enter transmissivity in m²/s and drawdown across log cycle in meters. Both values must be positive numbers for accurate calculation.

5. Frequently Asked Questions (FAQ)

Q1: What is transmissivity in groundwater hydrology?
A: Transmissivity is the rate at which water flows through a unit width of an aquifer under a unit hydraulic gradient, measured in m²/s.

Q2: How is drawdown across log cycle measured?
A: Drawdown across log cycle is determined from time-drawdown graphs by measuring the change in water level over one log cycle of time.

Q3: What are typical pumping rate values?
A: Pumping rates vary significantly based on aquifer characteristics, but typically range from 0.001 to 10 m³/s for most groundwater extraction wells.

Q4: When should this equation be used?
A: This equation is particularly useful for analyzing pumping test data and estimating sustainable extraction rates from aquifers.

Q5: Are there limitations to this equation?
A: The equation assumes ideal aquifer conditions and may need adjustments for complex geological settings or boundary conditions.