1. What is Drawdown in Well 2?

Drawdown in well 2 refers to the peak-to-trough decline in water level during a specific period for the second well in an aquifer system. It represents the difference between the initial water table level and the current water level in the well.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( s_2 \) — Drawdown in well 2 (m)
• \( H_a \) — Width of aquifer measured from impermeable layer to initial water table (m)
• \( h_2 \) — Depth of water in 2nd well (m)

Explanation: The formula calculates the drawdown by subtracting the current water depth in well 2 from the total aquifer thickness measured from the impermeable layer.

3. Importance of Drawdown Calculation

Details: Accurate drawdown calculation is crucial for assessing aquifer performance, determining well efficiency, and managing groundwater resources. It helps in understanding the impact of pumping on the aquifer system and planning sustainable water extraction.

4. Using the Calculator

Tips: Enter the width of aquifer (Hₐ) and depth of water in well 2 (h₂) in meters. Both values must be positive numbers, and the aquifer width should be greater than or equal to the water depth.

5. Frequently Asked Questions (FAQ)

Q1: What is the significance of drawdown measurements?
A: Drawdown measurements help determine aquifer characteristics, well performance, and the sustainable yield of groundwater resources.

Q2: How does drawdown affect well performance?
A: Excessive drawdown can indicate over-pumping, reduced well efficiency, or limited aquifer capacity, potentially leading to well failure or water quality issues.

Q3: What factors influence drawdown in wells?
A: Pumping rate, aquifer properties, well construction, distance from pumping well, and duration of pumping all influence drawdown measurements.

Q4: How is drawdown different from water table decline?
A: Drawdown refers to the temporary lowering of water level during pumping, while water table decline refers to long-term, permanent lowering of the groundwater table.

Q5: When should drawdown measurements be taken?
A: Drawdown measurements should be taken during pumping tests, at regular intervals during operation, and after recovery periods to assess well and aquifer performance.