Thickness Of Aquifer From Impermeable Layer Given Modified Drawdown In Well 1 Calculator

Formula Used:

\[ H_{ui} = \frac{(s_1)^2}{2 \times (s_1 - s_1')} \]

Unconfined Aquifer Thickness (Hui):

Unit Converter ▲

Unit Converter ▼

From:	To:

1. What is the Aquifer Thickness Formula?

The formula calculates unconfined aquifer thickness from drawdown measurements in pumping tests. It provides a method to determine the aquifer thickness at the initial stage before pumping begins.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ H_{ui} = \frac{(s_1)^2}{2 \times (s_1 - s_1')} \]

Where:

\( H_{ui} \) — Unconfined aquifer thickness (m)
\( s_1 \) — Drawdown in well 1 (m)
\( s_1' \) — Modified drawdown 1 (m)

Explanation: The formula calculates aquifer thickness based on the relationship between drawdown measurements in pumping tests, accounting for the modified drawdown value.

3. Importance of Aquifer Thickness Calculation

Details: Accurate aquifer thickness determination is crucial for groundwater resource assessment, well design, and understanding aquifer storage capacity and flow characteristics.

4. Using the Calculator

Tips: Enter drawdown in well 1 and modified drawdown 1 values in meters. Both values must be positive, and drawdown in well 1 must be greater than modified drawdown 1 for valid results.

5. Frequently Asked Questions (FAQ)

Q1: What is unconfined aquifer thickness?
A: Unconfined aquifer thickness refers to the vertical extent of an aquifer where the water table forms the upper boundary, measured from the impermeable layer below to the water table above.

Q2: How are drawdown measurements obtained?
A: Drawdown measurements are typically obtained through pumping tests where water is pumped from a well and water level changes are monitored in observation wells.

Q3: What is modified drawdown?
A: Modified drawdown is an adjusted value of drawdown that accounts for various factors affecting the measurement, often used in specific analytical solutions.

Q4: When is this formula applicable?
A: This formula is applicable for unconfined aquifers during pumping tests where appropriate drawdown measurements are available.

Q5: What are typical aquifer thickness values?
A: Aquifer thickness can vary significantly, from a few meters to hundreds of meters, depending on geological formations and regional hydrogeological conditions.