1. What Is Constant Depression Head?

Constant Depression Head in a well refers to the steady-state drawdown or lowering of the water level when the discharge from the well is constant. It is a key parameter in hydrogeology for assessing well performance and aquifer characteristics.

2. How Does The Calculator Work?

The calculator uses the formula:

Where:

• \( H \) — Constant depression head (m)
• \( Q \) — Discharge rate (m³/s)
• \( A_{cs} \) — Cross-sectional area (m²)
• \( K_A \) — Specific capacity (m/s)

Explanation: This formula calculates the constant depression head by dividing the discharge rate by the product of the cross-sectional area and the specific capacity of the well.

3. Importance Of Constant Depression Head Calculation

Details: Calculating constant depression head is essential for well design, determining well efficiency, and understanding aquifer properties. It helps in predicting water level drawdown under various pumping conditions.

4. Using The Calculator

Tips: Enter discharge in m³/s, cross-sectional area in m², and specific capacity in m/s. All values must be positive numbers greater than zero.

5. Frequently Asked Questions (FAQ)

Q1: What is specific capacity in well hydraulics?
A: Specific capacity is a measure of well productivity, defined as the discharge per unit drawdown (Q/s). It indicates how much water a well can produce for a given amount of drawdown.

Q2: How does cross-sectional area affect depression head?
A: Larger cross-sectional areas typically result in smaller depression heads for the same discharge, as the flow is distributed over a larger area.

Q3: What are typical units for these measurements?
A: Discharge is typically measured in m³/s or L/s, cross-sectional area in m², specific capacity in m/s or m²/s, and depression head in meters.

Q4: When is constant depression head assumption valid?
A: This assumption is valid in steady-state conditions when the pumping rate has been constant long enough for water levels to stabilize.

Q5: How does this relate to well efficiency?
A: Constant depression head calculations help determine well efficiency by comparing theoretical drawdown with actual measured drawdown under pumping conditions.