1. What is Inglis' Formula?

Inglis' Formula is used to estimate runoff depth in inches for ghat areas. It calculates the portion of precipitation that flows over the land surface into streams, rivers, or other water bodies based on rainfall depth.

2. How Does the Calculator Work?

The calculator uses Inglis' Formula:

Where:

• \( RII \) — Runoff Depth in Inches
• \( RPI \) — Rainfall Depth in Inches

Explanation: The formula calculates runoff by multiplying rainfall depth by 0.85 and subtracting 12 inches, providing an estimate of surface water runoff.

3. Importance of Runoff Calculation

Details: Accurate runoff estimation is crucial for water resource management, flood prediction, irrigation planning, and environmental impact assessment in ghat areas.

4. Using the Calculator

Tips: Enter rainfall depth in inches. The value must be valid (greater than 0).

5. Frequently Asked Questions (FAQ)

Q1: What are typical RII values?
A: Runoff depth values vary based on rainfall intensity and duration, but typically range from a few inches to several feet during heavy rainfall events.

Q2: How accurate is Inglis' Formula?
A: The formula provides a reasonable estimate for ghat areas but may need adjustment based on specific local conditions and topography.

Q3: When should this formula be used?
A: Inglis' Formula is particularly useful for hilly or mountainous regions (ghat areas) where topography significantly influences runoff patterns.

Q4: Are there limitations to this formula?
A: The formula may be less accurate for extreme rainfall events, areas with different soil types, or regions with significant vegetation cover.

Q5: Can this be used for urban areas?
A: While the formula can provide estimates, urban areas with impervious surfaces may require different runoff calculation methods.