1. What is the Fall of Level Calculation?

The Fall of Level calculation determines the vertical drop from the critical point to the mouth of a drain based on the length of overland flow and inlet time. This is important in hydrological engineering and drainage system design.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( H \) — Fall of Level (m)
• \( L_{ob} \) — Length of Overland Flow (m)
• \( T_i \) — Inlet Time (s)

Explanation: The formula calculates the vertical drop based on the cubic relationship with overland flow length and the inverse relationship with inlet time raised to a specific power.

3. Importance of Fall of Level Calculation

Details: Accurate fall of level calculation is crucial for proper drainage system design, ensuring efficient water flow and preventing flooding or water accumulation issues.

4. Using the Calculator

Tips: Enter length of overland flow in meters and inlet time in seconds. All values must be valid positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is Length of Overland Flow?
A: Length of Overland Flow is the distance water travels over the ground surface before it becomes concentrated into stream channels.

Q2: What is Inlet Time?
A: Inlet Time is the time taken by water to flow overland from the most remote point in the drainage area to the inlet of the drainage system.

Q3: What units should be used for input values?
A: Length of Overland Flow should be in meters (m) and Inlet Time should be in seconds (s).

Q4: What are typical values for these parameters?
A: Values vary depending on terrain, but typical overland flow lengths range from 10-1000m, and inlet times range from 1-30 minutes (60-1800 seconds).

Q5: How accurate is this calculation?
A: The calculation provides a theoretical estimate. Actual field conditions may vary due to factors like surface roughness, slope, and rainfall intensity.