1. What is Drainage Slope Calculation?

Drainage slope calculation determines the percentage grade or incline of a surface, which is crucial for proper water drainage in construction, landscaping, and civil engineering projects.

2. How Does the Calculator Work?

The calculator uses the drainage slope formula:

Where:

• \( Drop \) — Vertical drop measurement (in consistent units)
• \( Length \) — Horizontal length measurement (in consistent units)

Explanation: The formula calculates the slope as a percentage by dividing the vertical drop by the horizontal length and multiplying by 100.

3. Importance of Drainage Slope

Details: Proper drainage slope is essential for preventing water accumulation, foundation damage, erosion, and ensuring effective water management in construction projects.

4. Using the Calculator

Tips: Enter both drop and length values in the same units (meters, feet, etc.). Both values must be positive numbers greater than zero.

5. Frequently Asked Questions (FAQ)

Q1: What is the minimum slope recommended for drainage?
A: Typically, a minimum slope of 1-2% is recommended for effective drainage, but requirements vary based on application and local building codes.

Q2: Can I use different units for drop and length?
A: No, both measurements must use the same units to get an accurate percentage result.

Q3: How does slope percentage relate to degrees?
A: Slope percentage can be converted to degrees using the formula: degrees = arctan(slope/100). A 100% slope equals 45 degrees.

Q4: What's the difference between slope ratio and slope percentage?
A: Slope ratio is expressed as drop:length (e.g., 1:50), while slope percentage is the ratio multiplied by 100.

Q5: When is a slope too steep for drainage?
A: Extremely steep slopes (above 25-30%) can cause erosion and may require special drainage solutions or terracing.