From which pool elevation is the minimum distance to a permanent storm water retention pond measured?

• A. Normal pool elevation
• B. Flood pool elevation
• C. Mean water level
• D. High-water mark

Answer: (B)

The minimum distance is measured from the flood pool elevation. This reflects the highest water surface the pond can reach during storms, ensuring setbacks account for the worst-case rise in water. Using the normal pool level would understate potential inundation, and mean water level is just an average without accounting for flood peaks, while the high-water mark varies by event and isn’t the standard reference. So, the flood pool elevation is the appropriate reference for establishing the setback.