What is the significance of the berm in cup trench construction?

• A. A high berm on the outermost downhill side helps to catch rolling material and prevent it from crossing the handline.
• B. A berm marks the start of the line.
• C. A berm is used primarily to store equipment.
• D. A berm is purely decorative.

Answer: (A)

In cup trench construction, preventing material from rolling down onto the handline is a key safety and effectiveness goal. Building a high berm on the outermost downhill side creates a physical barrier that catches soil, rocks, and embers that might slide or roll toward the line. This keeps the handline intact and reduces the risk of material crossing the line or starting a new fire crawl across the trench.

The other ideas don’t fit because the berm isn’t used to mark where the line starts, store equipment, or serve decorative purposes. Its purpose is strictly to contain and control loose material on slope, preserving line integrity.