Which of the following best defines a Rain Garden?

• A. A shallow vegetated depression that captures and infiltrates stormwater
• B. A large concrete channel for directing water
• C. A deep, lined pond
• D. A vertical infiltration trench

Answer: (A)

Rain gardens are designed to manage stormwater where it falls by using a shallow, vegetated depression that temporarily holds runoff and allows it to infiltrate into the soil. The plants slow the water, the soil and mulch help filter pollutants, and the overall system promotes groundwater recharge. That combination—a shallow, planted depression that captures and infiltrates stormwater—is exactly what defines a rain garden.

The other options describe structures that don’t fit that purpose: a large concrete channel is built to move water quickly and isn’t vegetated or designed to infiltrate; a deep, lined pond stores water but uses a liner to prevent infiltration; and a vertical infiltration trench operates beneath the surface rather than as a shallow, vegetated depression.