LEED AP Building Design and Construction (BD+C) Practice Exam

What percentage of runoff must be managed for the 95th percentile rainfall event?

1. 50%

2. 75%

3. 100%

4. 125%

The correct answer is: 100%

The correct answer reflects the requirement that all runoff from the 95th percentile rainfall event must be managed to reduce the impacts of stormwater on the environment. This event is critical because it represents the rainfall amount that, statistically, is equaled or exceeded 5% of the time. By managing runoff from this level of rainfall, a project can significantly minimize negative effects such as erosion, flooding, and water quality degradation in nearby water bodies. This requirement emphasizes the importance of capturing and managing stormwater on-site through strategies like green roofs, permeable pavements, bioswales, and other low-impact development practices. By effectively managing 100% of the runoff generated by the 95th percentile rainfall event, projects can enhance sustainability, contribute to groundwater recharge, and promote resilience in urban water management. Thus, focusing on full management of this runoff is critical for achieving LEED certification and promoting environmentally responsible design.