Certified Storm Water Operator Practice Exam

For effective stormwater management, what velocity should runoff be reduced to?

1. Erosive

2. Non-erosive

3. Controllable

4. Minimal

The correct answer is: Non-erosive

In stormwater management, achieving a non-erosive velocity for runoff is crucial for several reasons. Non-erosive velocities are defined as those that minimize soil erosion, allowing for the protection of both land surfaces and water quality. When runoff velocities are kept below the threshold that causes erosion, the risk of sediment transport and subsequent pollution into waterways decreases significantly. This helps to maintain the integrity of natural water bodies and supports aquatic ecosystems. By designing stormwater systems that produce non-erosive flows, practitioners can prevent the degradation of soil, reduce the incidence of water quality issues, and enhance the effectiveness of stormwater infrastructure. Non-erosive conditions also facilitate better infiltration and groundwater recharge as the water soaks into the soil rather than running off at high speeds that can cause destabilization and erosion. Choosing a non-erosive velocity is also aligned with best practices in sustainable land management, as it promotes soil health and reduces the costs associated with remediation and infrastructure repairs that are typically necessitated by erosion damage.