Which method is commonly used to manage stormwater runoff in urban areas?

All of the listed methods—retention ponds, detention basins, and green roofs—are effective strategies for managing stormwater runoff in urban areas, making the comprehensive option the most accurate choice.

Retention ponds are designed to hold water and assist in treating stormwater by allowing sedimentation and biological processes to cleanse the water before it is released into the environment. They help reduce flooding and improve water quality by managing the volume and rate of runoff.

Detention basins, on the other hand, temporarily hold stormwater to mitigate peak flow rates. They are typically drained after the rain event has passed, allowing for controlled release of water into downstream systems. This method helps in preventing both flooding and erosion, as well as providing a facility for sedimentation.

Green roofs represent another innovative approach that integrates vegetation into the built environment. They absorb rainwater, reduce runoff, and also provide insulation and habitat for urban wildlife. By capturing and utilizing precipitation, green roofs can significantly reduce the volume of stormwater that would otherwise need to be managed.

Together, these methods form a multifaceted approach to handling urban stormwater challenges, illustrating that effective stormwater management often requires a combination of techniques rather than relying on a single solution.