The SWM regulation considers water quantity to protect against which two forces?

The correct choice highlights the importance of managing stormwater to address two significant issues: channel erosion and flooding. Proper stormwater management is crucial for maintaining the integrity of waterways and surrounding ecosystems.

Channel erosion occurs when the speed and volume of water flowing through a channel increase, leading to the degradation of stream banks and the overall channel structure. Effective stormwater management practices, such as the implementation of green infrastructure, can help reduce the peak flow of stormwater runoff, thereby minimizing the risk of channel erosion.

Flooding is another major concern that can have devastating impacts on both urban and rural areas. Excessive stormwater runoff can overwhelm drainage systems and natural waterways, leading to surface flooding that can damage property, infrastructure, and habitats. By controlling water quantity through various stormwater management strategies, communities can mitigate flooding risks, ensuring safer living conditions.

These two forces—channel erosion and flooding—are direct results of poor stormwater management and indicate why the regulation emphasizes their protection to ensure the resilience and sustainability of water resources.