What is a common effect of hard engineering solutions to flood management?

Redirection of flood energy downstream is a common effect of hard engineering solutions to flood management because these systems are designed to control and contain water flow within specific channels or pathways. Structures such as levees, flood walls, and dams manipulate the natural flow of water, which can prevent flooding in certain areas. However, this redirection often results in increased flood risks downstream, as the energy and volume of water that would normally spread out across the floodplain are concentrated and pushed further along the river or stream system.

In contrast, the other options do not align with the typical outcomes associated with hard engineering. For example, while hard engineering can temporarily reduce erosion in certain locations by stabilizing banks, it does not address the root causes of erosion and could exacerbate problems elsewhere. Additionally, hard engineering solutions tend to increase impervious surfaces, which can contribute to higher runoff and flooding rather than minimize them. Lastly, these solutions often do not enhance natural habitats; in fact, they can disrupt ecological systems by altering water flow patterns and reducing the natural floodplain's ability to filter water and provide wildlife habitats.