What flow of surface run off can be controlled by building retaining walls?

Retaining walls can effectively control surface runoff by slowing down and redirecting the flow of water, reducing erosion and sediment displacement. They create terraces or leveled areas that help manage water movement, allowing for better absorption and drainage. Additionally, these walls can help prevent flooding in low-lying areas by holding back excess water, directing it to designated drainage systems. This overall management enhances land stability and helps maintain the integrity of surrounding landscapes.