What are the three major purposes of using riprap?

The selection of the second choice highlights the primary functions of riprap effectively. Riprap is commonly used in civil engineering and environmental management primarily for its erosion control capabilities. First, it protects soil surfaces from erosion by acting as a defense against the forces of moving water, which can destabilize and wash away soil. This is especially critical in areas prone to flooding or heavy rainfall.

Secondly, riprap is effective in slowing down the flow velocity of water, which diminishes the energy of flowing water and decreases the potential for erosion downstream. This reduction in velocity is crucial for preventing the scour of riverbanks or shorelines, making riprap a key element in sustainable water management practices.

Finally, riprap helps to stabilize slopes by providing a robust layer of protection against landslides and soil movement. This stability is essential for maintaining the integrity of roadways, embankments, and other structures that face the threat of slope failure.

In summary, the three major purposes of riprap—protecting soil from erosion, slowing water flow, and stabilizing slopes—are essential for managing both water quality and the physical integrity of landscapes.