Riprap

[4][5] Rubble from building and paving demolition is sometimes used,[3][6] as well as specifically designed structures called tetrapods or similar concrete blocks.

[9] Riprap affects the amount of organic material in a waterbody by acting as a filter, catching wood and leaves before they can enter the water.

Introducing ripraps creates a rocky environment that can affect a waterbody's ecology by making the ecosystem more heterogeneous.

[10] While it can negatively affect some organisms by removing shoreline vegetation, the rock can provide important refuge for invertebrates and small fish.

[8][11] By preventing woody plants from growing and shading the water, riprap can also increase the amount of algae and hydrophytes.