Photo Credit: Karl Jansen
Revetments, riprap, large rocks… they all mean the same thing in this case. These rocks placed along the side of a river are formally known as revetments. Their purpose is to absorb energy from the water rushing by. By absorbing the passing water’s energy, they do their job to prevent erosion of the river bank. Riprap is usually the term used for rocks placed where runoff from a large storm might cause environmental impact problems like erosion.
Photo Credit: Jessie Benaglio
Pictured above is a landslide. Landslides occur when the stability of a slope changes from a stable to an unstable condition. Some natural causes for a landslide are groundwater pressure acting to destabilize the slope, earthquakes, or weakening of a slope from saturation with water. The water source originates from snow or glacier melt or heavy rains. Human activities can also form landslides from vibrations induced by machinery or traffic, blasting, or other construction activities.