Photo Credit: Karl Jansen
This photo shows the outflow of a dredging operation in St. Joseph, MI. The vessel in the background is sucking up material from the bottom of the lake to deepen the channel leading into the harbor. The material is then pushed through a pipe to the shoreline, where it is deposited. Dredging in this manner serves to maintain the depth of waterways for commercial vessels, and to sustain the shoreline in some capacity near popular beach areas.
Photo Credit: Alex Mead
Pictured above is a custom built crane barge called the Left Coast Lifter. It was originally built to assist in the construction of the Bay Bridge East Span replacement connecting Oakland, California and San Francisco, California. The Bay Bridge East span project was completed in September 2013 and the Left Coast Lifter was transported via the Panama Canal to New York State for use on the replacement Tappan Zee Bridge project over the Hudson River.
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.