Historical Breakwaters on Lake Champlain, New York/Vermont History, Inspection and Preservation

PB Ports & Marine, Inc., a subsidiary of Parsons Brinckerhoff Quade & Douglas, Inc. (PB), was commissioned by the United States Army Corps of Engineers, New York District (USACE), to perform a condition survey of two existing historical breakwaters located on Lake Champlain; one in Burlington, Vermont and the other in Plattsburgh, New York. Both breakwaters are oriented roughly parallel to the shoreline, approximately 300 meters from the shore and protect public harbors serving recreational boats. The Burlington Harbor is located on the Eastern Shore of Lake Champlain, about 65 kilometers south of the Canadian Border. The Plattsburgh Harbor is located on the Western Shore of Lake Champlain, about 40 kilometers south of the Canadian Border. The crest elevation of the existing breakwaters varies from 0.9 meters to 1.8 meters above the Mean Lake Level (MLL) at Burlington. Therefore, the breakwaters occasionally become submerged and often experience wave overtopping during high water periods. On average, Lake Champlain freezes on February 11 and opens to navigation on April 8. The ice is usually thicker on the harbor side due to the combined effects of weaker wave action, relatively shallow water in the harbor and trapping of ice by the breakwater. There are times when the harbor side is frozen while there is no ice on the lakeside of the breakwaters. Both breakwaters, built at the end of the 19^th century, are comprised of timber cribs filled with stone. Concrete superstructures built at the breakwater ends support beacon lights. Presently, the original cribs of both breakwaters are severely deteriorated. Several repairs have been performed during the 19^th and 20^th centuries to keep the breakwaters functional. Those repairs consisted of the replacement of deteriorated crib portions and placement of riprap and heavy armor stone on the lakeside of the breakwaters. However, deterioration of the timber on the harbor side is continuing. In some places, the crib walls have collapsed, causing the release of stone fill.