Coping with the Effects of High Water Levels on Property Hazards: North Shore of Lake Superior

Abstract

Property hazards associated with the 1985–86 high-water levels on the north shore of Lake Superior between Duluth, Minnesota, and Thunder Bay, Ontario, are examined. Data on composition of bluff/shore materials, recession rates, property setbacks, and existing shore protection structures were obtained from questionnaire surveys. Estimated long-term bluff/shoreline recession rates vary from less than 3 m to more than 15 m over a minimum period of 5 years, with a substantial amount of erosion occurring during the 1985–86 high water period. Approximately 39 percent of the respondents protected their properties with structural devices, but many were ineffective. Many respondents perceived lower water levels as a higher priority than providing shore protection structures. However, human ability to manipulate the levels of Great Lakes is limited, since lake levels are dependent primarily on climatic cycles. Because of the limitations on controlling water levels, master plans for land use regulations should be developed to prevent or minimize future encroachment of properties upon flood- and erosion-prone reaches of the shoreline.