The rugged beauty of bedrock cliffs rising from the
waters of Lake Superior creates a memorable impression
of Minnesota's Lake Superior coast. But unlike the
resistant bedrock that creates beautiful vistas, some
sections of the Minnesota shoreline are erosive sand or
clay banks. Buildings and roads built in these areas are
threatened by the gradual wearing away of the coast by
the powerful waves of Lake Superior.
While shoreline erosion can only be prevented at
great expense, economic losses are minimized by knowing
where and how fast shoreline erosion is likely to occur.
Future problems are avoided by locating new structures
and septic fields back from the bluff line to allow for the
erosion that is expected to occur. Fortunately, the
Minnesota Lake Superior shoreline has had relatively
little development in comparison to other Great Lakes
shorelines, so good planning can prevent future problems.
There are several ways to identify erosion hazard
areas. On-site monitoring of erosion is the most precise
way to measure short-term erosion rates, but can be
misleading as an indicator of long-term hazard if unusual
conditions during the monitoring period cause
uncharacteristically high or low erosion rates. Measuring
shoreline recession from a time sequence of maps or aerial
photos provides longer-term erosion rates. Shoreline
geology also provides an indication of erosion hazard,
because some types of geologic materials are more
resistant to erosion than others. This study combined the
latter two methods to produce maps of long-term shoreline
1 computer file (PDF); 45 pages, maps. Date (1990) is questionable; the last year in the item is 1989.
Johnston, Carol; Sales, James; Bonde, John; Aunan, Tim; Raby, Richard.
Erosion Hazard of Minnesota's Lake Superior Shoreline.
University of Minnesota. Minnesota Sea Grant.
Retrieved from the University of Minnesota Digital Conservancy,
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