DULUTH — The level of Lake Superior dropped a little more than 1.5 inches in December, only half its normal decline for the month, remaining precariously close to record high levels and spurring continued erosion problems along its shoreline.
That was the report Friday, Jan. 3, from the International Lake Superior Board of Control that warned lakeshore residents to “prepare for potentially severe coastal impacts, especially during periods of strong winds and high waves.”
Lake Superior is a whopping 13 inches above its normal Jan. 1 water level and a full 4 inches above the Jan. 1, 2019 level one year ago.
The lake is less than an inch from its all-time record high January level set in 1986 as an unprecedented six-year wet period continues.
Heavy rain and snow and continued free-flowing rivers still not locked in ice contributed to the big lake’s slower-than-usual decline.
“Lake Superior and Lake Michigan-Huron remain near record-highs for this time of year, and although they are expected to continue their seasonal declines in January, levels are expected to remain high over the next several months and may again exceed record-highs if wet conditions continue in 2020,’’ the board said in its monthly report. “As a result, there will continue to be a significantly increased risk of shoreline erosion, lakeshore flooding and coastal damages through the winter.”
The news comes in the wake of two major gale-force storms that battered the western end of Lake Superior in recent weeks, one just after Thanksgiving and another days after Christmas, sending waves pummeling the shoreline and spurring major erosion. Park Point residents in Duluth continue to see their sand beach crumble into the lake as South Shore clay sloughs into the water and even North Shore gravels erode.
The current outflow for Lake Superior is set at 86,874 cubic feet per second, well above the average outflow for this time of year and above the long-term plan for the lake. Some Lake Superior shoreline residents have complained that not enough water is being let out of the big lake through control structures on the St. Mary’s River in Sault Ste. Marie.
But Charles Sidick, hydrologist for the U.S. Army Corps of Engineers in Detroit who oversees Lake Superior water levels, said the outflow is near the maximum safe level for the man-made structures. The outflow also is within the plan set by agreement between the U.S. and Canada.
Moreover, releasing more water from Superior faster will only compound the problems downstream, such as on Lake Michigan where an entire Muskegon County, Mich., waterfront home fell into Lake Michigan on New Year's Day due to high water erosion.
Lakes Michigan-Huron are now above the previous January record by 1.7 inches and were an incredible 37 inches above average for Jan. 1 and 17 inches above the level on Jan. 1 one year ago.
“For every (resident) on Lake Superior complaining about not releasing enough water, there is another one on Lakes Michigan-Huron who wants us to release less,” Sidick said. “There's also the issue with the control structure itself. We could maybe release another 120 cms or so safely, but more than that and we could cause much damage to the compensating works due to the ice. The hydropower plants are also passing as much as they can.”
Lake Superior generally declines from October through March and then rises from April to September. The all-time record high occurred in October 1985, although some monthly records have been set since then. The all-time record low occurred in April 1926.
Just a decade ago several Great Lakes were near all-time low levels. Now, nearly six years of high water has been good news for shippers, with Great Lakes freighters able to carry full loads and not worry about bottoming out in some ports and channels. (As recently as 2013 some freighters were leaving ports less than full because of low water levels.) But the high water since 2014 has exacerbated erosion issues, with much less beach and other shoreline buffer against wind-whipped waves, allowing storms to cause millions of dollars in damage to the Duluth Lakewalk and other waterfront areas, damage that probably wouldn't have been as bad in low-water conditions.