OSWEGO — Continued high water levels could mix with fall and winter storms to cause significant erosion and shoreline damage, the U.S. Army Corps of Engineers warns, recommending property owners keep protective measures in place for the foreseeable future.
Lake Ontario water levels hit a record-high 249.08 feet in mid-June — just two years after setting a previous high — but the water has receded almost 17 inches in the last two months to 247.67, which is still nearly two feet above average for this time of year. Federal officials are forecasting above average water levels through at least early 2020, and warning heavy winds and wave action could continue to cause damage throughout the Great Lakes.
In addition to Lake Ontario, each of the other Great Lakes are at or near record-high levels, including Lake Superior and Lake Erie, which feeds directly into Lake Ontario.
According to the U.S. Army Corps of Engineers (USACE), the 2019 spring and summer seasons have experienced record high water levels that are likely to remain significantly above average during the upcoming fall and winter seasons.
USACE Chief of Watershed Hydrology Keith Kompoltowicz said it’s very difficult to put any sort of for sure statement on what we can expect next spring. He said “it’s very difficult to say just how long” high water levels would remain in place, but the latest forecast anticipates high water into early 2020.
“Even though the lake is declining, the lake remains very high compared to average and the impacts from high water are likely to continue for the foreseeable future,” Kompoltowicz said. “Our forecast window is only six months and that latest forecast does show the lakes remaining well above average for the next six months.”
Forecasts from the USACE and the International Joint Commission (IJC), which oversees shared U.S.-Canadian waterways and has been blamed for the high waters on Lake Ontario, indicate the lake is likely to remain above average through the end of 2019. IJC forecasts note under average water supply conditions Lake Ontario would sit around 245.5 feet at year’s end, though under wet conditions it could be more than a foot higher.
USACE Colonel Greg Turner said though water levels are trending downward, there’s still a significant potential various Great Lakes could hit records for a given month. Turner said heading into fall, winds and wave action historically pick up, and the USACE is concerned the heavy waves and winds could exacerbate the damage from high water levels.
Officials said shoreline property owners should keep temporary protections in place until next year.
The Army Corps says beyond six months, it’s difficult to say with certainty how high the water levels might be due to the decreasing certainty of long-term forecasting. Officials, however, said it is safe to say that unless the region experiences very dry conditions moving forward water levels would remain very high.
The USACE notes water levels are primarily determined by regional climatic conditions that influence the net basin supply of water into each lake. Net basin supplies include precipitation over the lake and runoff from the surrounding watershed.
According to the USACE, over the past several years, the net basin supplies have, more often than not, been above average on all the Great Lakes. The Army Corps notes the dramatic rise in water levels followed a decade of mostly below average net basin supplies that resulted in an extended period of low water levels.
Officials attributed the dramatic rise in waters levels throughout the Great Lakes regions to heavy precipitation over several years. Kompoltowicz said “lake levels primarily are driven by Mother Nature” and the amount of precipitations and runoff from the surrounding land.
“It’s been wetter than average for the most part over the past six to seven years — that has really been kind of a starting point of this repetitive cycle of rising levels from one year to the next,” Kompoltowz said. “Then very recently, in 2019, we had a very healthy snow pack on the ground in the Great Lakes basin heading into the spring — that was on top of already saturated soils from a wet fall of 2018 — and then unbelievable amounts of rainfall in the spring.”
Kompoltowicz said all those factors combined to create quickly rising lake levels this spring that culminated in record-high water levels, noting it was “a Great Lakes-wide issue.”
Turner noted the Great Lakes weren’t the only region that suffered from heavy precipitation, pointing to a nationwide trend that impacted the Ohio, Arkansas and Mississippi rivers. According to the National Oceanic and Atmospheric Association (NOAA), the Mississippi River has flooded each year since 2016 and broke a more than 100-year-old record, with 211 days above flood stage — the longest known flood on record on the lower Mississippi, from December 2018 to August 2019.
Oswego Mayor Billy Barlow expressed concern about high water levels causing winter damage, saying the high lake levels are “rendering the breakwall almost ineffective,” noting “sizable waves from a storm, especially winter storms, might roll right over or through the breakwall in some places” and leaving the harbor largely unprotected.
Barlow said the USACE should expedite the repair schedule, adding in some places the breakwater is beyond repair and a replacement may be necessary.
“Storms and waves that previously weren’t a huge danger to the marina are now more serious and rolling into the harbor,” the mayor said. “Sooner or later there will need to be serious investment in the breakwall if its goal is to offer adequate protection.”
USACE spokesperson Andrew Kornacki said infrastructure across the Great Lakes must be addressed, noting there is “a lot of aging infrastructure” the Army Corps’ operations and maintenance program is frequently assessing. Kornacki said a submerged breakwater can present a potential hazard to navigation, but noted “funds are very scarce to maintain and update the infrastructure.”
Kornacki said there were no plans for a significant revamping of the local breakwater, but said Oswego in recent years has seen dredging and repairs to the breakwater to ensure it continues to function in the proper manner.
USACE officials are seeking funding for the so-called Great Lakes Coastal Resiliency Study, which, if funded, would form a partnership between the eight Great Lakes states, Army Corps, NOAA and other federal agencies to investigate opportunities to improve resilience in coast environments and create a plan that identifies vulnerable areas and recommends measures to decrease the risk of shoreline damage.