Monday, March 25, 2013 at 02:24 PM
Stateline Midwest ~ February 2013
In December, water levels on lakes Michigan and Huron reached an all-time recorded low. And concerns about this trend have never been higher — as reflected in much of the discussion at a January meeting in Chicago that explored the new Great Lakes Water Quality Agreement.
For the first time in its 41-year history, the binational pact makes adapting to climate change a priority for action on both sides of the border.
Though they have always fluctuated, the recent low readings in lakes Michigan and Huron have led many to conclude that “we have reached a tipping point,” noted John Nevin of the International Joint Commission (IJC), with warmer air and water temperatures leading to increased evaporation of Great Lakes waters.
“The commission is very concerned about it,” Nevin said at the meeting, which was sponsored by the IJC as well as the Alliance for the Great Lakes and Consulate General of Canada in Chicago.
But can concerns about lower water levels and other climate-change impacts be translated into meaningful action?
As many meeting speakers and participants noted, part of the challenge for Great Lakes policymakers is taking action in the face of many unknowns — how much the climate will change in the coming decades, for example, and how it will impact the ecosystem.
Current forecasts of lake levels, Nevin said, show that they will be lower than normal over the next 30 years, but remain within the six feet of fluctuating levels recorded during different periods of the 20th century.
“Beyond 30 years,” he said, “ it is unknown.”
Lower water levels affect boaters and shippers, shoreland owners and users, and Great Lakes habitat and wetlands.
At least over the short term, the low water levels have led to calls for more state-level investments in the dredging of ports and harbors. Another potential government response is to make structural changes in the St. Clair River — a move that would boost water levels in lakes Michigan and Huron but also raise concerns about the impact in other parts of the basin.
Rise in algal blooms, sewage overflows among other effects
Low water levels are only one of the many potential consequences of climate change.
Higher temperatures have also been identified as one reason for the rise in Lake Erie of harmful algal blooms, which are more likely to occur in warmer waters.
Combating these algal blooms has long been a binational priority due to their impact on the Great Lakes ecosystem and fishing industry, as well as the threat they pose to beaches and drinking water sources.
The policy response on both sides of the border has been to limit the amount of phosphorus and other nutrients entering the lakes. Limiting runoff from industrial and sewage-treatment plants led to significant progress under previous agreements.
“But now we’re in a new era of serious backsliding,” Jim Bruce, a longtime Canadian leader on Great Lakes policy, said at the meeting.
He cites warmer water temperatures and non-point source pollution from agricultural land as two leading contributors to the algal-bloom problem in Lake Erie.
Under the recently updated binational agreement, new “loading targets” will be established to limit the concentration of phosphorus in Lake Erie. The targets will be in place within three years and a framework for meeting them will be in place within five years. (Targets will also be set for the other four lakes, but a specific timetable is not set.)
As a result, states will be asked to establish new rules, programs and laws to reduce the amount of nutrients entering the Great Lakes.
Bruce noted, too, another significant change in the Great Lakes region’s climate — “when it rains, it pours.”
Between 1958 and 2007, the number of heavy downpours in the region has increased 31 percent (there was little change in light or moderate precipitation during this period). This trend is expected to continue, leading to more sewage overflows and more pollution entering the lakes.
For states, this will mean more pressure to finance upgrades to their water infrastructures.
“We can’t stand still and do nothing [despite the many unknowns],” said Dereth Glance, a U.S. commissioner for the International Joint Commission.
She said governments on both sides of the border will have to establish more adaptive-management strategies: bolster scientific monitoring and research of the Great Lakes, and then use the findings to revise their policies.