Watershed separation urged to control flow of invaders

[Spiel]

Watershed separation urged to control flow of invaders

 

 

November 19, 2008

Jim Moodie / manitoulin.ca

 

 

CHICAGO-The so-called Windy City is often blamed for being too thirsty-and given its daily draft of two billion gallons of Great Lakes water, via a controversial diversion, you can understand why-but Huron dwellers should be equally concerned about stuff that Chicago is poised to spew up this way.

 

In particular, we might worry about a certain filter feeder of foreign extraction, hearty appetite, and striking heft.

 

The Asian carp, introduced to the Mississippi River in the late 1990s, gets so big (100 pounds is not unusual) that people have actually been injured by this acrobatic invader, which has a habit of flinging itself at high speeds into boats, or across the seats of personal watercraft. If you don't believe us, check out Asian Carp Invasion Pt. 1 on YouTube.

 

The risk to human safety pales, though, next to the threat posed to the overall health of the Great Lakes ecosystem. Known to consume 20 percent of their body weight in plankton per day, these bottom eaters would deplete food sources for other species and potentially decimate commercial and sport fisheries across the basin.

 

For the moment, this remains a hypothetical disaster, but it's not that farfetched. As we speak, the fish is almost literally knocking on Lake Michigan's door.

 

"It's coming up the Illinois River, and it's just 15 miles below the site of the current electric barrier," says Joel Brammeier, vice-president for policy with the Alliance for the Great Lakes, an environmental advocacy group. Carp plucky enough to test the fence will receive a non-lethal jolt, and drift back down the Illinois (which flows toward the Mississippi), where environmentalists and fisheries officials want to keep them.

 

But the barricade may not work indefinitely. "It's been a good deterrent, but it's not a 100 percent solution," warns Mr. Brammeier. "If you rely on a power supply and there's a chance of human error or a natural disaster, something can always go wrong."

 

The present barrier, moreover, is only intended to be temporary, yet a permanent version, while essentially built, "is not yet functional because of safety issues with barge traffic," says Mr. Brammeier. "This has been dragging on at least three years."

 

In the meantime, Mr. Brammeier's environmental organization, with financial help from the Great Lakes Fishery Commission and the Great Lakes Fishery Trust, has devoted a lot of time and study to the problem, and has come up with what it feels is a more foolproof, if seemingly extreme, answer. In a nutshell: re-engineer the Chicago Waterway System so that nothing equipped with fins, shells or feelers has any way of moving between the Great Lakes and the Mississippi.

 

The term the alliance uses is "ecological separation," which it defines, in a 100-page report issued last week, as "no inter-basin transfer of aquatic organisms via the Chicago Waterway System at any time," with a commitment to "100 percent effectiveness."

 

As sweeping as it sounds, the strategy wouldn't put a plug in the transfer of H20 from the Great Lakes to the Mississippi, nor would it necessitate a complete overhaul of waterworks in the area, stresses Mr. Brammeier.

 

"It would not change the way the water flows, or mean we have to re-plumb northeastern Illinois," he says.

 

Some relatively major changes to infrastructure would need to take place, however, and there would be an impact on commercial and recreational boat traffic, Mr. Brammeier admits. "Our proposal is to create a physical separation close to downtown Chicago," he says. "All the water would still be flowing through, but boats wouldn't have the same access to Lake Michigan; they'd have to go through a boat lift and be sterilized." Six areas are identified in the study for possible structural changes, such as new locks and concrete walls.

 

While this might sound like a major reshaping of the Chicago waterscape, it bears remembering that the whole system is unnatural to begin with: over 100 years ago, the watershed here was totally reconfigured to reverse the flow of the Chicago River and link Lake Michigan with the Mississippi via a complex network of canals and rerouted streams.

 

This occurred, in part, to provide water to places south of the Great Lakes, but also to protect Chicago's water supply, which is derived from Lake Michigan. "The system is designed to send storm and sanitary water to the same place, pushing it to the Mississippi River," says Mr. Brammeier.

 

The Great Lakes alliance scheme wouldn't undo that network entirely, but simply stopper up the places where invasive species could sneak through from one watershed to the other.

 

"It wouldn't mean re-engineering the entire city," says Mr. Brammeier. "There are ways of creating a separation that don't require that drastic a solution. All to most of the water flowing to the Mississippi still would."

 

If a bit ended up flowing back into Lake Michigan, that would just be an ecological bonus, in his view. "Any water Illinois can put back into the Great Lakes is a good thing," says the alliance rep.

 

The study released last week is the outcome of a process that began in 2003, says Mr. Brammeier, when the Chicago Aquatic Invasive Species Summit was convened by the city's mayor and the US Fish and Wildlife Service to explore answers to the problem of scary stowaways and fish-farm escapees encroaching upon the Great Lakes, of which the Asian carp is only the latest example.

 

Already, Mr. Brammeier notes, the shipping route at Chicago has contributed to the ingress of such exotic pests as zebra mussels and round gobies. Indeed, more than 150 invasive species have now been identified in the Great Lakes, and many have made their way into the lakes from the south.

 

As costly to governments, and inconvenient to marine traffic, as an "ecological separation" might be to realize, the Alliance for the Great Lakes is confident that most stakeholders, including the shipping industry, are hospitable to the idea.

 

To Mr. Brammeier, it's essential that a solid, long-term strategy is put in place to staunch the flow of invasive species, in particular the Asian carp, before more damage is wrought. "Once this gets in, the effects are potentially catastrophic," he says. "With invasive species, you can't put the toothpaste back in the tube."

 

His organization is now calling upon the US Army Corps of Engineers to grab the tiller for their own "full-scale feasibility study on the same issue," says Mr. Brammeier. "Our study is a first draft at this type of work, and we'll be encouraging the corps to get started on their own plan. We recognize it won't happen overnight; it will take a couple of years and a few to $10 million to do an appropriate study, but we have to get serious about a real solution."

 

The entire report on invasive species prevention, as drafted by the Alliance for the Great Lakes, is viewable online by visiting www.greatlakes.org.