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Protecting Great Lakes from Asian carp: Corps sees long waits and high costs

The U.S. Army Corps of Engineers has outlined eight possible scenarios for solving the problem, but no comparative evaluation of the options.

carp catching
U.S. Army Corps of Engineers crews search for invasive Asian carp near Chicago, Aug. 2, 2011.

After more than a decade of watching silver and bighead Asian carp work their way up the Mississippi River and its tributaries toward the world’s most important freshwater resource, it has come to this:

Protecting the Great Lakes with genuinely effective carp barriers will require at least 10 years of construction and probably 25, in the best judgment of the U.S. Army Corps of Engineers, and cost somewhere between $8.3 billion and $18.4 billion.

The Corps’ long-awaited and somewhat overdue response to a congressional directive that it give guidance on the carp problem came out Monday, offering an abbreviated analysis of eight possible options but no opinion as to which might be best.

This caused some consternation in portions of the Great Lakes delegation, particularly over in Michigan, where Sen. Debbie Stabenow has been pushing for the Corps to pick up the pace and provide the sort of analytical foundation on which legislation could be erected.

Eight scenarios, no recommendation

Instead, the Corps outlined eight possible scenarios for solving the problem, no comparative evaluation of the options, and a series of cautionary footnotes as to the highly preliminary nature of its work, four years in the making. A sample:

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The alternatives presented in the report range from continuing current efforts to hydrologic separation with physical barriers. Although the report is not a decision document, it contains design and cost information at the 5 percent design level and includes an evaluation matrix of the alternatives to provide as much detail for decision makers as possible.

Several actions would need to be completed prior to the recommendation of any specific alternative for implementation, including further site-specific design analyses, model certification, detailed evaluations of impacts and mitigation requirements, completion of an environmental impact statement under the National Environmental Policy Act and submission of the report for independent external peer review.

What’s the hurry, after all? There’s still room to hope that continuing detection of Asian carp DNA here and there in the Great Lakes doesn’t actually prove the presence of the fish themselves. It could have been deposited in the poop of carp-eating birds, one of which might have held it while flying 250 miles from the Illinois River to a Lake Superior shoreline near Green Bay.

As for the discovery, reported last month, that fish can get past the electrified carp fences in the Chicago shipping canals by trailing closely behind barges, whose hulls seem to suck electricity out of the water in the immediate vicinity — well, no actual carp were photographed pulling that trick. Those were other fish.

Entire schools of fish, yes, OK. But not Asian carp.

And, really, all that’s at stake is a commercial fishery in the lakes worth $7 billion a year, and a tourism industry centered on aquatic recreation that generates many times that much in annual revenue.

A critical link to sever

The Chicago Sanitary and Ship Canal is not the only place for invading carp to cross from the Mississippi system into the Great Lakes, but it is the largest, the best and the most thoroughly defended by powerful special interests.

U.S. Army Corps of Engineers
From the report, detail of the Chicago Area Waterway System

Those would be the barge shipping industry and its allies, who lost no time this week in sniping at the Corps’ most expensive option — an $18.4 billion, quarter-century construction project to permanently close the canal and erect physical barriers to keep invading carp out of Lake Michigan.

They observed, correctly, that scientists are unwilling to say such a project will absolutely guarantee the lakes’ future as a carp-free zone. On the other hand, it is hard to find a scientist who thinks any program that permits continued operation of the canal stands a very high chance of success.

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Of the seven other approaches assessed by the Corps, four would also require 25 years of construction. These programs would not quite separate the basins, but would place additional physical barriers — including specialized lock systems — at various locations where carp could cross into Lake Michigan.

Depending on the scale of infrastructure involved, costs would range between $8.3 billion and $15.5 billion.

A more modest approach, which would forgo permanent barriers but beef up the electric fences and create some specialized locks, could be completed in perhaps 10 years and cost a mere $7.8 billion.

Two non-construction alternatives round out the list of eight:

  • Maintain the present and ultimately ineffective controls, at a cost the Corps did not calculate but which has been running about $50 million a year over the last four years.
  • Beef up those efforts with a nonconstruction program of public education, ballast water management, poisons, deterrent devices, etc., at an additional cost of $68 million annually.

Reactions in other Great Lakes states

Although the Corps report went virtually unmentioned in Twin Cities media, as best I can tell, it prompted some interesting coverage by newspapers, particularly around the Great Lakes states.

Tom Henry of the Toledo Blade pointed out that regional political divisions are likely to complicate any movement toward a solution, because the commercial fishery is centered on a corridor from Lake Huron through western Lake Erie, where as the political clout is centered in Chicago. Thus, a possible effort to show Chicagoans that there could be collateral benefits to severing the century-old canal:

Henry Henderson, director of the Natural Resources Defense Council’s Midwest office, said the message for Chicago and northeast Indiana will be one of dry basements and cleaner tap water….

Chicago and northeast Indiana have been prone to flooding for years, he said. Separating the watersheds offers an opportunity to modernize Chicago’s water-distribution and wastewater networks, Mr. Henderson said.

Todd Spangler, writing in the Detroit Free Press, picked up on that theme as well:

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Much of the overall cost — $14 billion — [of the $18.4 billion, full -separation alternative] would be tied up in flood management basins and miles of runoff tunnels which would have to be built to reduce increased risks of flooding in the Chicago area. …

Marc Gaden, with the Great Lakes Fishery Commission, noted that much of the costs are associated with flood and wastewater controls in the Chicago area that need to be undertaken no matter what is done about Asian carp.

And he noted that some of the projects would yield returns beyond carp control:

The Corps not only looked at the spread of Asian carp — though it has clearly been the central focus of interest in the report — but also the possibility of invaders in the Great Lakes making their way into the Mississippi watershed, including bloody red shrimp, grass kelp and red algae, the tubenose goby and more.

Writing from Cleveland, the Plain Dealer‘s D’Arcy Egan took a closer look at how those high-tech locks could work, and pointed out that the virtues of closing the Chicago canal flow both ways (but he adopted more Corps acronyms than he might have; translation follows excerpt).

To be used in conjunction with new reservoirs and water storage tunnels, a GLMRIS Lock would completely drain water coming into a lock and dam on the river and replace it with ANS-treated water. Each GLMRIS Lock would cost from $1 billion to $2 billion. Additional reservoirs would be needed to provide water, as well as tunnels to handle storm water and prevent flooding.

The GLMRIS Lock … would allow the removal of silver and bighead carp, the dominant species heading north from the Illinois River. It would also remove other invasive fish, fish larvae and eggs, plants and algae….

The Chicago Waterway System is a two-way street, said [Corps spokesman Dave] Wethington. USACE is also trying to keep ANS from Lake Michigan and the Great Lakes from flowing into the Mississippi River Basin. That includes the Eurasian ruffe, an invasive species once confined to Lake Superior whose DNA has recently been discovered in southern Lake Michigan. Invasive zebra and quagga mussels from the Great Lakes already contaminate the Mississippi River Basin, and continue to spread around the U.S.

When Egan says GLMRIS, he’s using the Corps’ acronym for this project; ANS is what the Corps calls aquatic noxious species, and USACE is what the Corps calls itself.

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The Corps will conduct a series of seven public meetings on its study beginning today in Chicago. A Twin Cities session will be held on Jan. 27, from 4 to 7 p.m. at the headquarters of the Minnesota Valley National Wildlife Refuge in Bloomington, near the airport. The full schedule is here.

A summary of the study, whose unglamorous GLMRIS label stands for Great Lakes and Interbasin Mississippi River Study, can be read here.