Great Lakes, Great Peril
Low-volt jolt: Carp barrier ready, but can't be operated at peak strength
The man in charge of the Army Corps of Engineers' electric Asian carp barrier says it looks like the $9 million contraption is ready to be turned on, but not at a power level biologists say is necessary to actually stop all sizes of fish.
That means the door to the world's largest freshwater system will remain cracked open to the giant filter-feeding fish that could ruin the Great Lakes' multibillion dollar fishing industry, ravage their ecology and threaten recreational opportunities such as water skiing because of their dangerous penchant for hurtling out of the water when agitated by the whir of a boat motor.
The fish have already overwhelmed stretches of the Mississippi and Illinois rivers and have migrated to within about 15 miles of the barrier on the Chicago Sanitary and Ship Canal.
The electric gate was finished in early 2006, but aside from testing, the Corps has refused to turn it on because of worries about the dangers the electrified water could pose to barge operators and pleasure boaters plying the manmade waterway that links Lake Michigan to the Mississippi River.
On Oct. 31, the eight Great Lakes governors wrote the Army Corps and U.S. Coast Guard seeking answers. The letter followed an Oct. 5 Journal Sentinel story showing about $1 million of the $9 million so far spent on the project has gone toward more than two years of safety tests and other work to make the barrier safer. Yet despite all that effort, the federal government still wouldn't say when - or even if - the barrier would ever be activated. Now the Army Corps says it looks like it's ready to finally flip the switch.
"I think it's probably ready to go," Chuck Shea, barrier project manager for the Army Corps, said last week. "We've done a lot of tests, and recent results appear fairly promising."
But there is a catch: At this point the Corps would allow the barrier to operate at only about one quarter of its maximum power, or one volt per inch. That is the strength of a smaller "temporary" barrier currently operating in the canal at a level that biologists agree is not strong enough to permanently keep the carp out of the lakes. That is also the level the Corps promised the barge industry it would not exceed in a 2006 agreement allowing the new barrier to be turned on in an emergency if the temporary barrier fails, according to documents the Journal Sentinel obtained through the Freedom of Information Act. Barge industry leaders fear that operating the barrier any higher than one volt per inch poses too much of a risk for sparking between barges, or for anyone who might fall overboard.
The Corps and Coast Guard say they still need more studies to determine if the barrier is safe to operate at its maximum power level of four volts per inch, but the one volt per inch level should be enough to protect the lakes from the supersized carp dubbed the 100-pound zebra mussel because of its ability to vacuum nutrients from the water.
The science says otherwise.
A throttled-down new barrier should repel larger adult fish, but little juvenile fish are less affected by electric currents and therefore need a bigger shock, according to laboratory research.
Shea said last week that the new barrier was always designed to operate at a "base" of one volt per inch and would be turned up to four volts only "if smaller fish become a concern in the future."
That's news to members of the advisory panel of scientists that has been helping the Corps get the barrier built.
"It was my impression that it was designed to operate at four volts per inch," said Phil Moy, a former Army Corps employee who now works for UW Sea Grant and is co-chair of the barrier advisory panel.
Panel member Irwin Polls said increasing the voltage was a major reason to build the new barrier in the first place.
"I do not remember anyone from the Corps mentioning that (the new barrier) would only operate at a higher voltage if young fish were present in the area," said Polls, a consultant who previously worked as a biologist for the Chicago sewer district.
Indeed, the Corps' own documents from 2006 note that the new barrier "will be operated at higher field strength, four volts per inch versus one volt per inch for the temporary barrier."
The Army Corps has been wrestling with the voltage issue since 2004, when a barge operator reported electrical arcing between vessels at the temporary barrier. That could be a potentially hazardous situation because many of the boats carry flammable materials.
In 2005, records show, the Coast Guard asked the Army Corps to shut the temporary barrier down so safety tests could be conducted, but the Corps declined to leave the Great Lakes unprotected from the carp, and instead settled on new set of rules for boaters in the barrier zone, including a lifejacket requirement and no hitching or unhitching barges.
There have been no new safety incidents reported.
A big problem for the new barrier is that it was built just upstream from where barges unload their coal at a power plant. The Corps has spent $330,000 on a system to keep electricity flowing out of the barrier zone and into the coal loading area, and it appears to have worked - provided the barrier operates at only one volt per inch.
Work, meanwhile, is about to begin on a twin barrier just upstream from the new barrier. Its designers maintain that the new two-barrier system was always designed to work in tandem as a single unit, with the upstream barrier at times operating at a higher level and the existing new barrier typically operating at one volt per inch.
They say the new upstream barrier will be turned up above one volt if small carp are determined to be in the area, but that should happen only for a brief period each year after the annual spawn because the fish grow so fast.
That is nonsense, according to biologists who make their living studying Asian carp. The fish spawn throughout the warm months, and their growth rate can vary widely depending on how much food is in the river.
"You can find fish of any size in the river at any time of year," said Duane Chapman, a biologist with the U.S. Geological Survey.
And if the fish are smaller than about five inches, tests have shown one volt simply will not repel them all.
"Until we got close to four volts per inch, we were not overly effective at stopping small fish," said University of Nebraska biologist Mark Pegg, who conducted shock studies on the fish between 2002 and 2004.
Great Lakes Fishery Commission biologist John Dettmers said he has personally witnessed other species of small fish swimming just fine through the temporary barrier, and he calls it "revisionist history" that the Corps says the new barrier's normal operating level was never intended to be any higher than the temporary barrier.
"It's extremely disturbing that the Corps believes one volt per inch is sufficient to protect this very important waterway," Dettmers said.
He also said it is folly to think the barrier can be turned up only periodically to stop juvenile fish.
"We know small fish can be in the (river) almost the entire year, and it's going to be very difficult to determine exactly where those fish are at any time," he said.
More studies planned
Coast Guard officials in charge of safety on the canal say they are wrestling with a complex issue.
"The fish barrier must both prevent invasive species from migrating into Lake Michigan and also minimize the very real risk it poses to the lives and health of those many recreational and commercial waterways users who regularly pass near and over it," said Capt. Bruce Jones, the Milwaukee-based commander of the Coast Guard's Lake Michigan sector.
But advisory panel co-chairman Moy said he worries that biology is taking a backseat when the barge industry talks to the Army Corps and Coast Guard about how to best operate the new barrier.
"I'm just a little afraid that some of the science and invasive species biology might be left out of some of those discussions," Moy said. "I don't know of any biologists that have been involved with the discussions between the Corps and the Coast Guard and river carriers. Somewhere, some of the information is apparently not getting to the top."
While the carp have been mysteriously stalled about 15 miles below the new barrier for the past couple of years, biologists say that after a big spawning year they typically make significant gains in their northward migration. The fish were imported to Arkansas from Asia over three decades ago and escaped their containment ponds.
This past year the carp had a big spawning season.
Still, nobody should expect the barrier to be turned on to levels that will repel all the little fish anytime soon.
The Corps might be able to turn on the new barrier at the one-volt level in the coming weeks or months, but Shea said it "will not be operated at higher voltages until the higher voltage tests are completed, reviewed, and approved by the Corps and Coast Guard."
History suggests that could take years.
And that has a growing number of people demanding faster action.
"Failure to use that barrier as it was intended to keep the carp out of Lake Michigan is not an option," said Illinois Lt. Gov. Pat Quinn, who also serves as the chairman of the Great Lakes Commission.