Can Asian carp invasion be averted?

In December 2009, an environmental emergency brigade of 450 Americans and Canadians descended on Romeoville, Ill., armed with nets, boats, and thousands of gallons of poison. The urgent, 20-agency response was brought on by recent environmental DNA (eDNA) tests indicating that Asian carp were closer to invading Lake Michigan than previously thought. The tests detect traces of Asian carp DNA in water samples within a 48-hour period.

One of the 450 who dropped everything and headed to Romeoville was Phil Moy, a fisheries and aquatic invasive species specialist with the University of Wisconsin Sea Grant Institute. Fifteen years ago, Moy served as the first manager of a project to erect an electric barrier in the Chicago Sanitary and Ship Canal to repel foreign fish.

Chicago dug this canal more than a hundred years ago to manage wastewater, and its construction joined two major ecosystems that until then had remained isolated. Over the last several decades, Asian carp that escaped from Southern aquaculture and wastewater facilities have been moving up the Mississippi to the Illinois River, and the canal connecting it to Lake Michigan is an ideal pathway for the fish to advance into the Great Lakes.

In December, scheduled maintenance required temporarily shutting down part of the barrier. Because eDNA tests showed Asian carp advancing, a 5.7-mile section of the canal was treated with rotenone, a fish poison, to ensure that no carp would breach the barrier during the maintenance.

Moy was on hand-and often on a boat-during the seven-day effort that required coordinating all of the state and federal agencies involved using the Incident Command System, a procedure similar to that used to coordinate efforts to fight large wildfires in the West.

Moy has remained active on the electric barrier project as co-chair of its advisory panel. However, he admits that the barrier is only a temporary solution. Ultimately, he said, the only sure way to keep Asian carp and other invasive species out of the Great Lakes is to permanently sever the link between the Mississippi River and Great Lakes basins.

“I really think that’s the direction we have to go,” Moy said.

What Would Carp Need?

The four species of Asian carp-bighead, silver, black, and grass-pose a significant threat to the Great Lakes commercial and sport fisheries, collectively valued at more than $7 billion annually.

The filter-feeding fish can grow to be more than 100 pounds, and they are capable of daily gobbling up 20 percent of their weight in plankton, the tiny organisms that provide the foundation of the Great Lakes fishery food chain.

In addition, motor boat engine noise startles silver carp, causing them to shoot up in the air as high as 10 feet. Airborne silver carp have injured several boaters on the Mississippi and Illinois rivers-where Asian carp, imported from Taiwan in the 1970s to consume the waste in aquaculture and wastewater systems, have elbowed out native fish to become the dominant species in many areas.

Although there’s no question the carp pose a threat to Great Lakes fish and boaters, Moy said a successful Asian carp invasion is by no means a sure thing. “It takes some specific habitat for them to do really well,” he said.

Scientists estimate that the carp need access to a river with a deep, free-flowing main channel in order to successfully reproduce. If their eggs settle to the river bottom before hatching, the embryos will suffocate and die.

“One hundred kilometers-about 63 miles-is roughly the distance needed to provide enough current to keep the fish’s fertilized eggs suspended in water while they incubate,” Moy said. Out of thousands of tributaries that feed the Great Lakes, only 22 on the U.S. side (four in Wisconsin) meet this criterion. Adding another criterion-the availability of quiet, fertile backwater areas where the newly hatched fish larvae can eat and mature-reduces the list even more.

However, before they can reproduce, the fish would need to find each other within more than 94,000 square miles of the Great Lakes. While a few bighead carp have been captured in Lake Erie, probably due to someone releasing them there, they have yet to multiply into any significant numbers.

Indeed, Moy said it’s all about numbers now, and that’s why the electric barrier is still important.

“We have to keep the numbers as low as humanly possible,” he said. “Even if there are a few Asian carp upstream of the electrical barrier, there is absolutely no assurance that they’ll be able to establish a population.”

However, Moy said that the electrical barrier is not a permanent solution, because it depends on the fish reacting predictably to a technology that could potentially fail. In addition, it doesn’t do anything to protect the Mississippi River basin from small, floating invasive species coming from the Great Lakes, such as quagga mussel larvae.

“We really need to establish a two-way separation in order to really protect both basins,” he said.

Restoring the Natural Separation?

Accomplishing this would be challenging, but possible, Moy said, and shutting down the canal locks would only be one step.

The Des Plaines River runs parallel to the Sanitary and Ship Canal, and flooding in 2008 sent water from the Des Plaines overland into the canal upstream of the barrier. The Army Corps is now investigating how best to address this “leaky” spot.

Other potential leaks around the Great Lakes would likely need to be addressed, too. A mere two miles of marshy, flat terrain separates the Mississippi and Great Lakes basins at Portage, Wis., where a canal was dug in 1851 to connect the Wisconsin and Fox rivers. Asian carp have now advanced as far north as Lake Pepin in the Mississippi River, well upstream of its confluence with the Wisconsin River.

Moy and other biologists worry that Asian carp could drastically change the Great Lakes food chain, just as a string of other aquatic invasive species have caused sweeping changes over the last century.

In the 1800s, blood-sucking sea lamprey invaded the lakes through locks and shipping canals connecting the Great Lakes to the Atlantic Ocean. The lamprey’s introduction caused a major collapse of lake trout, whitefish, and chub populations during the 1940s and 1950s. The absence of large predator fish like lake trout caused an explosion in the population of small, silvery alewives, which were introduced to Lake Erie in the 1930s and soon spread throughout the Great Lakes. Then, to fill the gap left by lake trout, fisheries agencies introduced coho and Chinook salmon to control alewife numbers and provide an exciting sport fishing experience.

Canada and the United States spend approximately $18 million a year to control sea lamprey numbers using a toxin that specifically targets the lamprey. Moy said a similar effort might have to be launched for Asian carp if they successfully invade the Great Lakes, although a carp-specific toxin has not yet been developed.

Kathleen Schmitt Kline is a science writer at the University of Wisconsin Sea Grant Institute, which supports research, education, and outreach dedicated to the stewardship and sustainable use of the nation’s Great Lakes and ocean resources. Visit seagrant.wisc.edu for more on Asian carp, including video of the fish.

Asian Carp Facts

The common term “Asian carp” includes four types of carp native to Asia that have been introduced in the United States over the last three decades: bighead, silver, black, and grass.

Size: Commonly 24-30 inches and 3-10 pounds, but capable of growing to more than 50 pounds.

Preferred habitat: Large warm-water rivers and impoundments.

Threat: Asian carp are tremendous filter feeders that would likely out-compete many native fish if they become established in the Great Lakes. Silver carp jump out of the water in response to outboard motors and can seriously injure boaters.

TIMELINE

Early 1970s Asian carp are imported from Taiwan to the United States for cleaning aquaculture ponds and sewage treatment facilities. Flooding allows them to escape into the Mississippi River basin.

1995 As Asian carp make their way up the Mississippi River to the Illinois River, an advisory panel forms to aid the U.S. Army Corps of Engineers in finding an environmentally sound method for preventing the spread of the carp and other aquatic nuisance species through the Chicago Sanitary and Ship Canal.

1997 Barrier Advisory Panel recommends an electric barrier as the best approach with the least number of drawbacks. However, the panel notes that no approach relying on animal behavior or a technological solution, as opposed to a physical separation, could be 100-percent effective in stopping the movement of aquatic invasive species through the canal.

April 2002 The Army Corps begins operating the first electrical barrier (Barrier I) as a demonstration of a new technology for preventing the spread of aquatic nuisance species. The barrier operates at a strength of one volt per inch, strong enough to repel most adult fish, but possibly not strong enough to repel smaller juvenile fish.

Based on monitoring and testing of Barrier I, a second, more permanent barrier (Barrier II) is authorized. Barrier II is a similar electric field barrier that covers a larger area within the canal and is constructed to last longer. It consists of two sets of electrical arrays and control houses, known as Barriers IIA and IIB. Each control house and set of arrays can be operated independently, but the ultimate goal is to operate both at the same time.

May 2006 Barrier IIA is completed, but due to safety concerns, it sits idle for nearly three years.

2007 Congress authorizes the Army Corps to complete Barrier II, to upgrade Barrier I and make it permanent, and to operate the barrier system at full federal cost.

September 2008 Flooding in the Chicago region sends water from the Des Plaines River tumbling over the narrow strip of land between it and the Sanitary and Ship Canal at several locations above the barrier site.

October 2008 Barrier I is shut down for maintenance. Repairs are made to allow Barrier I to remain in service for several more years until Barriers IIA and IIB are fully functional.

April 2009 Barrier IIA begins operating full-time at a strength of one volt per inch.

July 2009 Environmental DNA (eDNA) testing detects Asian carp DNA just south of the Lockport Lock, much closer to the barrier than previously believed. The eDNA test detects traces of Asian carp DNA in water samples within a 48-hour period.

August 2009 In response to the eDNA tests, the strength of Barrier IIA is increased to two volts per inch.

September 2009 Asian carp DNA is detected approximately one mile south of the barrier.

October 2009 Asian carp DNA is detected in the Cal-Sag Channel and Calumet River, beyond the electrical barrier.

December 2009 A 5.7-mile section of the canal is closed while scheduled maintenance on Barrier IIA takes place. Barrier I remains active. However, because Barrier I may not be effective in deterring juvenile fish, a fish toxin called rotenone is applied to the canal between the barrier and the Lockport Lock and Dam. At least 450 people from 20 agencies from the Great Lakes states and Canada report to Romeoville, Ill. to assist with the effort.

January 18, 2010 Asian carp DNA is detected in water samples taken Dec. 8, 2009, in the Calumet Harbor in Lake Michigan.

Reproduction in Rivers

If a substantial population of Asian carp establish themselves in the Great Lakes, scientists predict they will have to reproduce in river systems with 100 kilometers or more of open channel. There are 22 such rivers on the U.S. side of the Great Lakes. Four Wisconsin rivers could be especially favorable environments to carp reproduction-the Bad, Manitowoc, Nemadji, and Sheboygan rivers.

Source: April 12, 2005 U.S. Geological Service report submitted to the U.S. Department of Fish and Wildlife

Great Lakes ice rhythms

Its hull a small black spot defiant against the surrounding field of white, the Coast Guard’s 140-foot Mobile Bay has cut through ice encumbering the waters of Green Bay each winter for three decades.

Icebreaking is such a massive task, the Coast Guard calls it Operation Taconite-keeping the way clear for commercial vessels in Lakes Michigan and Superior, the St. Mary’s River, and the Straits of Mackinac.

But aside from the Coast Guard-plus the occasional polar bear plunger or diehard ice fishermen-few humans pay close attention to the complex rhythms of lake ice building and receding that play out across the Great Lakes annually.

George Leshkevich, however, a scientist at the National Oceanic and Atmospheric Administration’s Great Lakes Environmental Research Laboratory (GLERL) in Ann Arbor, Mich., has been studying lake ice for several decades.

According to Leshkevich, differences in the lakes’ depths and regional air temperatures affect their potential to develop ice cover. Lake Erie, for example, is the shallowest of the lakes and typically sees the most extensive ice cover each winter, relative to its surface area. Lake Superior, farthest north and subjected to colder temperatures, is next on the list, followed by Lakes Huron, Michigan, and Ontario.

The extent of ice cover on the Great Lakes can also vary greatly from year to year, Leshkevich said.

For example, between 1963 and 2001, the maximum extent of ice cover on Lake Michigan over the course of a single winter ranged from 13 percent (in 1963-64) to 96 percent (in 1978-79) of the lake’s surface, according to one study. The average over that same period was 40 percent.

Along with such year-to-year fluctuations, the Great Lakes have seen an overall downward trend in winter ice cover over the last 30 to 40 years, said Leshkevich. That decline has coincided with an overall increase in global air temperatures.

Both natural variability and human-induced climate change can influence Great Lakes ice cover, said Leshkevich and fellow GLERL scientist Jia Wang. However, the more dominant influence is natural variability, which drives the year-to-year fluctuations in ice cover, Wang said.

“Our region is very complex because it is affected by two [natural] climate patterns,” said Wang. One pattern comes from the Pacific and brings either warmer “El Niño” or colder “La Niña” temperatures to the Great Lakes region. A second pattern that comes from the Arctic likewise affects the region’s temperatures with its warmer “positive” and colder “negative” phases.

The Great Lakes generally have lower ice cover in years when both the Pacific and Arctic patterns are warm, and higher ice cover in years when both patterns are cold, Wang said. When the patterns differ, they either moderate each other’s effects or the stronger pattern dominates. Last winter, the patterns combined to bring to the Great Lakes one of the more extensive ice covers of the past decade, a period during which ice cover was generally low.

Regional & Local Effects

Lake ice affects both the environment and the economy of the Great Lakes. Ice is good at reflecting sunlight, so its presence decreases the ability of the lakes to absorb heat and keeps them colder, said Jay Austin, a scientist at the University of Minnesota-Duluth’s Large Lakes Observatory.

What’s more, said Austin, “the effect of ice is felt long after the ice is gone. The amount of ice during the winter can significantly affect lake temperatures throughout the summer.” His research shows that summer surface water temperatures of the northern Great Lakes-Michigan, Superior, and Huron-generally are warmer after winters with low ice cover, and colder after winters with high ice cover. He believes this is because ice cover delays the springtime stratification of the lake into layers of different densities, a phenomenon that promotes rapid warming of the surface layer in the summer.

Everything from algae to fish could be impacted by changes in lake temperatures and stratification that result from long-term changes in ice cover, according to Austin’s study.

Ice affects other aspects of the environment, too. In shallow areas, it can help protect the eggs of whitefish and other fall-spawning fish from currents and waves generated by strong winter winds. Ice cover also inhibits evaporation by shielding the lakes from dry, cold winter air. As a result, lake levels are often lower after winters with low ice cover, and higher after winters with high ice cover, said Wang.

Ice has implications for Great Lakes industries such as power production and shipping. Ice jams that form on the rivers connecting the lakes can constrict water flow and result in less water for downstream hydropower plants. Heavy ice can delay the opening of the shipping season and be a hazard to navigation, but it also can lead to higher water levels, allowing ships to carry more cargo.

Given ice’s environmental and economic importance to the Great Lakes region, scientists have good reason to continue studying it. In the future, Leshkevich plans to study ice cover thickness, and Austin is interested in developing numerical models that better explain ice’s connections to other phenomena. Wang is currently working on a model for forecasting ice cover.

Jennifer Yauck is a science writer at the UWM Great Lakes WATER Institute. GLWI (glwi.uwm.edu) is the largest academic freshwater research facility on the Great Lakes.

Forms of Great Lake Ice

• Pancake ice - circular, flat pieces of ice with turned-up edges that are shaped by wind- and wave-driven collisions with one another
• Brash ice - angular pieces of broken ice often piled on each other by wind and waves
• Lake/black ice - clear ice that looks dark when viewed from an aircraft or satellite
• Snow ice - milky white ice containing many bubbles, formed from water-soaked snow
• Frazil ice - fine spicules or plates of ice suspended in the water, formed during the first stage of freezing
• Source: George Leshkevich

The incredible, indelible cormorant

Along with the ducks, geese, and gulls that frequent the waters of Milwaukee is a bird that may be less familiar to most landlubbers: the cormorant.

A relative of the pelican, these large, black waterbirds can often be spotted perched on harbor breakwalls or in other places near Lake Michigan during the summer months. They are skilled fishers that use their webbed feet and streamlined bodies to dive underwater-often to depths of 25 feet, and sometimes more-in pursuit of a meal. “They’re just as agile underwater as penguins,” said Ken Stromborg, a retired U.S. Fish and Wildlife Service biologist who has studied cormorants for nearly 25 years.  »Read more

Turning Great Lakes wind into energy

Late this summer, Denmark inaugurated the world’s largest offshore wind farm, Horns Rev 2. Located nearly 20 miles from shore in the North Sea, the 209-megawatt wind farm consists of 91 turbines that together will generate enough energy for 200,000 households a year.

Closer to home, amid a growing interest in shifting from nonrenewable to renewable energy sources, the Great Lakes are attracting attention of their own as potential sources of wind energy. Ohio is currently working toward developing a pilot wind project in Lake Erie, while Ontario, Canada is seeking to develop projects in both Lake Erie and Lake Ontario. Meanwhile, Wisconsin is beginning to look more seriously at Lake Michigan’s wind-energy potential as the state works to meet its legislated goal of producing 10 percent of its electricity from renewable sources by 2015.

But while offshore wind as an energy source has advantages-it’s cleaner and consumes much less water than fossil fuel sources, and has the potential to produce more energy than land-based wind-it also will require addressing various environmental, technical, economic, and legal issues.

“[Great Lakes offshore wind] is an idea that’s worth considering. It has pluses and minuses-and agencies, industries, power producers, and customers will have to figure out if it can be done with more pluses than minuses,” said Steven Ugoretz, an environmental analysis and review specialist with the Wisconsin Department of Natural Resources (DNR). Ugoretz also served on a workgroup that produced a report earlier this year for the Public Service Commission (PSC) on the feasibility of offshore wind in Wisconsin.

Spawning Grounds

When it comes to aquatic resources, one of the top concerns related to Great Lakes wind energy is how wind farms might impact fish and fish habitat. Thus far, wind farms have been built only in marine environments, so solid information on how freshwater fish might interact with wind facilities is largely lacking. “It’s a big question mark,” said Jill Utrup, a biologist with the U.S. Fish and Wildlife Service (USFWS).

However, experts have identified a number of factors they think will be important to consider as potential wind farm locations are evaluated. One of those, according to the PSC report and a recent report from the Great Lakes Wind Collaborative (GLWC), is whether the site is a critical spawning area. Lake Michigan’s mid-lake reef, for example, has site potential from an engineering perspective, but it is also an important spawning ground for lake trout, a fish the DNR and USFWS are working to restore.

“It’s probably not a good idea to put these things where the trout are spawning, simply because we don’t know what the impacts would be,” said John Janssen, a scientist at UW-Milwaukee’s Great Lakes WATER Institute (GLWI) who studies the mid-lake reef. “We also don’t know what else might be spawning [at the mid-lake reef],” he said. “When we go over the reef with sonar, it seems to be a busy place, but we don’t know what it’s busy with.”

Utrup said that conducting surveys to identify important fish habitats can help minimize adverse impacts from wind farms. Surveys of breeding habits for birds and bats have proven useful for land-based wind projects, she said.

In areas without spawning habitats, wind farms would likely have less potential to adversely impact fish. In fact, wind farm structures might serve as spawning habitats in such areas and therefore actually have a positive impact, according to the PSC report.

Other Aquatic Issues

Another aquatic concern related to wind farms, cited in the GLWC report, is the potential for scouring of the lakebed by currents flowing around wind-turbine foundations. Scour could be beneficial or detrimental, said Janssen. It might expose more rock, thereby providing more spawning habitat for fish like perch, he said. Or, the exposed rock might act as an “attractive nuisance”-meaning fish might be drawn to spawn there, only to have their egg masses broken up by currents.

Other factors that could adversely affect fish-and therefore should be minimized or avoided-include noise and vibration from wind farm construction and operation, and the re-suspension of contaminated sediments during construction, according to the PSC and GLWC reports. Additional impacts that are harder to anticipate and detect in water than on land could also occur, cautioned Janssen.

On the plus side, wind farms could serve double duty as monitoring stations that would help scientists track fish and collect lake data, said Val Klump, GLWI director and scientist. “If we build these, we should build a monitoring network into them,” he said.

Overall, said Klump, “while offshore wind poses a number of technical and environmental challenges-like locating the structures to avoid habitat and ecological disruption-it also avoids some of the problems faced on land and has some real advantages. Given our increasing demand for energy, it’s definitely something we should be investigating.”

Jennifer Yauck is a science writer at the UWM Great Lakes WATER Institute. GLWI (glwi.uwm.edu) is the largest academic freshwater research facility on the Great Lakes.

• View the PSC report: psc.wi.gov/globalWarming/05EI144/index-WindonWater.htm.
• View the GLWC report: glc.org/energy/wind/pdf/Siting-Principles-and-Guidelines-for-Wind-Development-on-the-Great-Lakes_FINAL.pdf.

Oak Creek Power Plant artificial reef

For the past two summers, Great Lakes WATER Institute scientist John Janssen has been keeping an eye out for yellow perch and lake trout at a Lake Michigan reef two miles east of Oak Creek.

The reef is one of many along the lake’s primarily rocky-bottomed western side, but it has one characteristic that distinguishes it from most others. It’s artificial.

We Energies built the reef two years ago as part of a project to expand its Oak Creek Power Plant. The U.S. Army Corps of Engineers required the reef as mitigation for habitat that could be lost when the utility constructed new lakebed structures, including a coal dock extension and water intake and discharge structures, said David Lee, We Energies’ water quality manager.

The intent is for the reef to become a spawning ground for perch and trout. Janssen is monitoring the reef as part of a five-year assessment study, required by the Army Corps and funded by We Energies, to determine if it is meeting that goal.

People have been building artificial reefs since at least the 1700s, when the Japanese placed bamboo structures underwater to attract fish for commercial harvest. Today, reefs are also built to provide habitat for aquatic animals and plants, to attract fish for angling, and as destinations for divers.

Artificial reefs have been built in both ocean and freshwater environments, with everything from logs and rocks to scuttled ships and New York City subway cars serving as building materials. Several reefs in Lake Erie, near Cleveland, Ohio, are made of rubble from the old Cleveland Browns stadium.

The Oak Creek reef, which is actually a cluster of six parallel reefs, is made of roughly 31,000 tons of quarried Wisconsin limestone, said Lee. The Edward E. Gillen Co., which specializes in marine construction, built the structures. We Energies did not disclose the project cost. Each reef measures about 600 feet long, 100 feet wide, and between 10 and 15 feet high. They are designed somewhat “like Twinkies,” said Janssen, with an inner core of three- to five-inch stones surrounded on the top and sides by a layer of 10- to 30-inch armor stones. The reef complex lies in about 50 feet of water.

Fisheries experts from several organizations, including the Army Corps, U.S. Fish and Wildlife Service, Great Lakes Fishery Commission, Wisconsin Department of Natural Resources, and WATER Institute, worked collaboratively on the reef design.

Developing the design required some educated guesswork-based largely on knowledge of natural habitats-because little precedent for building a spawning reef in Lake Michigan exists, said Janssen. The Great Lakes have relatively few artificial reefs, and the best studied of these-reefs constructed in Lake Erie’s central basin in the late 1980s and in Lake Michigan near Chicago in 1999-were built expressly to attract sport fish and promote angling.

Evidence of Perch Spawning

To evaluate the Oak Creek reef, Janssen and UW-Milwaukee graduate student Chris Houghton visit it several times each summer, looking for evidence of spawning and counting the number and types of fish they see during dives and catch by net. For comparison, they are also studying an adjacent sandy site, and the natural Green Can Reef to the north.

This year in early June, which is when perch spawn, they found perch eggs for the first time at the Oak Creek reef. They didn’t find trout eggs there last year, but hope to find some this year during trout spawning season in October or November.

They’ve spotted a variety of fish at the reef, including lake trout, alewife, longnose suckers, and smelt, but the most numerous fish have been yellow perch and round gobies. But, said Janssen, “right now it’s not at a density that will be a bonanza for fishing.”

The researchers are also inventorying the plants and small, invertebrate animals that attach to the reef rocks. The tiny animals provide food for young fish.

“That’s one of the primary things we want to compare with Green Can-do we get the same kinds of bugs, and do we get as many?” said Janssen. “There are rocks that have been out there two summers now and they don’t look anything like Green Can. They don’t have nearly as much algae on them, which is food for the invertebrates. So it’s still developing.”

But overall, said Janssen, the young reef so far looks promising. “In that fish are around there now and perch are showing up already, that’s a good sign. But if it’s going to be spectacular, it’s going to need a few years to develop,” he said. “This isn’t going to be instantaneous. It’s not just rocks-it’s the whole community that has to develop.”

Jennifer Yauck is a science writer at the Great Lakes WATER Institute. GLWI (glwi.uwm.edu) is the largest academic freshwater research facility on the Great Lakes.

A Tricky Issue

Artificial reefs are often thought of as a way to give new life to old ships, subway cars, and other materials while boosting fish populations and increasing opportunities for recreational fishing and diving. But artificial reefs can have downsides, too. Some scientists and environmentalists worry that artificial reef initiatives may be turning some coastal areas into underwater junkyards. There’s also debate over whether artificial reefs actually help produce more fish, or simply attract existing fish populations, thereby concentrating them and making them more susceptible to overfishing. Some ways people try to minimize the potential negatives of reef building are through careful planning, follow-up monitoring and assessment, and restrictions on fishing.

A day in the life of the Neeskay

SPECIAL REPORT, JUST FOR KIDS!

“One long blast! Cover your ears!” shouted Captain Greg Stamatelakys, sounding the Neeskay’s horn and steering the 71-foot research boat from its dock at the Great Lakes WATER Institute (GLWI) into the Kinnickinnic River. It was a sunny August morning in Milwaukee, just past 9:15am according to the nearby Allen-Bradley clock. The Neeskay, painted black with a diagonal yellow stripe across its bow, was heading out for another day of research on Lake Michigan.

The cruise’s main mission: collect data and samples at a site 12 miles northeast of Fox Point, Wis. Like most research on the water, this cruise required the help of many hands. Scientists Carmen Aguilar and Russell Cuhel led the day’s research activities. Tyler, a technician, and Jeremy, a student intern, assisted them. Geoff, an engineer, and Jim, a deckhand, were along to help the captain with boat duties.

Underway

The group had prepared for the trip earlier in the morning, loading gear and groceries onto the boat. As the cruise got underway, they talked about the weather and the day’s plan, and labeled the empty bottles and vials that water samples would go into later.

Just after departing, the Neeskay made two quick stops near the Hoan Bridge, where Milwaukee’s major rivers meet and flow into Lake Michigan. There, the researchers used a bucket to grab water samples for scientist Sandra McLellan, who stayed behind to collect additional samples at area beaches. Later, McLellan would check all the samples for bacteria washed in by the rainfall of the past three days.

The boat then followed the Lake Michigan shoreline north, stopping at several other sites to collect more water samples for McLellan. Along the way, the Neeskay passed two research buoys its crew had deployed from the boat’s stern earlier in the year. Bobbing in the blue-green water at sites off Bradford and Atwater beaches, the buoys continuously transmit weather and water data by radio back to scientists at GLWI, helping them study long-term lake trends.

Back in the pilothouse, Captain Greg next pointed the Neeskay toward the day’s main destination, the Fox Point site. This is one of several sites Carmen and Russell regularly visit to study how the lake’s physical and chemical properties affect plankton, the tiny plants and animals that support the lake’s food web. Cruising at 11 miles an hour, the ship took over an hour to get to there. In the meantime, everyone took turns grabbing lunch in the galley below deck.

Though small, the galley contains all the kitchen essentials: a sink, a refrigerator and microwave, a table and chairs. It also contains bunk beds where crew members can sleep during overnight cruises. Beyond the galley, in the Neeskay’s bow, are two more sets of bunks and a tiny bathroom. These spaces once held Army cargo: built in 1953, the boat served as an Army T-boat before being converted for research use.

Arrival

“On station!” yelled Captain Greg when the Neeskay finally reached the Fox Point site. As Geoff dropped the anchor into the 105-meter-deep (345 feet) water, all hands gathered on deck, ready for more work.

One of the first tasks was to measure the water’s clarity. Leaning over the boat’s side, Carmen lowered a device called a Secchi disk into the water by hand until she could no longer see it. “Eighteen meters,” she said, announcing the depth (59 feet) at which the black-and-white disk disappeared and recording it in her notebook.

Meanwhile, Russell and Jeremy worked to collect water samples from various lake depths. The two took turns climbing out onto the hero platform protruding from the Neeskay’s starboard side and attaching Niskin bottles to a cable. Using a winch, Jim then lowered and raised the bottles on the researcher’s signals. Tyler helped transfer the collected water into storage jugs.

The group also used the hero platform and winch cable to deploy nets to collect plankton, sensors to record water quality data, and metal PONAR jaws to scoop mud and organisms from the lake bottom. They took other measurements at the site, too-of things like temperature and light penetration-with hand-held equipment lowered over the boat’s side.

On some cruises, Carmen and Russell also deploy a remotely operated vehicle (ROV) from the stern of the Neeskay. Outfitted with a camera, the ROV can collect samples and film underwater video. On other Neeskay cruises, divers manually collect samples or perform maintenance on equipment such as buoys.

Several hours after arriving, the group had completed its work at Fox Point. “Milwaukee Harbor, north!” Russell shouted up to the captain, who began steering the Neeskay back inland to make a few more quick stops to collect additional data.

During the return trip, the researchers cleaned and packed their gear, and began processing some of their water samples in the boat’s lab, squeezing them through filter paper to remove particles and tiny organisms. Eventually, they took seats on the deck and watched the city skyline come closer on the horizon.

The hands of the Allen-Bradley clock showed 6pm as the Neeskay docked at GLWI and everyone helped unload the boat. Back at their lab, Carmen and Russell worked into the evening analyzing their samples. Over the next week, their staff helped them complete more analyses. Meanwhile, the Neeskay headed out for more scientific missions on the water.

Jennifer Yauck is a science writer at the Great Lakes WATER Institute. GLWI (glwi.uwm.edu) is the largest academic freshwater research facility on the Great Lakes. Teachers can contact her at yauck@uwm.edu.

Glossary

• Bow - front of boat
• Cruise - an outing by boat
• Food web - the feeding relationships between organisms in an ecosystem
• Galley - boat’s kitchen
• Hands - crew members
• Hero platform - platform protruding from the side of the boat, so named because work performed there can be perilous
• Niskin bottle - a tube-like bottle with two open ends that snap shut at a desired depth, trapping water inside
• PONAR - sampling device named for the five people who invented it: Charles Powers, Robert Ogle, Jr., Vincent Noble, John Ayers, and Andrew Robertson
• Port - left side of boat (when facing forward)
• ROV - remotely operated vehicle
• Secchi disk - a disk used to measure water clarity by noting the greatest depth at which it can be seen
• Starboard - right side of boat (when facing forward)
• Stern - back of boat
• T-boat - small army boat that transfers cargo from larger ships to shore

Additional Photos

Click here to view a slideshow that includes nearly 40 photographs. While viewing the slideshow, you may click on a photo to read it’s corresponding caption.

Reclaiming the Kinnickinnic River

When workers hoisted a large clamshell bucket filled with sediment from the bottom of the Kinnickinnic River earlier this summer, it was a sign that the river’s fortunes had begun to change.

The bucketful was the first of many in an ongoing project aimed at removing pollutants and deepening the river over a 2,000-foot-long stretch near Bay View’s northern edge, between Becher Street and Kinnickinnic Avenue. The U.S. Environmental Protection Agency (EPA) and the Wisconsin Department of Natural Resources (DNR) are overseeing the $22 million dredging project, which is funded by federal and state dollars.

“It’s the first major investment in the river to take place in some time,” said Ben Gramling, director of environmental health programs at the Sixteenth Street Community Health Center (SSCHC). SSCHC is involved in efforts to improve the Kinnickinnic River, which runs through neighborhoods the center serves. »Read more

Mercury still subtly hazardous

In the 1950s, the Japanese fishing village of Minamata was hit by an inexplicable outbreak of health problems-from vision loss and paralysis in adults to physical deformities and cerebral palsy in newborn babies.

The cause of the villagers’ mysterious symptoms was eventually traced to mercury poisoning. The villagers had unknowingly received exceptionally high doses of mercury through fish they ate from Minamata Bay, where a chemical plant had been dumping the pollutant for years. The experience revealed for the first time that mercury can move up the food chain to people.  »Read more

Flood of ‘08 served up feast for fish

One year ago this month, a series of severe storms moving across the Midwest dropped nearly a foot of rain on the Milwaukee area in just 10 days. The deluge caused widespread flooding that damaged homes and businesses, washed out roads, closed the airport, and belched plumes of sediment, debris, and sewage into Lake Michigan.

But the flood may also have delivered food to some of Lake Michigan’s fish when they needed it most.

Among the many things the area’s swollen rivers carried out to Lake Michigan during and after the storms was a mix of the rivers’ microscopic algae (phytoplankton), including diatoms, said Carmen Aguilar, a scientist at the Great Lakes WATER Institute. Diatoms are one of the largest forms of phytoplankton and the only form having glass-like cell walls made of silica. Diatoms also are packed with lipids, making them a nutritious meal for newly hatched fish and the tiny aquatic animals that newly hatched fish also eat.  »Read more

Little quagga mussel has big impact on Lake Michigan

In his  lab at the Great Lakes WATER Institute, scientist Russell Cuhel places several quagga mussels into a beaker containing water tinted green with tiny algae. Within a half hour, the hungry mussels suck up virtually all the algae in the beaker, leaving the water clear.

 A similar scene plays out year-round on a much larger scale in Lake Michigan, where trillions of the invasive mussels have colonized rocky and sandy areas of the lakebed since the species’ arrival less than a decade ago. These filter feeders’ voracious appetites have transformed vast areas of the lake from cloudy to Caribbean clear. That may be a boon for divers and others who benefit from greater visibility in the water. But to scientists like Cuhel, it’s a symptom of a dramatic shift in the lake’s food web.  »Read more

What does the Great Lakes Compact mean for water conservation?

Seven years in the making, the Great Lakes Compact went into effect last December after successfully passing through the legislatures of the eight Great Lakes states and Congress. This historic, multistate agreement outlines a regional approach for sustainably managing the waters of the Great Lakes.

A central component of the compact is its ban-with limited exceptions-on diversions of Great Lakes water to points outside the Great Lakes basin, an area defined by the lakes and land that drains into them. This piece of the compact has received considerable attention, particularly in Wisconsin, where the city of Waukesha is on track to become the region’s first out-of-basin community to apply for an exception to the diversion ban.

The Great Lakes Compact bans diversions of Great Lakes water to points outside the Great Lakes basin, with limited exceptions, and requires the use of conservation programs within the basin. The Great Lakes basin is defined by the five lakes and land that drains into them. Eight states and two Canadian provinces have land in the basin. ~courtesy Great Lakes Commission

Perhaps equally significant but less discussed is a compact component that requires the Great Lakes states to implement water conservation programs in areas within the basin. In Wisconsin, Governor Jim Doyle wants to go even further: he has called for a conservation program for the entire state.

“Many communities that rely on groundwater are already reaching the limits of their water supply, and finding additional water sources will be expensive,” said Jeff Ripp, water conservation coordinator at the Public Service Commission of Wisconsin (PSC). “Conservation is the cheapest source of new water.”

Wisconsin’s Conservation Program

Under the compact, each state designs its own in-basin conservation program and decides if the program will be voluntary or mandatory. However, the program’s objectives must be consistent with agreed-upon regional objectives. The states have until December 2010 to develop their objectives and implement their programs. Wisconsin served as a pilot case and already finalized its objectives last December (see sidebar). The Wisconsin Department of Natural Resources (DNR), Wisconsin Department of Commerce, and PSC were in charge of the development process.

Next, the DNR must write the rules detailing the nuts and bolts of how the program will work. The agency must submit a draft to the state Legislature by December 2009.

Todd Ambs, DNR’s Water Division administrator, said Wisconsin is moving toward using a tiered program of increasingly rigorous conservation requirements-ranging from voluntary to mandatory-for water users (water utilities, industries, agricultural operations, etc.). Users will be ranked based on their location and water use-for example, small, out-of-basin users will be in a less rigorous tier than highly consumptive in-basin users or out-of-basin users with approved diversions.

The program’s most rigorous mandatory requirements will be enforced through a permitting process. Water users will need to obtain a permit for new or increased in-basin withdrawals averaging 100,000 or more gallons of water per day over 30 days, and in the process demonstrate they are meeting the program’s conservation requirements. Large-scale industrial or irrigation operations and water utilities serving more than 1,000 customers are among the types of users with this level of water usage.

The city of Milwaukee’s water utility and other in-basin users that existed as of the compact’s effective date and surpass the 100,000-gallon threshold also will need a permit, but their existing use and capacity will be grandfathered in, said Ambs. However, these users would still be subject to any mandatory requirements deemed necessary in the future as the cumulative impacts of withdrawals and diversions around the basin are assessed, or if they want to expand their existing capacity.

Users with approved diversions will need to demonstrate they are returning all water back to the basin, said Ambs.

The DNR is still developing the specific quantitative standards upon which the program’s conservation requirements will be based.

 

  
Domestic includes indoor and outdoor household uses such as drinking, bathing, flushing toilets, and lawn watering. Agriculture — non-irrigation includes water used for livestock and aquaculture. Public use and loss includes, among other things, water used in public parks or for fire control, and water lost from water main breaks and distribution systems. Although thermoelectric power generation uses the most water in Wisconsin, little of this water is consumed, meaning most of it is returned to the natural system after use. (Water for thermoelectric power is used in generating electricity with steam-driven turbine generators, according to the USGS, and one of the main uses of water in the power industry is to cool the power-producing equipment.) The water use in Wisconsin with the highest rate of consumption is agriculture. See wi.water.usgs.gov/data/wateruse.html#reports for more information. Source: U.S. Geological Survey data

The Look of Conservation

So what might water conservation look like for Wisconsin users? “It’s not one-size-fits-all,” said Ripp. “There are many types of users, so to be very effective, it has to be locally driven.”

Water utilities in some communities, for example, could choose to implement conservation rate structures for residential water use, said Ripp. Under such structures, a water utility could charge you a few cents more per 1,000 gallons if you use more than a to-be-determined volume of water over a given period. The idea is the more you use, the higher the rate. Many utilities today use a rate structure that is just the opposite, with rates decreasing as water use increases. “Out West they’ve been using [conservation] rate structures for years,” said Ripp.

For agricultural and industrial users, “best management practices” or BMPs likely will be important, said Eric Ebersberger, DNR’s Water Use Section chief. BMPs include things like using efficient irrigation techniques or reusing water within manufacturing processes. Ebersberger said that by reducing water use, large-scale operations also reduce their energy use-and boost their savings. “It costs a lot of money to pump water,” he said.

Both Ebersberger and Ambs said that conserving now gives the region an opportunity to avoid a water crisis later. “The good news about this part of the country is that we can sustainably manage the Great Lakes. We feel confident we can do that in a way that provides water for environmental protection and economic development,” said Ambs. “We don’t have to face the difficult choices that places like Arizona, Colorado, and California have to face.”

Jennifer Yauck is a science writer at the Great Lakes WATER Institute. GLWI (glwi.uwm.edu) is the largest academic freshwater research facility on the Great Lakes.

Look to future issues of the Compass for more following the Waukesha diversions issue.

In 2007…

The average residential household in Wisconsin used about 160 gallons of water per day.

The Milwaukee Water Works pumped an average of 114,719,699 gallons of water per day.

The Cudahy Water Utility pumped an average of 3,974,121 gallons of water per day.

The Soldiers Grove Municipal Water Utility pumped an average of 46,071 gallons of water per day.

Source: Public Service Commission data

WISCONSIN’S CONSERVATION OBJECTIVES

1) Improve monitoring and standardize data reporting among state and provincial water conservation and efficiency programs.

2) Adopt and implement supply and demand management to promote efficient use and conservation of water resources.

3) Guide programs toward long-term sustainable water use.

4) Develop education programs and information sharing for all water users.

5) Develop science, technology, and research.

Bringing aquaculture to Milwaukee

Jon Bales and Leon Todd have a vision for Milwaukee’s future, and it involves fish.

The two retirees believe Milwaukee has an opportunity to become a national leader in the emerging industry of urban aquaculture, and they hope the organization they cofounded, the Urban Aquaculture Center (UAC), will provide a jump-start.

Aquaculture, like agriculture, is the cultivation of plants and animals, but it is done in water rather than on or in soil. Fish, shellfish, and aquatic plants such as seaweed all can be raised using aquaculture techniques.

Historically, aquaculture has mostly been practiced away from large population centers-in manmade ponds, cordoned-off sections of rivers, or open-water cages. But now a movement is underway to bring an indoor brand of aquaculture to urban areas, spurred on by an increasing demand for locally produced food, a substantial U.S. seafood trade deficit, and concerns over food security.  »Read more

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