Status Elsewhere

From August 8, 1990 (update #3)

Three zebra mussels sightings in July confirm that the mollusk has established a foothold in Lake Michigan:

BRIDGEMAN, Mich. - In mid-July, divers found about 100 zebra mussels in and around the water system of the Donald C. Cook Nuclear Power Plant near Bridgeman, according to Alan Gaulke, senior biologist with the American Electric Power Service Corp. Gaulke said divers found zebra mussels on walls of the plant's water intake forebay during routine maintenance on July 18, and they found a few others within the plant's circulating water tunnels and on rip-rap surrounding the intake structure. The Cook plant already treats water systems with chlorine to control fouling from microorganisms, Gaulke said. Company officials have asked the Michigan Department of Natural Resources to approve an increase in the chlorination treatments to kill adult zebra mussels within the plant's water system and to kill veligers that may enter the system and attempt to establish themselves. Gaulke said the plant has monitored its water system for Asiatic clams since the early 1980s, and it notified its employees to watch for signs of zebra mussels after the mollusk showed up in Lake Erie. "Anytime they're doing routine work, the people under water or the people pulling pipe systems apart inspect everything for the presence of any mollusk," Gaulke said. "All of our divers are notified when they come on-site to be on the lookout for mussels and Asiatic clams." Asiatic clams are another exotic nuisance mollusk that is causing problems in warmer southern parts of the U.S. but is a lesser concern here than zebra mussels because it doesn't attach to objects and doesn't reproduce well in cold waters like Lake Michigan.

EAST CHICAGO, Ind. - On July 17, Ron Clark, a commercial diver contracted by the Inland Steel Company, found 15-20 zebra mussels attached to a concrete wall near the intake for the company's No. 7 water pumping station. The mussels were all less than an inch long. The Inland Steel facility is on an artificial peninsula that extends into Lake Michigan.

GARY, Ind. - On July 9, maintenance divers found several zebra mussels in the water intake of the Union Carbide Industrial Gases plant in Gary. Dave Zieba, plant engineer, said the divers were cleaning trash screens inside the forebay of the water intake when they found the mussels attached to Asiatic clams. On July 13, divers examined the plant's 84-inch intake pipe and found more zebra mussels - about four per square foot at the beginning of the 2,000-foot- long intake pipe, and about one per square foot where the pipe meets the forebay, Zieba said. "They're definitely not a problem yet," the plant engineer said, "but they are there.".

ID: 19900808-3.

The Zebra Mussel Update was a 4- to 8-page quarterly national newsletter published by the University of Wisconsin Sea Grant Institute from May 1990 through May 1997. The ZMU documented the spread of the zebra mussel -- an exotic nuisance mussel -- through North America's freshwater environments, especially the Great Lakes, and on efforts to control it.