A multi-million dollar nightmare for water managers?

What is only the size of a dime but costs millions of dollars worth of problems? A zebra mussel, and we certainly don’t want to see one in Saskatchewan. Keeping them out is not going to be easy, if experience elsewhere in North America is any indication.

A multi-million dollar nightmare for water managers? Zebra mussels and a related species, the quagga mussel, are small fingernail-sized mussels native to the Caspian Sea region of Asia. They were first discovered in North America in Lake St. Clair near Detroit in 1988 and have now spread to parts of all the Great Lakes, the Mississippi River, and are showing up in inland lakes as well as in the Red River in North Dakota. Next stop? Could be Manitoba.

Zebra mussels clog water-intake systems of power plants and water treatment facilities, as well as irrigation systems, and the cooling systems of boat engines. As early as 2002, Ontario Power Generation estimated that, as a direct consequence of zebra mussels, its operating costs increased by between $500,000 and $1 million per year at its Darlington and Pickering nuclear stations, and for fossil fuel stations, about $150,000 per year at Nanticoke, $75,000 per year at Lambton, and $50,000 per year at Lakeview.

Coming soon to a river near you? NOT ! 

Shearwater Marine Services Ltd. and Shearwater River Cruises Ltd. in Saskatchewan became acutely aware of the threat of this species in the course of importing a large riverboat – The Prairie Lily – to its river cruise operation in Saskatoon. The vessel had been in service in Laughlin, Nevada on the Colorado River downstream of Lake Mead, where the lower Colorado River has been colonized by quagga – and more recently zebra – mussels since both species started showing up in North America.

After The Prairie Lily was pulled from the Colorado River, the hull and drive mechanisms were immediately – and thoroughly – pressure washed to remove any accessible encrustations of mussels. The lower deck, hull and machinery (including any parts of the vessel that could have mussels attached) started off the slow haul north a couple of days later, and was taken to a boatyard near the Arizona/Utah border where it was determined that – to ensure zero infestation of living mussels or their larvae – the vessel would need to be quarantined for 18 days, and then have all her piping, sea-water intakes and heat exchangers tested and if necessary, purged with high-pressure steam.

After the quarantine had been completed, The Prairie Lily began her journey north through Utah, Wyoming, Montana and into Canada, arriving at Saskatoon May 18th. “It was a tense and frustrating month,” says Shearwater’s Mike Steckhan. “On balance, though, we would not have had it any other way,” he continues. “Happily, the transport company (which specializes in moving large vessels all over the USA and beyond) cooperated at every level to make sure the job got done right.” Steckhan is well aware of the problems caused by the pesky little bivalves, having spent many months over several years dealing with Canadian Navy ships on the Great Lakes and along the St. Lawrence River where zebra mussels have gained a very solid foothold. He is also cognizent of the delicacies of inter-agency regulations and enforcement through his years of involvement with the Navy’s Port Security operations.

Why we don’t ever want to move a mussel… into Saskatchewan 

For starters, zebra mussels are a major fouler of industrial, municipal, and hydroelectric water intakes and outfalls. They cause a decline in water flow and plant efficiency. De-fouling of water intakes and other equipment infested with zebra mussels costs millions of dollars each year. These, and related, costs confronting publicly owned water treatment facilities and other water-intensive industries, would ultimately be passed on to homeowners and consumers.

But it gets worse. Zebra mussels have the potential to severely impact native mussels and many other native species by interfering with feeding, growth, respiration, and reproduction. They filter algae from the water, turning it clear. (Interestingly, scuba diving in the Great Lakes area has become a growing sport because you can now actually see in the water. Unfortunately, the absence of microscopic aquatic plant and animal life will cause many species to disappear as the ecosystem changes radically.) Through their filtering activity, zebra mussels take in hazardous compounds such as polychlorinated biphenyls (PCBs). Fish and waterfowl that eat the mussels carry those poisons into the food chain. And, this invader has the potential to spread across Canada through rivers and streams as well as by migrating wildlife and – as has been the case in the USA particularly – the transport of recreational boats and industrial equipment that has not been properly decontaminated when it moves from mussel-infested waters to an uncontaminated area.

The invasion of Lake St. Clair by the zebra mussel in 1988 annihilated 13 native species in that lake and caused the near extinction of 10 species in Western Lake Erie: one of the greatest reductions of biodiversity ever witnessed in North America. In a 30-kilometre stretch of the Rideau River, just 25 kilometres south of Parliament Hill, the density of these creatures increased from one animal per square metre to 383,000 per square metre in just three years, wiping out all native mussel species in the process.

For Shearwater River Cruises president Peter Kingsmill, gaining an understanding of the complexity of the issues and learning about preventative procedures has been a bit of a head-turner. Kingsmill, a recipient in 1992 of the Governor General of Canada’s Conservation Award, acknowledges that combatting invasive species like zebra mussels is a very different matter from trying to conserve native species like pelicans: “Of course, it’s all about conserving the ecosystem as we know it, here where we live. It’s pretty horrifying to consider the potential impact on our fish stocks, let alone everything else.” “Will we be successful, as a province and as a country, in keeping the zebras away from Western Canada forever?” Kingsmill muses. “Certainly I don’t know. Perhaps nobody does. Folks live with these things in Europe and in eastern Canada and the US, after all. However, even if we only measure the financial costs, every year we do manage to keep them away is one more year where the cost of clean-up and maintaining our water supply infrastructure doesn’t put added strain on our economy.”

A short webliography about zebra and quagga mussels:
http://nas.er.usgs.gov/taxgroup/mollusks
http://www.anstaskforce.gov/spoc/zebra_mussels.php
http://www.oag-bvg.gc.ca/internet/English/att_c20021004se01_e_12345.html
http://boating.ncf.ca/zebra.html

And… typing “zebra mussels” into Google Images will be rewarded with some incredible – and scary – pictures that demonstrate why this is one global visitor we could well do without.

Peter



/zebramussel/ http://www.anstaskforce.gov/spoc/zebra_mussels.php http://www.oag-bvg.gc.ca/internet/English/att_c20021004se01_e_12345.html http://boating.ncf.ca/zebra.html And… typing “zebra mussels” into Google Images will be rewarded with some incredible – and scary – pictures that demonstrate why this is one global visitor we could well do without.