News Update

POSTED: Tuesday, Aug. 25, 2009

‘Just like rust,’ invasive mussels ready to invade Northwest

Environment: Species a threat to state’s ecosystem

WASHINGTON – Highly invasive mussels are lurking on the Northwest’s doorstep, threatening to gum up the dams that produce the region’s cheap electricity, clog drinking water and irrigation systems, jeopardize entire aquatic ecosystems and upset efforts to revive such endangered species as salmon.

And despite ongoing efforts to stop them, the arrival of zebra and quagga mussels might be inevitable.

Some scientists say the mussels could arrive within five years. Others say the mussels’ larvae already might be spreading undetected, though no one is sure whether they will survive or thrive in the Northwest’s rivers, streams and lakes.

“They are getting closer and closer,” said Jim Ruff of the Northwest Power and Conservation Council. “They are a huge concern.”

The mussels are among the fastest spreading invasive species to arrive in the United States. The invasion began in the late 1980s in the Great Lakes, probably arriving in the ballast water of freighters that had been in the Caspian Sea.

Originally from Eastern Europe and the Ukraine, the mussels have now been found in 22 states, including California, Nevada and Utah, and two Canadian provinces. They are in the Great Lakes, the Mississippi, Ohio, Cumberland, Hudson and a handful of other rivers. They also have infected the Colorado River system on which 27 million people rely for drinking and irrigation water, hydropower and recreation.

In May, a 26-foot boat on a trailer that had been on Lake Mead outside Las Vegas, on the Nevada-Arizona border, was stopped near Spokane. Its bottom was covered with the mussels.

“If someone offered to bet me they would be in the Northwest within five years, I’d take it,” said Stephen Phillips, a senior program manager with the Pacific States Marine Fisheries Commission, which was established by Washington, Oregon, California, Idaho and Alaska to support activities that conserve, manage and develop marine resources.

INVASIVE SPECIES

The mussels reproduce prodigiously. One study cited by the U.S. Geological Survey found that a single mussel can produce 1 million eggs a year.

The fertilized mussel larvae float through the water, feeding on tiny phytoplankton and beginning to grow. Juvenile mussels attach themselves to just about anything solid, including the hulls of boats and barges, which spread them even farther.

At one Michigan power plant, the mussels were found in densities of 700,000 for roughly every square yard and in layers a foot thick. According to the USGS, navigational buoys have sunk under their weight, and small mussels have been known to get into the engine cooling systems of boats.

“The history of these mussels is they keep moving into new territory,” said Fred Nibling Jr., of the Bureau of Reclamation’s Ecological Research and Investigations Group in Denver. Nibling recently briefed members of the Northwest Power and Conservation Council, which oversees the development of comprehensive plans to meet the region’s energy needs and restore salmon runs.

“They will become part of our life, just like rust,” Nibling said.

Power managers in the Northwest are especially concerned because the region has the most extensive hydroelectric system in the nation. Nearly half of the wholesale power sold in the Northwest is produced at the 31 federal dams operated by the Bureau of Reclamation and the U.S. Army Corps of Engineers, on the Columbia and Snake rivers and their tributaries.

The dams produce enough electricity to power 20 cities the size of Seattle. Among them is Grand Coulee Dam, which still ranks fifth in the world in terms of energy production. Grand Coulee also has made possible the Columbia Basin Irrigation Project, which has turned roughly 600,000 acres of Central Washington desert into some of the nation’s most productive agricultural land.

In addition, public and private utilities own and operate eight other major dams on the Columbia and Snake rivers. Dozens of smaller hydroelectric dams are found on rivers throughout the region.

Of all the things to which the invasive mussels like to attach, concrete may be top on the list. The dams are mostly made of concrete.

At Hoover and other dams on the Colorado River, officials fear the mussels could disrupt hydropower operations. They have clogged water intake and cooling systems for turbine bearings, compressors and transformers.

In the Northwest, dam operators are also concerned the mussels could clog fish ladders and other facilities that allow endangered salmon to bypass a dam’s spillways and turbines. The edges of the mussels are sharp, and fish ladders could become a hazard for salmon.

“They could slice and dice the salmon,” said Ruff of the Northwest Power and Conservation Council.

But that’s not the only problem.

The mussels filter microscopic organisms such as phytoplankton out of the water. An individual mussel can filter a quarter of a gallon of water a day. Some scientists believe the clearer water in eastern rivers and lakes is as much a result of the mussels filtering water as it is of environmental cleanup efforts.

The microscopic organisms are at the bottom of a complicated food chain and the invasive mussels could disturb it, affecting animals further up the chain.

“It’s a huge threat to the entire ecosystem of the Northwest if they get in here,” Ruff said.

COSTLY PROBLEM TO FIGHT

If the mussels do arrive in the Northwest, fixing the problem won’t be cheap or easy.

The U.S. Coast Guard has estimated that economic losses and mussel control efforts in states already infected is costing $5 billion a year. Initial estimates for fighting the mussels on the federal Columbia River dams are nearly $25 million, with additional annual maintenance costs.

Most of the efforts elsewhere have focused on painting with anti-fouling marine paint or using the small, slow release of diluted chlorine to kill the mussels. But because of the endangered salmon, steelhead and other species those approaches may be too toxic and would require federal permits in the Northwest.

Other possibilities being tested include using a natural bacteria, sound vibrations, ultraviolet light, electrical current, high-intensity water jets or hot water to kill the mussels. They can also be removed manually.

“They could create huge headaches,” said Ross Hendrick, a water quality specialist with the Grant County Public Utility District, which operates two dams on the Columbia River.

For now, officials are watching and waiting.

All four Northwestern states are checking recreational boats coming into the region on trailers, with special attention on those from Nevada or Arizona. Idaho has the most aggressive program, stopping and checking every boat coming into the state. Other states have launched similar efforts. California reportedly is using mussel-sniffing dogs.

Lakes, reservoirs and rivers throughout the region are being monitored and sampled. The Bureau of Reclamation is using money from the economic stimulus program to sample 60 lakes and reservoirs around the West, including Lake Roosevelt behind Grand Coulee Dam.

Most federal, state and local agencies are well aware of the problem, though the U.S. Army Corps of Engineers faces some criticism for taking the possible invasion too lightly and not asking for needed funding until 2011.

“They are being short-sighted,” Ruff said. “But they don’t even have enough money to maintain their projects.”

But corps officials say the possible mussel invasion is a priority.

Les Blumenthal: 202-383-0008

lblumenthal@mcclatchydc.com