Tag: hoover

Tiny Pest Threatens the Las Vegas Lights

  • Hoover Dam's backside stretches more than 700 feet from top to bottom, but the dam's seeing trouble from the tiny aquatic zebra mussel. (Photo by Shawn Allee)

Hoover Dam generates some of the power that lights Las Vegas all night long. But there’s something
that’s making that job a bit more difficult. Shawn Allee found out, it’s a tiny aquatic pest:

Transcript

Hoover Dam generates some of the power that lights Las Vegas all night long. But there’s something
that’s making that job a bit more difficult. Shawn Allee found out, it’s a tiny aquatic pest:

The usual tour of Hoover Dam starts at the visitor’s center – way at the top.

Robert Walsh works with the federal agency that runs Hoover.

He says, go ahead – look over the edge.

Allee: “OK. That’s creepy. Seriously, that’s creepy.”

Walsh: “It’s spooky. Are you afraid of heights?”

Allee: “No, they don’t bother me at all.”

The dam stretches down 700 feet, and it holds an enormous reservoir – Lake Mead.

This tour is awesome, but Walsh says there’s another tour, too.

It’s, um, NOT so awesome.

It’s all about the trouble the tiny quagga mussel is causing Hoover and other nearby dams.

To get that tour, Walsh takes me to Leonard Willet.

Allee: “Where are we right now?”

Willet: “It’s kind of a work station where all the quagga mussel control activities take place
for Hoover Dam.”

Allee: “It’s quagga mussel central for this area?”

Willet: “Exactly.”

Willet first heard quagga mussels were growing in the nearby Lake Mead reservoir in 2007.

He called an expert for advice.

“First thing out of her mouth was, ‘I’m sorry to hear that.’ I knew it was a lot more serious.
And I asked her what we’re in for.”

Willet learned quickly enough – quagga mussels attach to nearly anything underwater.

He shows me a sandal that was in water – and is smothered in them.

They’re like clams the size of your pinky fingernail.

“We went from zero to THAT in seven months.”

And that’s the problem.

Hoover Dam uses water from Lake Mead to spin generators.

The water moves around in pipes – and quagga mussels can attach to them – just like on that sandal.

Allee: “What does that mean in a real practical sense?”

Willet: “Our intake towers would close off. Once you start closing off, you can’t spin the
generators. That’s just kind of the big view of it.”

Zero power generation.

That’s the worst-case scenario. It hasn’t happened – but it’s a fight to prevent it.

“Now, we’re going to go down to the third floor, which is the generator floor.”

The generators are inside broad metal cylinders.

Big water pipes turn the generators. Smaller ones cool them off.

“Well, we circulate cold water from those pipes. If those start to plug up with mussels, then
you can’t keep a generator cool, if those … it shuts down due to overheating.”

Right now, it takes a lot of scraping to keep everything clear.

All this effort’s adding up – Willet says he’ll spend 2 million dollars soon on new equipment.

Even with that, Willet is still a bit jittery about some pipes outside, at the very bottom of the dam.

“The one that’s probably the scariest of all is, we have a fireline that runs around here.
Mussels love it. Then, your firelines, when they’re needed, are plugged with mussels. So
that’s another area you have to really be careful of, safety-wise.”

This didn’t have to happen.

Quagga mussels invaded eastern rivers and the Great Lakes first.

Experts figure the mussels hitched a ride West on someone’s fishing boat.

Apparently – someone didn’t clean their boat properly – and mussels dropped into Lake Mead.

Allee: “When they built this amazing structure during the Depression, do you think they had
any idea that something like this could ever happen?”

Willet: “I think there was a lot of disagreement among professionals that a little mussel the
size of your finger nail could impact a large hydro facility, but we’re quickly learning a bunch
of them can impact water and power delivery.”

Willet says if boaters aren’t careful – they’ll spread quagga mussels to the Pacific Northwest, where
there’re lots of dams and hydro power plants.

After all, if it can happen at mighty Hoover Dam – it could happen anywhere.

For The Environment Report, I’m Shawn Allee.

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Study: How Chronic Wasting Disease Is Spread

A new study finds that deer can spread a fatal brain wasting disease through saliva and blood. Rebecca Williams reports the researchers say this means no part of an infected animal should be considered safe to eat:

Transcript

A new study finds that deer can spread a fatal brain wasting disease through saliva and blood. Rebecca Williams reports the researchers say this means no part of an infected animal should be considered safe to eat:


Chronic wasting disease or CWD, affects deer, elk and moose, and it’s always fatal. CWD has been found in animals in 14 states and two Canadian provinces. Up until now, exactly how the disease spreads between animals has been a mystery.


Now a study in the journal Science shows evidence deer can spread CWD in their saliva and blood. Edward Hoover is the study’s lead author.


“No part of an infected animal is currently recommended to be consumed by people and these findings just underline that, that in addition to nervous system, the lymphoid system, we’d have to consider all parts certainly inappropriate for human consumption.”


Hoover says right now there’s no evidence people are susceptible to CWD, but he says scientists also can’t rule it out yet.


For the Environment Report, I’m Rebecca Williams.

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Ten Threats: Canals Past and Present

  • This is an ocean vessel in the Soo Locks, Sault Ste. Marie, Michigan. The Soo Locks connect Lake Superior and Lake Huron, allowing for ships to travel back and forth. (Photo courtesy of EPA)

One of the Ten Threats to the Great Lakes identified by experts across the region is the possible
expansion of canals to allow larger ocean-going ships into the lakes. Some see the expansion of
shipping channels as a threat to the environment; others see it as great economic opportunity.
Just like in the early days of settlement, they see the shipping channels on the Great Lakes as
a way to make trade opportunities better.

Transcript

In our next report from the series, “Ten Threats to the Great Lakes,”
Lester Graham brings us a look at shipping on the lakes. Some people think
bigger ships could bring more trade to the region:


One of the Ten Threats to the Great Lakes identified by experts across the region is the possible
expansion of canals to allow larger ocean-going ships into the lakes. Some see the expansion of
shipping channels as a threat to the environment; others see it as great economic opportunity.
Just like in the early days of settlement, they see the shipping channels on the Great Lakes as
a way to make trade opportunities better.


Native Americans had canoe trade routes on the Great Lakes long before the Europeans appeared
on the scene. When French fur traders arrived, they copied what they saw. They built birch-bark
canoes to travel the lakes and to haul back fur pelts.


(Sound of Saginaw Voyageurs paddling and singing “Alouette, gentile Alouette…”)


Chuck Hoover is with the Saginaw Voyageurs, a group of re-enactors who re-trace the French
Voyageurs routes. Hoover says the large canoes were great until you ran into rapids on the rivers
connecting the lakes.


“What you had to do was pick up everything, including the boat, and carry it across the dry land to
the next place that you could put in water that was navigable.”


Those portages could be as long as seven miles. Carrying a canoe big enough to haul more than a
dozen men and the heavy bundles of fur pelts was a tough job and it slowed trade. So, some small
canals were dug to make passage easier. As the region developed even more valuable natural
resources were discovered. Bigger canals were needed.


Stanley Jacek is an Area Engineer with the U.S. Army Corps of Engineers at the canal and locks
at Sault Ste. Marie, Michigan. He says by the middle of the 1800s mining around Lake Superior
had become big business.


“Back in those days they discovered iron ore and copper in the upper end of the lakes here. So,
they had to get all that commerce down to the heartland of the country, so locks had to be
built.”


With a canal and locks to help ships negotiate the drop from one lake level to the next, the ore
could be transported to the big steel mills in industrial cities such as Cleveland and Gary, Indiana.


Christopher Gilchrist is with the Great Lakes Historical Society. He says you can’t underestimate
the value of those canals.


“The water-borne transportation was critical for the creation of the industrial age in U.S. history.
There’s a reason why the steel mills are located right on the banks of these Great Lakes. All the major
steel mills were located right by the water so that they could get their raw materials cost
effectively.”


At the other end of the Great Lakes the St. Lawrence Seaway opened in the 1950s to make it
possible for ships on the Atlantic Ocean to enter the lakes, and another big canal and set of
several locks overcame another obstacle to shipping on the Great Lakes – The Niagara Falls.


The Welland canal allows ships to go around Niagara. Since it first opened in the 19th century the
Welland canal and its locks have been enlarged four times. Each time the Welland canal locks
and the St. Lawrence Seaway have been made wider and deeper, the shipping industry builds
bigger and bigger ships to the point that they literally just squeak through…


(Sound of ship squeaking against timbers)


…Often rubbing up against the timbers that act as bumpers on the locks’ concrete walls.


Throughout the history of the canals, there’s been pressure to make them bigger and bigger.
Many feel the amount of shipping through the canals is tied directly to the economic well being
of the nation. The more the canals can handle the better the economy.


(Sound of buzzing, roar of compressor)


Back at Sault Ste. Marie, the locks open to allow another big ship through.


Stanley Jacek, the engineer at the Soo Locks connecting Lakes Superior and Huron says the
economic impact is pretty easy to track.


“What we do here in the way of passing of commerce mimics what’s happening in the country. You
can actually see spikes in the economy by looking at our traffic here.”


But some say the canals could do more than just reflect the health of the economy. They could
spur the economy if even bigger ships could come into the lakes. The ships, the kind carrying
containers ready to be pulled by trucks or loaded on rail cars, could go directly to Great Lakes
ports instead of ports on the East or West coasts. More direct shipping might improve the
region’s economy.


But environmentalists are worried. They say bigger ships from all over the world might mean
more alien invasive species damaging the Great Lakes. The wider, deeper channels might
damage the environment along scenic rivers connecting the lakes, and some believe expanding
the channels will let too much water flow out of the lakes that could worsen the problem of lower
lake levels seen in recent years.


The plans for bigger ships are on hold for right now. But, given the history of the canals, many
believe expansion is only a matter of time.


For the GLRC, this is Lester Graham.

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