Damming News From Washington State

Trax3001BBS writes "A 65-foot (20-meter) crack has been found in Wanapum Dam, one of the major dams along the Columbia River in southern Washington. Water levels are being lowered to both reduce water pressure and give the inspectors access to the area. 'Earlier this week, an engineer noticed a slight irregular "bowing" above the spillway gates near where cars can drive across the dam. When divers finally took a look under water they found a 2-inch-wide crack that stretched for 65 feet along the base of one of the dam's spillway piers.' The article goes on to say, 'Even if the dam doesn't fail, the significance of the damage is likely to require extensive repairs and that, too, could impact the entire Columbia River system. "All these dams coordinate to generate energy on a regional scope," Stedwick said. "If Wanapum is impacted, that has impacts on dams upstream as well as below." Upstream dams would be required to handle more water; there's only one lower dam (Priest Rapids). After that is the last free flowing section of the Columbia river. I've taken walks along that section, and I've seen it deviate (higher or lower) by amazing amount of water, so it can handle the changing flow rate. Making this situation more complex, a large group of people would like that particular dam removed, as well as the one above and below it (think of the fish!). On top of that, after the Priest Rapids dam (downstream from Wanapum Dam) is the Hanford Nuclear Reservation, once a site for Plutonium production. Either of these issues could generate a ton of attention. Personally, I'd like to give the engineer that noticed a slight irregular 'bowing' my congratulations."

Comments

WTF?

[Sharkyfour]

I know this is going to kill my karma, but WTF?? That is the most poorly written article I've ever seen on here and I'd wager that most would find it completely off-topic for the site. Combined with the new commenting system, and I think my days here are over. It's been a fun ride, but adios Slashdot.

Re:WTF?

[PPH]

That is the most poorly written article I've ever seen on here

Stand by ....

and I'd wager that most would find it completely off-topic for the site.

Why? It deals with engineering and technology. If it was a crack in a Shuttle SRB seal we'd be discussing it. It may not be cool and sexy like the latest s/w SNAFU, but infrastructure gobbles up a lot of money and its maintenance (or lack thereof) is a major issue in this country and others.

Re: WTF?

[Anonymous Coward]

Um, you know, geeks aren't just interested in the latest software abomination running on 200 incomprehensible layers of poorly documented features to run some game on a cell phone for about a week, you know?

Re: WTF?

[The Grim Reefer]

It's because the Republicans want us All to die. They killed my mother with a different dam so this is nothing out of the ordinary for Republicans.

Washington state mostly voted for a democrat in the last presidential election. Has a democrat for governor. Has six members who are democrat to four republican in the US house of representatives and both senators are democrats. Is 55 to 43 in favor of the democrats in the lower state house. And is 26 to 23 in favor of the dems in the state senate. But the republicans are responsible for this dam? If that's the case, the democrats in that state should all be shot for gross incompetence. Or perhaps the republicans used voodoo? I've heard they do eat their young, on occasion.

I'm sorry to hear about your mother. But if somehow the government was responsible, then you need to direct your ire toward both parties as there is no way only one party could have done this without the other at least knowing.

Most likely someone screwed up in the engineering, or something was wrong with a batch of concrete. Worst case, an inspector got paid to look the other way. Or missed something.

Re: WTF?

[xyzzyman]

Unless the damn was built after using 3d rendered models and ran through thousands of simulations then it isn't "tech". It took no math or science to build the Erie Canal, the Hoover Dam or the Panama Canal. In seriousness this is a better story on the site than a story about outstanding student loan debt. The engineering in projects like this and what it will take to fix it requires the same skills as people who design realistic game environments and physics simulators, etc. Many facets all come into play. Anyone who doesn't see this as "news for nerds" should probably go visit the Hoover Dam or tour an aircraft carrier.

Re: WTF?

[Daniel Dvorkin]

It took no math or science to build the Erie Canal, the Hoover Dam or the Panama Canal.

Unfortunately, I had to read the rest of your post three times to make sure you weren't seriously claiming this. It's amazing the number of self-proclaimed nerds who don't seem to understand that technology actually does predate computers.

Lower the river, obviously

[Applehu Akbar]

If there is only one dam below Wanapum, this will be easy. But don't miss an opportunity to throw in a totally irrelevant mention of the Hanford nuclear weapons complex - you know, that place that itself gets irrelevantly dragged into any discussion of commercial nuclear power.

Re:Lower the river, obviously

[QuasiEvil]

Hanford, for the most part, sits high above the Columbia. A few feet of rise in the Columbia would almost certainly change nothing in relation to stored radioactive sludge tanks. Any ground seepage that was going on yesterday will still go on tomorrow, but as a bonus, the additional flow will provide greater dilution... It's a total red herring in this discussion.

Re:Lower the river, obviously

[Jawnn]

If there is only one dam below Wanapum, this will be easy.

Not so much. The author of TFS is an idiot. He missed McNary, John Day, The Dalles, and Bonneville dams.

Re:Lower the river, obviously

[riverat1]

The interesting thing about the Hanford reach of the Columbia River is that it is one of the few free flowing sections of the river above Bonneville Dam. Because of the Hanford Reservation it is also undeveloped and as wild as any section of the river in the US. It is home to one of the healthiest runs of Chinook Salmon in the Columbia River system.

Re:Lower the river, obviously

[brausch]

Point: there are quite a few Columbia River dams downstream of Wanapum, not just one. There is only one below Wanapum and above the free-flowing stretch of the Columbia, but that is only about 60 miles or so. Then there are a few hundred more miles of river with several more dams.

Point: there are many buried reactor cores at Hanford. Hanford is large though, over 500 square miles, and they are not subject to flooding even if the dam was gone.

Biggest concern at the moment is the potential fluctuations in the cost of electricity.

Moisture inside the dam wall

[MichaelSmith]

I believe the biggest problem with cracked dam walls is that moisture gets into the interior of the wall and softens the material which is keeping it strong. Then the crack opens a little bit more, more water gets in and you have a nice exponential curve happening.

There was a rumour about this happening to the hume reservoir in Australia about 20 years ago.

Re:Moisture inside the dam wall

[wiredlogic]

Water doesn't "soften" concrete. H2O is molecularly bound into its structure and is a necessary part of maintaining the strength of concrete. Water invading earthen dams, on the other hand, is a more serious problem.

Re:Moisture inside the dam wall

[Charliemopps]

The steel is bathed in moisture for decades without weakening. Concrete hardens and is stronger under water. Water cracks concrete via the thaw freeze cycle. Water enters the void, freezes, expands, widens the void. But a 60 foot long crack suggests something shifted under the damn.

Re:Moisture inside the dam wall

[rhook]

I don't know about all dams but the Hoover Dam is not reinforced.

Re:Moisture inside the dam wall

[Solandri]

It has nothing to do with the moisture. It has to do with pressure. A dam represents a boundary layer between high pressure (behind the dam) and low pressure (air in front of the dam. An intact dam's structure distributes those stresses evenly throughout its structure, and transfers them into the mountains/hills at the sides of the dam. A crack shifts the stresses which would've been borne by the cracked section to the uncracked sections, and particularly at the corners of the cracks. The high stresses at the corners cause the crack to grow. Eventually the crack grows large enough that the stresses are more than the uncracked section can withstand, and the dam fails.

That's what the engineer noticed. The dam was bulging because the uncracked section was holding back so much more stress than its design load that it physically deformed. 65 feet is a damn big crack (no pun intended). That engineer deserves a ticker tape parade in his honor.

William Mulholland didn't take action

[kriston]

William Mulholland didn't take action when the St. Francis Dam performed similarly, and after his inspection, killed up to 600 people twelve hours after his inspection.

Re:William Mulholland didn't take action

[DerekLyons]

William Mulholland didn't take action when the St. Francis Dam performed similarly, and after his inspection, killed up to 600 people twelve hours after his inspection.

The situation is just a *bit* more complex than your soundbite would indicate - and any repairs made on the cracks he inspected on the 12th of March would almost certainly have been just re-arranging the deck chairs on the Titanic. It's almost certain that the foundation on the west end of the dam had already been fatally compromised and the cracks were a symptom of the impending failure rather than the cause.

Re:William Mulholland didn't take action

[DarwinSurvivor]

It's almost certain that the foundation on the west end of the dam had already been fatally compromised and the cracks were a symptom of the impending failure rather than the cause.

Could the same not be true in this case as well? Even if the dam is irreparably damaged, this will at least hopefully give enough warning to relieve the pressure or in the worst case scenario, evacuate the immediate down-stream area.

"Think of the Fish"

[Oysterville]

That last free-flowing stretch of the Columbia River that the OP mentions is also the last stretch of Columbia River that maintains spawning habitat. It also accounts for a very large portion of the salmon that return through the Columbia River estuary every year. If removing this dam would open up more spawning habitat, this would not be a bad thing.

RAF refuses comment

[Nimey]

Meanwhile, the RAF categorically denies that an Avro Lancaster was seen near the dam earlier that day.

Re:WTF

[PNutts]

Actually, "bring it on". Bonneville (one of the five dams below it) generates a considerable amount of power for my area. On the other hand, we'll need that water this summer if we don't get more snowpack in the mountains.

could've been huge. hydro failure killed 200,000

[raymorris]

I'm sure glad they caught it. China has a similar series of hydroelectric dams. A failure caused a domino effect and when the Banquai dam failed it killed 200,000 people. I know TFA says the failure of this one dam wouldn't kill that many people, but that assumes the sudden tidal-wave-like flood doesn't effect the downstream dams. A domino failure on the Columbia river would be a catastrophe.

O.M.G

[malakai]

This is the problem with Hydro power. This is why we should go 100% solar and not use electricity at night. We can't safely use Hydro, it's too dangerous, the pressure levels and engineering is too dangerous and a single mistake could kill an entire ecosystem.

Think of the children down river from this dam!

If you have any incandescent bulbs, _YOU'RE_ to blame as well.

-Francis Candlemaker

Re:O.M.G

[Solandri]

You joke, but the worst power generation-related accident in history was the failure of a series of hydroelectric dams. About 30x more deaths than estimated by the UN and WHO to have been caused by Chernobyl.

I don't mean to say coal and oil are safer - they kill far more when used as intended. But the fact that the fuel needs to be delivered to a combustion chamber means you can usually cut off the energy source, limiting the scope of a single accident. That's not the case with hydro - once the water gets moving, there's pretty much nothing anything man-made can do to stop it. All that energy is gonna be released. Likewise, nuclear rates high in risk because the energy density of the fuel is so high - a million times higher than petroleum. Solar and wind would appear to be low-risk, but that's an illusion generated by their low energy density. When you normalize for how many solar panels or wind turbines need to be installed and maintained to generate 1 GWh of electricity, they end up killing more people than nuclear.

Everything has risk. The question isn't how much risk there is per disaster. It's how much risk there is per unit of energy generated.

dams down river

[wildfish]

There are 5 dams down stream of wanapum, 1 above the free flowing hanford reach and 4 dams below that. River "operations" involve a complicated coordination of all the dams and reservoirs to provide adequate flow for fish and year-round power generation. It is an interesting engineering problem - hacking a river. There is also a computer angle here in that several data centers are located in Grant County (which owns the generation rights) to take advantage of the cheap reliable power. Presumably those data centers are watching this closely. Power rates for everyone in the county will rise if they have less power to sell or if they have to buy power from outside the county. The system is dependent upon storage for of moving water down stream the river is very interesting in that water flowing through one dam

Re:dams down river

[Anonymous Coward]

You're correct. This is an "issue" because it's standard BR procedure, and all federal entities must be notified for this. SOP...

This is not a major problem right now, as it could be solved pretty easily. However, 24 miles downstream is the Hanford area, which borders 520 sq. miles of variously polluted soil. A sudden breach of Wanapum could cause a breach of Priest Rapids dam (~10 miles away) and flood the Hanford area, which has small areas of high radioactive contamination, the likes of which are part of a $2 billion/yr effort to clean. This area is generally a plain, with high features (White Bluffs) as it moves towards the Reach, to move water towards Hanford. The breach could spread flooding into these areas, which the US DOE hasn't accurately modeled. The other problem is the Tri-Cities, only 15 miles further downstream. 250,000 people...Their water supply is in danger.

There is no likely danger of this happening.

I grew up worrying this same thing, if the Grand Coulee failed.

Re:Well fix the dam thing!

[xyzzyman]

All I see is Beavis asking, "Is this a God dam?"

Data centers

[gbnewby]

The data centers in Quincy are quite large. Microsoft has a major facility, which is undergoing expansion. So does Yahoo, Intuit, Dell, and Sabey. These are major components of the tax base for the town of Quincy and elsewhere in Grant County. The data centers are highly resilient to power loss, with on-site diesel generators, 24x7 staffing, and all the other protections you'd expect. But prolonged use of the generators, if it becomes necessary, could exceed the permitted run time and accompanying pollution the facilities are allowed. Most likely, power from the other dams the Grant County PUD operates (or elsewhere on the regional power grid) could be routed to the data centers.

There are some other huge electricity consumers in the county. It's the world headquarters of a company that makes photovoltaic components, and also several food processors (all those potatoes from eastern Washington gotta be processed and cooked!). Industrial users might be able to turn down their power usage if there is a regional shortage, but data centers tend to operate at fairly stable 24x7 consumption levels. Major companies like those listed above have redundant facilities, and can shunt processing to other centers if required.

Site selection for major electricity consumers, including data centers, is a fascinating topic. The State of Washington has had various tax incentives to help businesses to choose to build facilities there. Electricity costs are among the lowest in the nation (under 3 cents/kWh for industrial customers). Plus, it makes extensive use of renewable sources, particularly hydroelectric (i.e., dams) and wind energy. Oregon has a similar story to tell, with their own rivers, dams, tax breaks, etc., and is part of why Amazon elected to put a huge facility there.

Re:could've been huge. hydro failure killed 200,00

[93 Escort Wagon]

Don't worry - the only thing downstream from this dam is Portland.

Unless

[justthinkit]

Unless you count the 582 miles of cooling pipes.

Fail.

[PhillipNolan]

this exceeds the excessive inaccuracy ratings for slashdot. It helps if you actually read the links you include in your article. this page: http://upload.wikimedia.org/wikipedia/commons/e/ec/Pacific_Northwest_River_System.png, linked in the article, shows there are 5 dams below the wanapum. apparently the change in color was too confusing for you? The Columbia is only free-flowing below the Bonneville dam which is just upriver from Portland/Vancouver.

Re:WTF

[MachineShedFred]

It's more about being able to still have agriculture in the hundreds of thousands of acres that get irrigated from the reservoirs behind the dams. These hydropower projects had three objectives, all wildly successful for the last 50 years:

1. Flood control
2. Electricity generation
3. Irrigation of the high plains surrounding the Columbia River