Bonneville Dam, Oregon

To break up the drive a bit on our way home, we stopped at Bonneville Dam. We do love a good dam in this family, and we seek them out whenever possible. We feel we are getting quite a good series of dams under our belts! :) This dam is quite interesting because of the changes made in it over the years. We went on a tour of the powerhouse and enjoyed it immensely!

Huge generators (turbines are below, with the orange stripe)

Junie by one of the stator coils

Our tour guide told us that a huge chunk fell off of this mountain and dammed the Columbia River in Prehistoric times. Much of that landslide later eroded away, but that's what gave the river its distinctive shape and two-channel flow pattern.

We loved watching fish jump up the fish ladders

And Daisy also loved this huge turbine, evidently.

Fish ladder from below

Lampreys! If there's one piece of information I know in this world, it's what a lamprey has: a round sucking mouth with rasping teeth. I learned it in 10th-grade biology and I have repeated it frequently ever since (ask anyone). So you can imagine my pleasure and delight at seeing one in the flesh. Round sucking mouth! Rasping teeth! It's all there.

Seb poses precariously on a hill

Hoover Dam

I interrupt our Denmark Unit to bring you this special coverage of the Hoover Dam. Would you believe me if I said the boys were just as excited about going to the Hoover Dam as they were about going to Disneyland? Our trip to Flaming Gorge just whetted their appetites (the Flaming Gorge guide kept giving stats in relation to the Hoover Dam), so they'd been looking forward to it for a long time. Unfortunately, kids under 8 can't do the longer tour at the Hoover Dam, but we did get to see the powerhouse and everyone seemed content with that. Junie was extra heavy and squirmy and we hadn't brought the stroller, so Sam and I were definitely content with that!

Seb loved this huge wall diagram of the path of water through the powerhouse and dam. Probably because he has drawn many a similar diagram, in his day.

Tunnel toward the old diversion tunnel

The enormous penstock---we got to walk right over it

Powerhouse (Nevada side)---7 of the 15 enormous turbines

Intake towers

Outside 

One of many re-constructions created after we got home (note powerlines coming out of powerhouse toward transformers)

Reservoir cookies

This was a spur-of-the-moment idea I had one day when we didn't have many activities planned. I told the children we were going to make reservoir cookies! They are just kiss cookies with ganache filling instead of kisses. :) Of course you could use any kind of thumbprint cookies, but I'm not as fond of the "butter/shortbread cookie" as I am of peanut butter, so this is what we did. I see I haven't posted the Kiss Cookie recipe before, so here it is, modified for "reservoirs":

Reservoir Cookies

2 sticks butter or margarine (1 cup)

1 cup peanut butter

1 c. sugar

1 c. brown sugar

2 eggs

2 t. vanilla

3 c. flour (about 15.8 oz.)

2 t. baking soda

1 t. baking powder

1/2 t. salt

Roll dough into balls, then roll in sugar. Bake at 375 for 9 minutes. Immediately after removing pan from oven,  make an indentation in the middle of each cookie with your thumb (it didn't burn me, but maybe I'm strange) or a small lid (e.g. from a lemon juice or vinegar bottle). Pour chocolate filling (see below) into each hole to make a tiny reservoir or lake. For more complicated reservoirs, make bigger cookies and add chocolate chip dams, incoming tributaries, etc.

Chocolate Reservoir Filling:

1 c. chocolate chips or semisweet chocolate, chopped

1/4-1/2 c. evaporated milk or cream

Combine chocolate and 1/4 c. of milk or cream in glass bowl and microwave for 1 minute on high. Stir until smooth and glossy. Keep adding milk or cream and stirring well until the consistency is spoonable, but not too runny. You can also add 1 t. of corn syrup for glossiness, if desired.

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The real fun of this came in making bigger cookies that could convey more complicated data! We made a sample of each main type of dam, embankment dams and masonry dams.

Here is Abe's

And Seb's, an Arch Dam

Oh how we enjoyed gobbling these up!

Flaming Gorge Dam

The culmination of our study of dams was a trip to Flaming Gorge Dam in Eastern Utah. Upon looking up our route on the map the day before we left, we were excited to see there would be two other dams and reservoirs along the way! The boys were looking out for them with their beady little eyes the whole time we drove. Here is the first, a small embankment dam called Mountain Dell, I think?

So lovely in the morning light!

And the next, also embankment, was Echo Dam and Reservoir. The water level here was really low!

We were also pleased to spot lots of windmills as we drove!

Flaming Gorge itself is gorgeous! (ha ha) It goes on for miles (we didn't nearly drive around it all)

We enjoyed driving across this bridge as we got close

From the top, the dam isn't that huge---I assumed the water wasn't that deep, maybe 100 feet or something. But once we got around to the other side . . . 

we could see that estimate was way off! I think our guide said it's 500 feet high. It's even a bit longer from side to side than Hoover Dam---though much, much shorter in height!

It was so exciting to see all the parts of the dam---we could hardly believe that the tour let us go into the powerhouse and see the generators at work! The children were SO curious about everything (the guide said she'd never seen children like them---er. . . I believe her exact words were that they were the "most dam knowledgeable" kids she'd encountered on this tour. Ha ha. :))

Power lines. It was stormy, and not too comforting to hear another guide tell ours as we left for our tour, "Just make sure you don't get hit by lightning!" This impressed the children greatly, and when they asked if the dam had been hit by lightning before, our guide replied, "Oh yes---lightning has hit the dam, the powerlines, the visitor's center---we all ended up on the floor after that one!" It added a delicious thrill to our visit.

Looking down

Sluice gates, leading to the penstocks

Inside the powerhouse---three big generators!

Malachi. That dark grey shape in the background is an old turbine.

Looking up from the bottom

These were interesting---hollow jet valves, I think they were called? They're an alternate release system, in addition to the spillway. They can bypass the turbines and let water out here if they need to work on the generators or release water pressure a bit. Our guide said these were in use all last summer. The spillway (not pictured---it's higher up), on the other hand, has only been used once, in 1983!

Here's the end of one of the diversion tunnels they used while constructing the dam

Reservoir from above

And, looking the other direction, the top of the dam

It was a great field trip, well worth the long drive and the late night getting home---especially since we got to enjoy views like this as we drove!

Building dams on beach

We were really excited to get to studying dams, because that was one of the whole reasons we did this unit: the children (especially Seb) love dams! Our previous study of water pressure and waterfalls and mills made it really easy to understand the potential energy that can build up in a head of water. We drew lots of diagrams of how dams work:

One of Seb's diagrams

I wanted to have the children make a dam, but wasn't sure where to get enough sand/mud to make it fun. Finally realized the beach would be perfect (we brought some of our own gravel and big stones to use with the sand). It was so fun to watch all the different models everyone came up with, and the modifications they made as they discovered what worked and what didn't! Next time we will also bring large tongue depressors to use; I saw a video using those and popsicle sticks, and it looked like they worked quite well.

We did have one casualty to this activity: my large square rubbermaid container, which apparently floated out to sea. Other than that, we had a great time! :)

Such busy workers!

Junie was quite, some would say TOO, brave and independent at the beach. She went everywhere! When she spied these ducks, she took off like a shot after them, quacking frantically as she went. I had to run to catch her so she wouldn't follow them right into deep water!

"You are not a duck!" I said, and this was her sad response.

This was quite an effective dam---using my good cake pan, of course

Directing the flow

Is this baby wearing brown leg warmers?

This was another day---we built an arch dam with clay and cardboard, to measure the strength of different arch arcs (?) and determine which type of arch held the most water before failing. Very interesting.

One night this week we also watched David Macaulay's documentary Building Big: Dams. It's excellent; one segment of a 6-part series which we hope to watch the rest of sometime. We got it on Netflix.