Streams of Life
Water in the American West

ThinkQuest ‘99

Drew ((email link disabled))

Lee ((email link disabled))

/27419/

Build Your Own Dam

While this might look like a project that is only fun for young kids who like to build stuff and make messes (and people like me) and has no educational value whatsoever, it actually can be education and entertaining to practically everyone. The first part is step-by-step instructions with links to images that show what's happening. The second part is a bunch of pictures with captions; great for those dam builders who can't find a good dam site. Another thing to remember is that there is more than one way to build a dam. Feel free to improvise.

You don't really need to have water running through your river the whole time, but it would add some challenge. I just used a bucket to dump water down my river because I had to figure everything out and needed to take pictures.

How to do it...

Materials
1x piece of 1" thick Styrofoam (something like 2' x 1')
1x long flexible plastic drain pipe
4x standard bricks
1x large concrete building brick
1x roll of duct tape
1x normal freezer bag
1x handful of small rocks

Tools
scissors

you either need a bucket that you can fill multiple times or a hose

Instructions

  1. Find a good site to build you dam at. I'm assuming that you are going to be using a normal street gutter that is on a hill. picture
  2. First you need to divert the river. Start by setting up the flexible drain pipe. Make it arc so that there is a large area for building your dam. It might need to be weighted down with bricks.
  3. Build a medium sized dam right under the drain pipe's intake. This will keep water from entering your workspace.
  4. Build a small dam right above the outflow of the drain pipe. This will keep water from coming back into your workspace. This is called a coffer dam.
  5. You might need to use a plastic bag to feed the water into the drain pipe. It should be weighted down with small rocks. picture
  6. Now you can start building your dam. First place the concrete building block perpendicular to the river (or where the river used to be). picture (with extra stuff)
  7. Cut the piece of Styrofoam to fit into the curve of the gutter. Place it in front of the concrete block, make sure it is touching the ground, and put a little bit of duck tape on it to attach it to the concrete block. picture
  8. Now tape the Styrofoam to the ground with long strips of duck tape. You won't be able to put time on the middle because your 'river bed' will still be wet. This will serve as the inflow to your (imaginary) power plant inside your dam.
  9. Place a cut open plastic bag in front of the Styrofoam. It should have a right angle in it and go up the Styrofoam a bit.
  10. Tape the edge of the bag (other than the middle) to the ground.
  11. Now place three or so bricks on top of the bad. Make sure the bag still comes over the top of the bricks. picture
  12. Your ready to test it out. Hopefully your dam will work well.
  13. Don't forget to clean up once your done. While it's hard to remove a dam like Hoover, yours should come apart easily. picture

After building the dam, my river sure was tame. That's just what dams do to real rivers.

This is how the bricks are placed in front of the Styrofoam. Notice the bag underneath.

Looking down at reservoir. Notice all the sediment building up behind the dam. Sediment builds up behind all dams. The Colorado is the siltiest river in the world. It also happens to be where our largest dams our. Sometime the reservoirs in the Colorado will fill with up silt and be useless. The dams will continue to work, though. They're designed for lifetimes of thousands of years.

Here's the reservoir filling up. This shot shows the general setup.

You probably don't want to leave your dam once your done with the project. Today a number of dams are being removed to restore the environment around them. In addition, many of our dams, today, are that practical. Sometimes it makes the most sense to tear them down.

Good spot for working.

The river is being lifted from its bed and diverted around the work site

Here's another view of the construction.

Yet another view.

The dam regulars the flow of the river. Preventing floods (which are often necessary to the surrounding environment) and also cuts bake on the flow.

There's the reservoir. Do you know what is the largest reservoir in the United States? If you guessed Lake Mead, which is formed by Hoover Dam, you are correct.

A view of the dam's back side. Notice the concrete construction block.