Rideau Canal National Historic Site of Canada

Locking Through

Design Project

Visualizing the concept of a lock can be difficult, and can be made easier if you are able to see a model of a lock. Students can design and build a relatively simple model of a lock right in the classroom.


  • paper or toy boat
  • 2 rubber basins (6' - 10' deep)
  • rubber tubing
  • bathtub or sink caulking
  • a cork or other plug
  • water
  • Model Lock diagram
  • Tool to puncture holes


1. Provide the students with the diagram of a model lock. Have them model this with the materials provided.

2. Provide students with just the materials, and have them create something which illustrates water movement in a lock. Hopefully you will end up with some variations on the theme.

Design Problem

The locks on the Rideau Canal raise and lower boats to another water level. Boats may enter the locks and be raised by adding water into the lock or lowered by draining the lock. There are no electric pumps used to move the water. Tunnels exist between the locks so water can move through them. Using the materials provided here, design a model lock showing how the water flows into or out of the locks. Remember, no electricity or pumps are used, just a simple scientific concept. The water levels in each lock chamber(the basins) must be able to be lowered or raised and remain even. How will you achieve this?


1. Punch 2 small holes in opposite sides of one end of the basins, close to the bottom. Place them end to end.

2. Run tubing from one basin to the other, so it appears that 2 tunnels are running between the basins. These represent the sluice tunnels.

3. You may need to put some caulking around where you drilled holes in the basin and put the tubing. This will help prevent leakage if need be.

4. In order to illustrate water movement from one basin to another, basins should be at different levels. Place some books under one basin to make it higher.

5. Use the cork to plug the tubing in the upper chamber. Then fill it three quarters full of water. Put a toy boat in the water.

6. Pull the plugs and watch the water drain out. It's that simple. Water is moving out of the upper lock and flowing into the lower lock, all by gravity.

7. Try this! With all the water in one basin, place the other basin on an equal level. Now pull the plugs and see what happens. Will all the water flow out? The water should even out in both basins. Gravity is still pulling water from one basin to another.