How to Build Your Own Four Sluice Mini Dam in Your Backyard

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If you enjoyed our other video on how to make a miniature dam, then we are confident this four sluice version will also tickle your fancy. Not only does it look like the real thing, but it is actually pretty easy to build.

Follow this guide to find out how. 

As you can imagine, you'll need some tools and materials before you get started.

Materials and gear needed

• Scrap wood
• Scrap metal sheets or strips
• Metal wire
• Motor
• Cement mix and sand
• Scrap metal strips
• Angle grinder
• Welding gear and safety equipment

With all your gear in hand, it is now time to actually get stuck in.

Step 1: Prepare the ground and create the dam frame 

The first step is to create a trench to house the dam and create a reservoir for the dam. With that complete, mark out the position of the dam and excavate the trench floor and sides accordingly. 

With that done, excavate some smaller transverse trenches across the main footprint of the dam to mark the position of the sluice gates. Next, take some steel frames and line the bottom of the dam. 

Using some more pieces of steel wire, build up the sides of the dam to create a cage frame for the main walls of the dam. Ensure these pieces are well sunk into the walls of the trench. 

For the center body of the dam, add steel wire piles into the ground, and build up the steel frame around them as needed. Ensure you leave some space at the base of the dam in line with the sluice trenches for the sluice gates.

You will also need to create wireframes for the front buttresses of the dam. 

Step 2: Pour the concrete

With the frame of the dam now complete, we can prepare it to receive concrete. Since the frame is open, we'll need to add in some shuttering to ensure the concrete fills the shape of the dam.

Add pieces to the buttresses and main sections of the dam as needed. For the vertical sections of the dam, you'll need to hold the shuttering in place using some temporary piles. 

You can use anything for this, but ensure the material is strong enough to hold the shuttering tight to the steel frame. With that done, you can now mix up your concrete as instructed. 

Once ready, begin to pour the concrete mix into the dam mold. Periodically tap and stir the concrete around to remove any air gaps and fill the mold entirely. 

Once you've filled the mold, ensure you level off and smooth down the topmost surface of the concrete. 

Leave the concrete to cure. 

Step 3: Build the main sluice gates

While the concrete is drying, you can now turn your attention to making the main sluice gates. Take your scrap tubular steel and cut it down into a series of lengths just slightly longer than the height of the dam. It will need to be larger enough to allow the main sluice gate to move freely within it. 

With that done, cut a groove down the centerline of one edge of each strip to form a rail. Next, weld the grooved steel lengths together as shown in the video. 

With that complete, create the frame for the sluice gates, and weld as needed. Next, measure out and cut a pair of sluice gates from some steel sheet. These will need to move between the rails freely. 

Now, make the main winch system for the sluice gates as shown in the video. Weld into place at the top of the sluice gate frame. Then insert the sluice gates and tie them to the winch. 

Once done, paint the entire assembly as needed. 

Step 4: Complete the main dam

Once the concrete is fully cured, remove all boxing and shuttering to expose the base concrete. TIdy up the sluice holes in the main dam structure, as needed. 

With that done, take the main sluice gate assembly, and pile it into the ground on the reservoir side of the dam. 

With that done, add some more shuttering to the rear of the dam to box in the sluice gate. Once ready, pour in more concrete and leave to set, thereby fixing the sluice gate into place. You can also add more concrete to the "roadway" of the dam if needed. 

While the concrete is still relatively pliable, you can also make a set of small railings to line either side of the roadway. Once ready, install in place. 

Next, concrete the underside of the front sluiceways with concrete too. 

Step 5: Install the sluice gate actuator and finish the project

With the main dam structure effectively complete, we can now move on to motorizing the sluice gate. Install a motor to one end of the sluice gate winch. 

Create a plinth to mount the motor to, and install all pieces, as needed. Connect the motor to a power supply and test it. Adjust as needed. 

Once happy, close the sluice gates, and flood the reservoir side of the dam. Now your dam is finally complete.

Open the sluice gates, and watch your dam work in its full glory. 

If you enjoyed this little project, you might enjoy making another interesting mini-dam project too? Happy building.