6. BRINGING WATER TO YOUR PONDS

(134) If the stream that supplies your water is not much higher than your ponds, it may be difficult to get the water to run down when you want to fill them.

(135) By building a barrage, you can raise the level of the stream so that water will run down more easily into your fish ponds.

(136) You can build a simple barrage using a woven mesh of tree branches like the one shown at left. You can also use loose stones or rocks or logs set into the stream bottom.

(137) A barrage does not hold back all of the water that runs down the stream. Depending on how it is built, some of the water will be held back and some of the water will flow through or over the barrage.

(138) If the tree branches, logs or rocks are placed tightly together, the water level behind the barrage will be higher.

(139) If the tree branches, logs or rocks are not placed so tightly, the water level behind the barrage will be lower.

(140) If you build a barrage and too much water flows through, you can hold back more water by putting more branches, logs or rocks on the barrage.

DIGGING A SUPPLY DITCH

(141) After you have built a barrage and the water behind it has reached its highest level, you will need to dig a supply ditch to take the water to your ponds.

(142) Begin by digging the supply ditch just behind the barrage where the water is deepest. However, dig it in such a way that the water in the stream will not yet flow into the ditch.

(143) You can do this by starting the supply ditch about 1 metre away from the edge of the water. When you are ready to fill your ponds, you can remove this 1 -metre strip and the water will flow into the ditch.

(144) The ditch should run near the shallow ends of your ponds and in the same direction as the stream that supplies your water.

(145) The ditch should have very little slope. You can use a straight board and a mason's level to help you dig your ditch.

(146) When you reach your highest pond, the ditch should be near the inlet. Continue to dig your water-supply ditch until you reach your lowest pond.

(147) When the supply ditch is past the end of the lowest pond, continue to dig it downhill for about 10 metres.

(148) Then bring the ditch slowly to the surface. That way, when you fill your ponds, any extra water will flow out at ground level.

(149) Now dig a small ditch to connect the inlet of each pond to the supply ditch. Keep its bottom level horizontal.

DIGGING A RETURN DITCH

(150) You will also need to dig one or more ditches to take the water back to the stream when you empty your ponds.

(151) These are called return ditches. How you dig them will depend on how your ponds are placed and how near they are to the stream. Try to choose the easiest and shortest path to take the water back to the stream.

(152) If your ponds are near the stream, the easiest way to get the water back is to dig a return ditch from the outlet of each pond straight to the stream. You can also use one ditch for two ponds.

(153) If your ponds are not near the stream or if you cannot dig a ditch straight to the stream, dig only one return ditch along the outlet side of your ponds, which can take all the water from all the ponds.

(154) Start this ditch at the outlet of your highest pond. The ditch should run past the outlet of the lowest pond and then back to the stream.

(155) Now, dig a small ditch to connect the outlet of each pond to the return ditch.

BUILDING A SLUICE TO CONTROL THE WATER FLOW

(156) When you have built your ditches, you will need a way to control the flow of water from the stream into your supply ditch and from your supply ditch into the inlet ditches of each of your ponds.

(157) To control the flow of water into your supply ditch, you can build a sluice.

(158) This sluice will have three slots in each wall. Two sets of slots are for wooden boards and the third set is for a screen to keep out wild fish.

(159) Build this sluice at the top of the supply ditch just behind the 1 -metre strip of soil that you left at the edge of the water when you began digging the ditch.

(160) The drawing shows you how to build a wooden sluice for the supply ditch at the stream.

(161) Pack the space between the boards with good clay soil to keep the water from leaking through.

(162) Do not put in the screen until you are ready to use the sluice. Put it aside so that it will not be broken.

(164) Later, when you are ready to fill your ponds, you will control how much water will reach your ponds by removing some planks from the sluice.

(165) For better control of the water supply to each pond, you can build smaller sluices in the supply ditch at the lower corners of each inlet ditch, as shown in the drawing.

(166) With this sluice you need only one set of boards. The drawing below shows you how to build such a sluice.