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Water reservoir can be defined as a manmade or natural storage area where a fixed amount of water is stored that can be drawn off for irrigation. Unlike rivers, water reservoirs do not fluctuate greatly over short time periods aiming on catching rainwater during wet season or impounding water from rivers during periods of higher flows that allows using the stored water in dry season for irrigation. With regards to your question, if If water is stored and closed-off in the ditch, then it can be considered as a water reservoir.
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