Sections of the canal need to be drained of water in order to complete the work.

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The Spanish soon drained the water away, and started building.

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More than 4ft (1.2m) of water had drained out of the lake at Tunstall Park on Wednesday night, the Coal Authority said.

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Turkey, sensing a lucky escape, came out after the break with renewed purpose and posed a greater threat as the pitch slowly drained of the excess water.

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The clay has the effect of storing rainwater, reducing the impact of flooding, while during dry spells, the water is gradually drained back into the rivers and streams.

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Over time, the channel has been altered, wetlands drained and the flow of the water controlled and diverted for use in nearby cities and farms.

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Police said water had to be drained from the mine.

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The canals nearby had been drained for maintenance work, so there was no water easily available when the firemen arrived.

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They also need to have reservoirs built to supply the water, and if natural lakes are used they are drained.

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But if engineered right, deep water yields higher returns than many onshore projects because the fields are compact and easily drained.

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