Refers to the frequency and duration of periods of saturation or partial saturation during [[soil]] formation, as opposed to altered drainage, which is commonly the result of artificial drainage or irrigation but may be caused by the sudden deepening of channels or the blocking of drainage outlets.
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'''Drainage Class''' refers to the frequency and duration of periods of saturation or partial saturation during [[soil]] formation, as opposed to altered drainage, which is commonly the result of artificial drainage or irrigation but may be caused by the sudden deepening of channels or the blocking of drainage outlets.