It appears that this dew pond near Over Haddon in Derbyshire has not been used for while as there is no longer any water in it and is filled with fresh verdant grass. Dew ponds apparently don't really get most of their water from the early morning dew as the name might suggest but from rain water via the heavens. Dew ponds are useful in isolated areas where there is no decent supply to water a farmers livestock. They have been used in different parts of the country for centuries though obviously not always made from concrete but clay.
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