Dew pond on the South Downs, UK. Dew ponds are small round ponds traditionally made by digging a shallow concave pit and lining it with clay. They provide water for livestock in areas such as the South Downs where precipitation is absorbed by the porous underlying rock (chalk in this case) instead of running off the surface to form streams. Despite the name, such ponds are replenished largely by rainfall, not dew. Photographed in July, near Ditchling, East Sussex.