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Valve and Pipes Inside the Dam
At the turn of the 20th century, Dellwood Park was turned into an amusement park by the Chicago and Joliet Railroad. The park offered swimming and boating in a large lagoon created by damming Fraction creek in two places. The natural limestone dells provided the perfect place to hold in the water. This appears to be a valve that would regulate the flow of water from the upstream dam to the downstream dam.