In 1999, a Billabong was constructed to the southeast of the two experimental wetlands as part of the second phase of the park. This area replicates the habitat that might be found at an oxbow lake. Water is gravity fed into the system from the Olentangy River only during times of high flow. Visitors are sometimes surprised to see the area almost totally devoid of water. However, this is completely normal, particularly during the summer months. A Mesocosm Compound for smaller scale research was built at the same time as the Billabong.
