March 30, 2017 17:42 Updated Follow Indiana Natural, Scenic, and Recreational River System Law describes the criteria and purpose of the River system. Related articles Need Help? Have problems? Who do I call? What Agency? What is a River Basin Commission? What is Subsidence Insurance? And do I need it? If I have a question about a snake, bird, plant or other natural feature, who do I contact? How can I find out if there are old underground mines under my house?