Stream Restoration in a time of Systemic Change
– the Story from the Great Lakes Region
Robert Barr
Research Scientist
Center for Earth and Environmental Science
Department of Earth Sciences, IUPUI
It is humbling to try to give an overview of a region with a central watershed that has a drainage area of 295,200 square miles. That is over four and a half times larger than the Chesapeake Bay watershed. The Great Lakes basin is one of the world’s largest freshwater ecosystems. The basin contains 84% of North Americas surface freshwater – and about 21% of the worlds surface fresh water supply. Over five hundred major tributaries flow into the five lakes in this basin along with thousands of smaller streams. The streams and rivers flowing into the basin can originate in large natural areas to the north and equally large heavily modified drainage basins in the south. While it is a challenge to talk about the status of stream restoration in a basin this size, it would be a disservice to this remarkable ecosystem to speak about in generalities – no matter how superlative they might be. Like other drainage basins in North America and throughout the world, the Great Lakes basin is responding to climate change. A quick look at the now standard Functional Pyramid tells us that if a foundational portion of the pyramid (climate and geology) shifts, the other components (hydrology, hydraulics, geomorphology…) must respond. How the systems respond appears to depend on how modified the stream is. We regularly see, in the southern part of the basin, rivers that are detached from their floodplain tear their banks apart during a flood and floods are becoming much more frequent. Streams that still have a functioning geomorphic floodplain have room to adjust, the more confined streams do not. Rivers in the basin were modified by urbanization, agriculture, logging, mining, and thousands of dams. Restoration has been more patches than restoration, often driven by one concern or one species of concern. The changing climate is making disturbance more systemic, forcing researchers and practitioners to think more broadly about what restoration is. How do you restore 40-miles of degrading channel inside a forested riparian corridor? In this presentation we will discuss our evolving approach and our foundational principle – Do No Harm!
About Robert Barr
Robert Barr is a research scientist (fluvial geomorphology and hydrology) at the Center for Earth and Environmental Science at IUPUI. His primary research focus is on understanding the physical processes necessary to achieve and maintain healthy stream systems. Bob has participated in numerous large-scale stream assessments, including the Kankakee and Maumee Rivers in northern Indiana, and Eagle Creek and White Lick Creek in Central Indiana. Bob’s current projects include the Indiana Fluvial Erosion Hazard Mitigation Program and the School Branch National Water Quality Initiative. In addition to his academic research interests, Bob has served as a consulting hydrologist and fluvial geomorphologist for over 16 years.