Why it matters: The Conservancy's connectivity work, including the installation of improved culverts and road stream crossings, matters because it results in more accessible, resilient and safe road systems for people, and enables migratory fish to thrive.
The Great Lakes basin is home to a multitude of migratory fish that rely upon both the Great Lakes waters -nearshore areas, coastal wetlands, and offshore systems-as well as the connecting rivers and streams that provide spawning and rearing habitat. Maintaining the flow of water from rivers’ headwaters all the way to the Great Lakes is critical to the freshwater fish species that spawn and feed in them. Less than 25% of Great Lakes basin tributaries remain accessible for fish. The importance of these tributaries cannot be understated; they significantly influence nearshore habitats, provide spawning habitat to fish, and transport important nutrients through inland aquatic systems.
Thousands of dams and hundreds of thousands of inappropriately designed road-stream crossings severely restrict connectivity within the Great Lake basin’s waterways. Approximately 60%* of road crossings in the Great Lakes basin impede the natural flow of rivers and streams, which negatively impacts fish and their habitats. Faulty, undersized, or perched culverts can lead to the flooding and damage of roads and property. Washed out roads can create a major safety concern, especially in times of severe flooding.
Our goal is to have both thriving migratory fish populations and resilient road systems. We are working to ensure that all dam and road-crossing infrastructure maximizes organism passage with consideration of aquatic invasive species, and minimizes sedimentation and risk of failure.
*Januchowski-Hartley, S. R., P. B. McIntyre, M. Diebel, P. J. Doran, D. M. Infante, C. Joseph, and J. D. Allan. 2013. Restoring aquatic ecosystem connectivity requires expanding inventories of both dams and road crossings. Frontiers in Ecology and the Environment: 211-217.
Strategies:
- Establish and participate in a regional connectivity collaborative to create shared regional goals, and alignment of funding and action to meet these goals
- Develop and disseminate science and information to optimize barrier removal
- Establish and implement basin-wide standards for new and re-engineered crossings and passage at dams
- Restore priority areas at scale
