How Restoring Rivers can Make us More Resilient
Climate change will fundamentally impact our streams and rivers in ways that threaten species, ecosystems, and communities. In the Northwest region, we are already concerned that increased rain and flooding in the winter, coupled with decreasing summer streamflows and smaller mountain snowpacks, will significantly change our rivers’ systems in the coming years and decades.
That is why we are working with our partners (including state and federal agencies and local watershed groups) to think about how we can restore rivers to be ‘resilient’ in the face of the increasingly extreme and frequent floods and droughts that are expected to occur with climate change. By ‘resilient’ we basically mean that a natural system can undergo some change without losing essential functions (such as providing a water supply, habitat for fish and wildlife, filtering and storing groundwater, cycling waste and nutrients, etc.)
I attended the River Restoration Northwest conference last week to present a poster) on just this issue – how can we use restoration to build resilience?
Through our Community-Based Restoration Program with NOAA we have tried to ensure that stream barrier removal projects that benefit migrating fish also incorporate the broader concept of resilience. For example, we reduce flood risk from constricted culverts and increase cold water habitat for threatened salmon and steelhead. We also try to realize other community benefits by working on projects that are part of a larger community riverfront revitalization effort (like Kellogg Dam removal in Oregon) or improving public safety by removing a ‘high hazard’ dam (like Hemlock Dam in Washington). By combining restoration science with our on-the-ground restoration experience, we have learned that we should design projects for a range of climate and hydrologic conditions and connect rivers to floodplains to enhance natural flood control and water storage capacities.
The feedback I received from fellow restoration practitioners at the conference was promising in terms of using the science of restoration to adapt to climate change, and I hope we can grow this discussion of resilience with our partners in the future. Several practitioners agreed we need to act now to design our projects for anticipated climate impacts; however, some practitioners thought that this might mean over-designing projects for climate effects that are uncertain or longer-term than the life of a particular project. But this is precisely the point – it is the uncertainty and longevity of climate change that makes restoration a useful tool in adapting rivers for the future. We cannot restore our rivers to how they were historically if things are going to change. Rather, we should restore them so they can be resilient in the face of such change.