Climate change scientists have noted changes in Pacific Northwest hydrology, including reductions in the size of glaciers, less snowpack, and earlier peak stream flow in many rivers. These trends are expected to continue, along with increasing flood size, and decreasing summer low flows. Typically, the size of water-crossing structures like culverts and bridges is based on stream width. As the size of floods increases, so will stream width.
WDFW’s web application can help you understand how the stream width at your project site may change in the future -- the 2040s and 2080s. With this information, you can make an informed decision about the design of your new culvert, bridge, or habitat restoration project. Culverts and bridges built to accommodate higher stream flows are less likely to fail and block fish, which reduces future maintenance and repair costs.
Learn more about the science behind our climate change web application in the project report Incorporating Climate Change into the Design of Water Crossing Structures.