Channel Adjustment Following Culvert Removal from Forest Roads in Northern California, USA

Removing fill material from forest roads significantly reduces sediment erosion in the first year, with 86% of erosion attributed to channel incision and bank erosion. A study at Redwood National and State Parks found that crossings removed in the first year yielded an average of 7.71 m³ of erosion per crossing, while older crossings showed a net gain of sediment. The research highlights the importance of excavating to bedrock or coarse material when recreating streambeds and identifies channel bulges as areas prone to erosion. First storms were crucial in mobilizing sediment, with coarsening of channel substrate most pronounced in the first year post-removal.

Maurin, L. P., & Stubblefield, A. P. (2011). Channel Adjustment Following Culvert Removal from Forest Roads in Northern California, USA. Ecological Restoration, 29(4), 382–391. https://doi.org/10.3368/er.29.4.382