The U.S. Army Corps of Engineers (USACE) is responsible for maintaining the shipping channel in the lower Columbia River (LCR). The LCR shipping channel has historically been maintained (through dredging) at an authorized depth of 40 ft, but a channel deepening project was proposed in the mid-2000s to increase the authorized depth to 43 ft, thereby allowing ships to load to a deeper draft for transit in the LCR. The intent was to provide an economic benefit by increasing shipping efficiency in the LCR. However, increased vessel size and draft have the potential to negatively affect juvenile salmon Oncorhynchus spp. populations in the LCR.