16-036 Corps of Engineers determines 259 miles of Salmon River navigable

Published June 3, 2016

Idaho – Following extensive U.S. Army Corps of Engineers review, the Northwestern Division Commander, Brigadier General Scott A. Spellmon, signed a Finding of Navigability Determination for the Salmon River, from River Mile (RM) 0 to RM 259.

This decision is consistent with other long-established determinations made by the State of Idaho (1980) and the U.S. Coast Guard (1974) that the Salmon River in Idaho meets navigability criteria from its confluence with the Snake River upstream to the city of Salmon, Idaho. The Corps’ finding of navigability for the Salmon River (RM 0-259) is supported by 33 USC §401 et seq., 33 CFR §329; legal precedent; and historical research and literature review. 

The navigability study effort involved locating, researching and summarizing evidence of historical use and condition of the waterway, collecting technical and mapping information on the river system, and preparing an official report of findings. This navigability determination is pursuant to Section 10 of the Rivers and Harbors Act, which regulates work conducted below a navigable river’s ordinary high-water mark. Regulated activities include: structures built, excavation, dredging, or depositing material in the river, and “any other work that affects the course, location, condition or capacity of navigable waters.” 

Kelly Urbanek, Chief of the Regulatory Division for the Walla Walla District, which includes the state of Idaho, and other representatives of the Corps’ Walla Walla District, met with local congressional representatives and commissioners from Idaho, Lemhi, Lewis, and Nez Perce counties during April and May, to explain how the river’s new classification could affect those who do work the river. 

“During the coming year, we will be developing permit procedures to help applicants with the regulatory process. We will also meet with user groups and the public in several communities,” said Urbanek. 

The Salmon River and its tributaries are already subject to Section 404 of the Clean Water Act, requiring a U.S. Army Corps permit to conduct work or discharge material in the river. Because issuing a permit is a federal action, the Corps must consult with other federal agencies to ensure permitted activities do not violate other federal laws such as the Endangered Species Act. 

Public Notices and other Regulatory Program information are available on the Walla Walla District website at


Other water bodies in Idaho considered navigable by the United States and therefore subject to permitting under the Rivers and Harbors Act include: Bear Lake, Clark Fork River (from the mouth upstream to RM 4), Clearwater River (confluence with the Snake River to RM 40.5), the North Fork Clearwater River (confluence with the Clearwater to RM 57.9, including Dworshak Reservoir), Kootenai River (Bonners Ferry to the Canadian border), Pack River (from the mouth upstream to RM 1.5), Lake Pend Oreille (Albeni Falls Dam to elevation 2062.5 NGVD), Pend Oreille River (Idaho/Washington border upstream to Albeni Falls Dam) and the Snake River (Idaho/Washington border to RM 445.5). http://www.nww.usace.army.mil/BusinessWithUs/RegulatoryDivision/Section10Waters.aspx.  




509-527-7020     cenww-pa@usace.army.mil      www.nww.usace.army.mil


Release no. 16-036