Evaluation of Splash Dam 2 and Splash Dam 3 on Marble Creek

Posted in Conservation
Evaluation of Splash Dam 2 and Splash Dam 3 on Marble Creek

Plateau Archaeological Investigations conducted a significance assessment of two historic splash dams (Splash Dam 2 and Splash Dam 3) in the Marble Creek drainage on the St. Joe National Forest.  The evaluation was done to consider the effects of a plan to provide passage for native salmonids around blockages such as the splash dams.  The Marble Creek Splash Dam Project is part of the larger fishery enhancement plan for a regional utility’s Federal Energy Regulatory Commission (FERC) licence.

This evaluation was conducted under an ARPA Permit issued by the Idaho Panhandle National Forest.  Splash Dam 2 consists of a crib-style, rock-filled structure with spillways, lift gate, and two buffer dams.  Splash Dam 3 is a “rollover” or free flow dam that consists of a crib-style, rock-filled structure.  When surveyed in August 2010, each of the splash dams had already undergone extensive erosion.  The continued presence of each of the dams on Marble Creek stand as physical documentation of the logging frontier in northern Idaho, and each dam is considered eligible for inclusion on the National Register of Historic Places.

The project proponent plans on partial removal of each structure.  Plateau recommended that any destruction or alterations to the sites be recorded with Level II mitigation.  Though the structures are regionally significant, they do not meet the criteria for national significance, which would require a full Historic American Engineering Record (HAER).  Since these locations are extremely remote, a trail marker, complete with historical information will be erected on the main trail (261) to make hikers aware of the locations of the dams.

Location: Shoshone County, Idaho