Project: Boulder Flats Wetland Mitigation
Project No.: A011(624)
Key No.: 11624

The proposal of the Idaho Transportation Department (ITD) is to create wetlands at the Idaho 75 Boulder Flats Wetland Mitigation Site located between Goat Creek and Phantom Hill (milepost 139-140.5). The current roadway will be removed to reestablish wetlands.

Within the Timmerman to Ketchum corridor are several environmental impacts that require a mitigation plan. Pursuant to the Final Environmental Impact Statement (FEIS) for the reconstruction of Idaho 75 Timmerman to Ketchum, the Boulder Flats site was selected from among a dozen possible wetland mitigation sites. It was considered the most practical and cost-effective to mitigate for the entire corridor.

As design for the first phase of construction progressed, ITD continued early development of the wetland mitigation at the Idaho 75 Boulder Flats Wetland Mitigation Site located between Goat Creek and Phantom Hill (milepost 139-140.5). The intent of the mitigation site focused on wetland creation including the subsequent highway realignment to recreate sufficient wetlands to offset impacts from the construction of Idaho 75 further south.

Through the wetland delineation, engineering studies, and roadway design for the Boulder Flats site, it was determined the site was not viable due to substantial destruction of additional wetland area to recreate new mitigation wetlands.

ITD remains committed to fulfill its obligation to develop wetland mitigation for the Idaho 75 Timmerman to Ketchum corridor. A plan is currently being developed to identify a variety of options to fulfill the mitigation commitment in the FEIS.

Development of a wetland mitigation plan will include a cooperative effort from the U.S. Army Corp of Engineers, U.S. Environmental Protection Agency, Federal Highways Administration, and other key agencies and stakeholders.

The Idaho Transportation Department values your input. Feel free to contact us for more information.

• Email us - please include your name and address
• Download a comment form (word doc)

Project Manager
mike.scott@itd.idaho.gov
(208) 886-7806

District 4 Public Information
nathan.jerke@itd.idaho.gov
(208) 886-7809