I-84, Karcher Interchange to Five Mile Environmental Study

Project Facts

Project Number: A010(002)
Key Number: 10002

The Idaho Transportation Department (ITD) is conducting the I-84, Karcher Interchange to Five Mile Environmental Study through the GARVEE Transportation program. The study will identify long-term improvements to I-84 from Karcher Interchange in Nampa to Five Mile Overpass in Boise. The completed study will identify the final "build-out" for I-84.

An environmental document will be prepared for the Karcher Interchange to Five Mile Road segment in accordance with the National Environmental Policy Act (NEPA). An environmental document is a full-disclosure document detailing impacts of the proposed improvements to the human and natural environment.

Description

The study limits extend from the Karcher Interchange in Nampa to the Five Mile Overpass in Boise. This section of I-84 is primarily a four-lane divided highway in Canyon County and an eight-lane divided highway in Ada County. With the addition of the new Karcher Interchange, there are currently six interchanges. A seventh interchange at Ten Mile Road is expected to begin construction in early 2009.

The comprehensive study will allow ITD to develop possible alternatives for highway improvements. Several scientific studies including a noise and air quality analysis, along with traffic, structure and geotechnical studies will be conducted. The environmental document also includes:

A long-term improvement plan that defines a comprehensive package of recommendations for managing and improving the transportation system in the study area.

A conceptual plan that identifies design options for the interstate mainline and existing interchange.

Environmental documentation that identifies the impacts the proposed improvements may have to the human and natural environment.

A preferred alternative that will be selected based on a comprehensive evaluation of environmental impacts, cost, engineering aspects and public opinion. It is possible that a “no-action” alternative could be selected.

Right-of-way requirements that will identify additional property near the project that will need to be purchased for future construction.

The study will include a collaborative involvement process with the public, local jurisdictions and property owners to determine the best options for improvement. Public meetings will be held throughout the study process.

Background

Most of the Treasure Valley was rural when I-84 was first built in the late 1960s. Population growth and development since then are causing a rapid shift from a rural to suburban setting.

The I-84 Corridor Study, completed by the Community Planning Association of Southwest Idaho (COMPASS) and ITD in 2001, identified long-term needs for the interstate. This environmental study will rely heavily on the recommendations of the 2001 study and will finalize the planning and design process for this section of the interstate corridor.

The Communities in Motion: Regional Long-Range Transportation Plan for Southwest Idaho, adopted by the COMPASS Board in 2006, recommended maintaining and/or rebuilding existing interchanges to accommodate widening the interstate. It also recommended conducting a corridor-level alternatives analysis that would examine improvements such as High Occupancy Vehicle lanes, ramp metering and improvements to bus operations.

Funding and Schedule

The I-84, Karcher Interchange to Five Mile Environmental Study is funded with GARVEE bonds. ITD began the study in January 2007. The study should take 36 months to complete.

Compliance with Title VI of the Civil Rights Act

The Idaho Transportation Department (ITD) is committed to compliance with Title VI of the Civil Rights Act of 1964 and all related regulations and directives. ITD assures that no person shall on the grounds of race, color, national origin, gender, age, or disability be excluded from participation in, be denied the benefits of, or be otherwise subjected to discrimination under any ITD service, program, or activity. The department also assures that every effort will be made to prevent discrimination through the impacts of its programs, policies, and activities on minority and low-income populations. In addition, the department will take reasonable steps to provide meaningful access to services for persons with Limited English Proficiency.

Contact

Contact
comments@itd.idaho.gov
Phone: (208) 334-4444
TDD: (208) 334-4458
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