I-25 and Arapahoe EA and FONSI

August 2012 - This Environmental Assessment (EA) was prepared under requirements of the National Environmental Policy Act (NEPA) to determine if the Action Alternative could have significant impacts on the human environment. The purpose of the project was to reduce congestion and improve traffic operations and safety for the traveling public within the I-25 and Arapahoe Road interchange complex.

Environmental Assessment August 2012

Environmental Resource Technical Memoranda July 2012

Traffic Noise & Vibration Impact Assessment Tech Report April 2012

Air Quality Evaluation March 2012

Biological Resources Tech Memo July 2012

Hazardous Materials Assessment May 2012

Historic Resource Evaluation Tech Memo April 2012

Visual Resources Tech Memo April 2012

Technical Design Documentation July 2012

Existing Conditions Tech Memo November 2011

Structure Selection Report November 2011

Arapahoe Road Pedestrian Grade Separation Evaluation February 2012

Design and Utilities Tech Memo November 2011

Drainage Tech Memo/Water Quality and Detention Storage Analysis February 2012

Construction Phasing Tech Memo November 2011

Improved Partial Cloverleaf Cost Estimate April 2012

Eagle Hardware/Gart Highway Access Appeal Court Decision February 1997

Final Travel Forecasting Summary May 2012

Final Interchange & Supplemental I-25 Crossing Alternatives Tech Report August 2011

Final Safety Assessment Summary August 2011

Walnut Hills Neighborhood Traffic Study July 2011

EA Newsletter #1 April 2010

EA Newsletter #2 September 2011

EA Newsletter #3 September 2012


February 2013 - This Finding of No Significant Impact (FONSI) was prepared under requirements of the National Environmental Policy Act (NEPA). Preparation of this FONSI was a cooperative effort by the Federal Highway Administration (FHWA) and the Colorado Department of Transportation (CDOT) as joint lead agencies; Arapahoe County as project sponsor; and City of Centennial and City of Greenwood Village as cooperating agencies.

Finding of No Significant Impact FONSI February 2013


Also included:

Final System Level Feasibility Study June 2008