Draft Purpose & Need and Project Objectives
Purpose of the Proposed Action
The purpose of the project is to reduce congestion and improve functional deficiencies and traffic operations and safety for the traveling public within the I-25 and Arapahoe Road interchange complex, extending along Arapahoe Road from west of the Yosemite Street intersection to east of the Boston/Clinton Street intersection.
Need for the Proposed Action
The existing design and capacity of the interchange no longer accommodates traffic demands. Arapahoe Road is the critical east-west roadway link of the City of Centennial and an important transportation corridor supporting economic activity in Arapahoe County and the Cities of Centennial and Greenwood Village. Traffic volumes have increased substantially over the past 30 years due to nearby business park, residential and retail development. The I-25 and Arapahoe Road (SH 88) interchange complex experiences heavy traffic throughout the day, with high traffic volumes in the morning, noon and evening peak periods. Traffic volumes are projected to increase by over 30 percent through 2035. By comparison, traffic volumes on Arapahoe Road at I-25 are nearly double the existing and forecasted traffic volumes on Orchard and Dry Creek Roads at I-25. Without roadway improvements, drivers will experience increasing congestion surrounding the I-25/Arapahoe interchange complex.
Although recent (2010) interim lane improvements have been of benefit to interchange traffic movements, significant queuing continues along Arapahoe Road at the Boston/Clinton and Yosemite Street intersections due to the close intersection spacing and high turning traffic volumes. The two narrow eastbound through travel lanes on Arapahoe Road under I-25 cause traffic to slowly negotiate the southbound I-25 to eastbound Arapahoe Road double left turn, resulting in lengthy vehicle queuing on the southbound off-ramp that often backs up onto I-25, especially in peak periods. These conditions limit the capacity of the interchange and adversely affect through traffic on Arapahoe Road.
The I-25/Arapahoe Road area experiences a relatively high rate of accidents, particularly on Arapahoe Road both east and west of I-25. Emergency service providers have noted their concerns with difficulty responding to incidents in the narrow, barrier separated segment of Arapahoe Road between the I-25 off-ramp intersections.
Project Objectives
The objectives of the improvements should:
- Improve functional deficiencies and operational efficiency of the interchange complex and meet future traffic demands
- Improve safety for motorists, pedestrians and bicyclists
- Accommodate multimodal connections
- Be sensitive to and preserve the residential and business community character of the area through Context Sensitive Solutions (CSS)
- Mitigate adverse impacts
- Consider the economic importance of the interchange at the local and regional levels
- Create the best value, considering benefits, anticipated construction costs, life cycle costs, and potential for funding
This is an Arapahoe County, Colorado project website.
The I-25/Arapahoe EA is being conducted in conjunction with FHWA, CDOT, the City of Centennial and the City of Greenwood Village.
© 2010 David Evans and Associates, Inc.