Two alternatives will be evaluated in the environmental assessment (EA) – the No-Build Alternative and the Build Alternative. The following provides a description of alternatives. This memorandum describes the redesign process that ODOT used to select the one build alternative to evaluate in the EA.

State and federal regulations require the evaluation of a No-Build alternative in an EA. In addition to being a viable alternative, the No-Build Alternative provides a baseline against which to measure and compare the effects of build alternative(s). This baseline helps decision-makers assess what would happen to the environment in the future if nothing were done to address the identified problem.

The No-Build Alternative related to the Tillamook US 101/OR 6 Project would generally retain and would not improve existing transportation facilities in the project area. Maintenance activities on those facilities would be conducted to ensure continued operations of the roadway and bridge.

The figure illustrates the Build Alternative (click on the image for a bigger version). In general, the Build Alternative would:

• Widen the travel lanes by approximately 2 feet and narrow the sidewalks by approximately 2 feet on Main and Pacific Avenues between 1st and 4th Streets
• Extend Pacific Avenue north from the existing Pacific Avenue/1st Street intersection
• Replace the existing 3-lane bridge across Hoquarten Slough with a new 4-lane bridge, which would be up to 5 feet higher than the existing bridge and which would include bike lanes and wider sidewalks
• Reconstruct US 101 approximately 700 feet north of Hoquarten Slough

The following subsections describe the elements of the Build Alternative from south to north in more detail.

• South of 1st Street
  All proposed improvements south of 1st Street under the Build Alternative would occur within existing street right-of-way. The travel lanes on the US 101 couplet (the Main Avenue and Pacific Avenue paired one-way streets) between 1st Street and 4th Street would be widened from approximately 10 feet to approximately 12 feet by narrowing the sidewalks from approximately 12 feet to approximately 10 feet. On-street parking would be generally be maintained on Main and Pacific Avenues. The eastbound approach of the Main Avenue and 3rd Street intersection would be modified in this figure.
• Main Avenue and 1st Street Intersection
  The intersection at Main Avenue and 1st Street would be modified within existing street right-of-way as illustrated in the figure above.
• Pacific Avenue and 1st Street Intersection
  The new northbound leg to the Pacific Avenue and 1st Street intersection would be constructed for northbound US 101 traffic. This intersection and 1st Street between Pacific Avenue and Laurel Avenue would be modified as illustrated in the figure above.
• Between 1st Street and Hoquarten Slough
  The elevation of US 101 north of 1st Street would be raised to match the elevation of the proposed replacement bridge over Hoquarten Slough (described below). Access to and from Front Street from Main Avenue would be maintained.
• Hoquarten Slough Bridge
  The existing 3-lane US 101 bridge across the Hoquarten Slough would be removed under the Build Alternative and a new 4-lane bridge across Hoquarten Slough would be constructed. The bridge would be approximately 84-feet wide. The new bridge would have a center set of piers within Hoquarten Slough. The lowest point of the proposed new bridge’s spans (termed the “low chord”) would be approximately 5 feet higher than the low-chord of the existing bridge at the proposed new bridge’s highest point. In general, traffic across Hoquarten Slough would be maintained during construction.
• US 101 North of Hoquarten Slough
  To tie the US 101 improvements into the existing US 101 alignment, the Build Alternative would reconstruct US 101 from the Hoquarten Slough to approximately 700 feet north of Hoquarten Slough.

More detail on the range of alternatives studied can be found on the Meeting Materials page.

The first phase of the study concluded in January 2010. The current phase will result in an environmental assessment (EA) for the project. Learn more about the project's timeline (click on the timeline to open a printer friendly, larger version). There will be opportunities to get involved along the way.

The intersection of US 101 and OR 6 in Tillamook actually includes four signalized intersections of one way streets: Main Avenue, Pacific Avenue, First Street and Third Street. Main Avenue carries traffic south, Pacific Avenue (US 101) carries traffic north, First Street carries traffic west and Third Street (OR 6) carries traffic east. The City of Tillamook’s Transportation System Plan (TSP) identified safety and operational issues at these intersections including safety for people driving and walking, and congestion. The TSP also identifies localized improvements to address specific issues.

The Tillamook Transportation Refinement Plan (TTRP) evaluated solutions related to pedestrian safety, truck traffic, and parking in the downtown area. As part of these evaluations, the TTRP concurred that vehicle traffic at the intersection would exceed ODOT mobility standards within the 20-year planning period (2025). The TTRP identified and compared improvements to the local system to enhance mobility but did not identify a preferred alternative for the US 101 /OR 6 intersection.

Learn more about the project:

• Alternatives Considered Memo - Revised, December 21, 2009 (PDF, 7.69MB)
• Display Boards of Alternatives - December 15, 2009 (PDF, 733KB)
• Existing Conditions Memorandum - Final, Updated October 30, 2009 (PDF, 1.62MB)
• 2030 Future No-Build Transportation Analysis - Final, Updated October 30, 2009 (PDF, 186KB)
• 2030 Future Build Alternatives Transportation Analysis - Final, Updated October 30, 2009 (PDF, 2.03MB)
• Signal System - May 2009 (PDF, 32KB)
• Environmental Background Report - December 2, 2008 (PDF, 4MB)
• Methods and Assumptions Memorandum - October 17, 2008 (PDF, 199KB)