To: Honorable Mayor and Members of Town Council
Through: David L. Corliss, Town Manager
From: Daniel Sailer, Director of Public Works
Title
Discussion/Direction: Fifth Street Improvements Project - Recommended Design
Body
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Executive Summary
The purpose of this agenda item is to seek Town Council approval of the recommended concept design of the Fifth Street Improvements Project. The Fifth Street Improvements Project has three primary objectives; increase multi-modal use and pedestrian safety, improve safety for the traveling public, and improve levels of service (LOS). These objectives were designed around the elements valued by the community. The project team has assessed six different alternatives, each involving different combinations of intersection improvements and lane configuration/layouts that meet project objectives.
Recommended Alternative
The recommended alternative is a four-lane design (Attachment A) between Founders and Woodlands including a roundabout at Woodlands Boulevard and a traditional signal at Valley Drive. This recommendation is supported by staff, stakeholders and the community.
A community centric process ensures that the recommended project improvements have incorporated community and stakeholder needs/desires.
The community and stakeholders desire a four-lane configuration
• 70% of feedback received indicated a four-lane configuration was preferable
• Improved utility for emergency services
A community concern regarding high speeds (22% of feedback), is addressed by:
• Roundabout at Woodlands may offer speed calming/reduction benefits
• Recommended design includes raised median, which may offer speed calming/reduction benefits
• Roadway design changes may offer speed calming/reduction benefits
• Posted speed limit reduction from 45 to 35 MPH.
The remainder of the memo describes the process implemented and shares a summary of the community feedback received.
Discussion
Approach to Finalize Recommendation
In order to finalize a design recommendation that meets project objectives and addresses community needs, a sequential process was implemented. The approach taken was iterative and ensures that the recommendation is supported at the staff and community level. The process included staff evaluation, staff recommendation, and community feedback.
Staff Evaluation
Multiple design alternatives were developed that meet project objectives
Four-lanes between Founders and Woodlands:
• 2A: Traditional signal at Woodlands and continuous Green-T (CGT) at Valley
• 2B: Roundabout at Woodlands and Valley
• 2C: Roundabout at Woodlands and traditional signal at Valley (Attachment A)
Three-lanes:
• 1A: Traditional signal at Woodlands and continuous Green-T (CGT) at Valley
• 1B: Roundabout at Woodlands and Valley
• 1C: Roundabout at Woodlands and CGT at Valley (Attachment B)
To compare alternatives of varying size and scope, an evaluation matrix was developed and scoring criteria was established for each category of the matrix using the Town of Castle Rock Public Work’s vision of elevating value as the foundation of the comparison. Each design was scored within the matrix and results were reviewed and confirmed with department staff.
At the end of the staff evaluation process the two highest scoring alternatives were selected to continue through the recommendation process; Alternative 2C (hereafter referred to as the Four- lane alternative), and Alternative 1C (hereafter referred to as the Three-lane alternative).
Four-lane Alternative - Roundabout and Traditional Signal (Attachment A)
A four-lane layout with a roundabout at Woodlands Boulevard and traditional signal at Valley Drive scored highest of the four-lane alternatives evaluated. This design improves safety for the traveling public, increases reliability (decreasing congestion) and will decrease downtime during future maintenance operations. The general configuration of the proposed improvements is illustrated below:
Figure 1: Four-lane section (Woodlands to Founders)
This alternative presented various advantages and disadvantages (summarized below).
Figure 2: Four-lane Alternative Advantages/Disadvantages
Three-lane Alternative - Roundabout and Traditional Signal (Attachment B)
A three-lane layout with a roundabout at Woodlands Boulevard and a traditional signal at Valley Drive scored highest of the three-lane alternatives evaluated. This design improves safety for the traveling public, has a relatively lower environmental impact, and lower cost. The general configuration of the proposed improvements is illustrated below:
Figure 3: Three-lane section (Woodlands to Founders)
This alternative presented various advantages and disadvantages (summarized below).
Figure 4: Three-lane Alternative Advantages/Disadvantages
Staff Recommendation
Upon completion of evaluations, the project team outlined recommendations for both the three and four-lane alternatives as they were both highly desirable when considering multiple elements of value. The stronger recommendation was for the four-lane alternative.
It was determined that community input and feedback would be an important deciding factor to validate staff recommendation.
Community Feedback
Community feedback was essential to the project for determining the recommended lane layout, thus both alternative designs were presented to the community at a public open house. At the open house feedback was elicited from members of the community to determine which was preferred.
Of the thirty-six respondents (number of submitted feedback forms), twenty-one preferred the 4- lane as opposed to nine in favor of the 3-lane as shown in Figure 3 below.
Figure 5: Community Alternative Preference
Community feedback supported a recommendation for the four-lane alternative design (Attachment A).
Pedestrian Facility Concepts
The objective of improving pedestrian connectivity, safety and utility with the project had originally resulted in a design that included eight foot sidewalks and on-street bike lanes. Upon evaluation of community feedback from the open house, the project team was challenged with assessing the value of the on-street bike lanes. Almost half of the respondents indicated that walking and biking/cycling facilities were important aspects of the project. Some respondents (2) in this group suggested that on-street bike lanes be eliminated as they would have less value to the cyclist due to vehicle speed as well as roadway grades (steepness).
Working with the traffic division, the project team determined what changes should be evaluated to address the community feedback and provide a context sensitive design for the pedestrian facilities (specifically cyclists).
A design that eliminated the proposed on-street bike lanes while expanding the sidewalks to twelve-foot multi-use side paths (Figure 6) was thus evaluated and compared with the design that included an eight-foot sidewalk with an on-street bike lane (Figure 7).
Upon further analysis, it was determined that the on-street bike lanes (with an eight-foot sidewalk - Figure 6) are preferable in order to offer both pedestrians and bicyclists the best combination of utility and comfort. This decision is also consistent with current transportation planning documents including the Transportation Master Plan, that has identified the need for on-street bicycle lanes on this portion of Fifth Street.
Figure 6: Multi-use Side Path
Figure 7: On-street Bike Lanes
Staff Recommendation
Staff recommends that Council provide staff direction to continue design development of the Fifth Street Improvements project based on the recommended concept/layout.
Proposed Motion
“I move to direct staff to continue design development of the Fifth Street Improvements project as recommended.”
Attachments
Attachment A: Four-lane Alternative Design
Attachment B: Three-lane Alternative Design