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January 26, 2018 – A paradigm shift is needed in the design approach of Highway 174 (SR174) in Nevada County. Rather than being viewed simply as a “safety project”, oriented exclusively to motor vehicles, the unique quality of the SR174 corridor warrants that the project be viewed more holistically, as a “placemaking” effort that is context-sensitive and incorporates a variety of design improvements that will enhance multiple functional and aesthetic needs. Simply, a one-size-fits-all engineering design standard, as currently proposed by Caltrans, is not appropriate.

The design of the roadway should be based on four overarching concepts.

First, it is easily observable that the corridor is not uniform in character or function. Some segments are relatively straight, with wide shoulders and long vistas to open, rolling countryside. Other segments contain low-speed curves, narrow shoulders with close roadway cut-and-fill embankments and continuous tree canopies and enclosed views. Some segments are more prone to safety hazards and operational constraints than others. Therefore, the design approach should vary accordingly.

Second, the view from the road is not the only consideration. SR174 is more than simply a transportation corridor. Many people live and work along this roadway, making it the center of a neighborhood. From a neighborhood perspective, there are areas where improvements to the roadway could be beneficial. But building a project that will likely increase vehicular speeds and dramatically alter the character of the neighborhood shows little regard for the residents, businesses, and visitors to the area.

Third, local community engagement in the design process is essential. From a design perspective, it is always true that community engagement results in better design solutions. Residents, businesses and regular visitors have a wealth of knowledge of the values, character and needs of a place. Utilizing this community knowledge makes the work of the design team easier, resulting in a much better project than reliance on statistical data alone can provide.

Fourth, the completed project should realize a greater return on investment for the corridor as a whole, rather than simply improving conditions for motor vehicles. $28 million dollars is a large sum of money for a project of fewer than two miles. For that large expenditure, this project should achieve four primary goals:

  1. create a safer corridor,
  2. provide a variety of multi-modal improvements for pedestrians, bicyclists, equestrians, as well as motor vehicles.
  3. enhance the scenic qualities of the corridor, consistent with recognized scenic highway standards, in order to advance the roadway’s eligibility for designation as a California Scenic Highway, and,
  4. improve the quality of life for SR174 residents, businesses and visitors.

Design Process Considerations

Implementing these four overarching concepts requires that the design process starts with understanding the qualities that make the existing context unique and employs solutions that apply specifically to that context.

  1. Conduct an Existing Conditions Analysis that defines and analyzes the character of the different zones (“Character Zones”) along the roadway. Include a more precise description of the functional, safety and visual aspects of the various Character Zones along with opportunities to enhance adjacent natural and manmade conditions. Utilize the expertise of the local community, Caltrans landscape architects, and outside design consultants, if necessary, to prepare this analysis.
  2. Based in part on the Existing Conditions Analysis, design roadway improvements to be responsive to the changing Character Zones of the roadway. Define which elements should provide design continuity and those elements, including the overall cross-section, that should vary in order to reinforce the episodic character of the roadway and its context.
  3. Develop design alternatives that explore various safety solutions as well as opportunities to provide other functional and aesthetic improvements, consistent with recognized Scenic Roadway standards. Involve citizens and community leaders in selection of a preferred alternative.

Specific Design Program Elements for Consideration

The process to define the specific elements of the design program should include local community workshops, sponsored and supported by Caltrans, where members of the public and local officials can provide design ideas. Following are a few improvements that should be considered.

  1. Provide the necessary functional cross-section of the roadway (12-foot travel lanes and Class 2 bicycle lanes) along the corridor. Vary the design of other elements of the cross-section (such as the Clear Recovery Zone, cut-and-fill embankments, and crossing zones) consistent with recognized scenic roadway standards and responsive to local conditions.
  2. Design the horizontal and vertical alignment to be consistent with recognized scenic highway standards and responsive to local conditions.
  3. Provide wide shoulders and safety turnouts/turnarounds at periodic intervals (for use by motorists and emergency vehicles) where needed and where local conditions permit.
  4. Incorporate a range of traffic-calming and traffic safety measures, as needed, in specific areas, rather than relying primarily on a single uniform design approach as currently proposed.
  5. In addition to Class 2 bicycle lanes, provide facilities for alternative modes of travel.

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  • Extend the existing Narrow Gauge Railroad Trail through the project area for use by pedestrians, bicyclists, and equestrians.
  • Provide safe and convenient crossing facilities at locations identified in the Existing Conditions Analysis.
  1. The SR174 corridor between Grass Valley and Colfax is one of the most historic routes in the state. Protect and strengthen this historic character.
  • Develop and adopt a regulatory, directional and interpretive signage system.
  • Where lighting is needed for safety, utilize ornamental light standards.
  • Protect and celebrate historic features, such as remnants of the Narrow Gauge Railroad and its stations.
  1. Use materials and finishes similar to, and compatible with, materials found in the region and identified in the Existing Conditions Analysis.
  • New plantings should relate to the patterns and species found along the corridor.
  • The design of built structures, walls, fences, poles, barriers, and cut slopes should derive from the design vocabulary found along the corridor.
  1. Place utilities underground or out of view.

A Critical Moment

As one of the first modern highway improvement projects along the SR174 corridor, this project sets a critical precedent. It has the opportunity to enhance a corridor that is already one of the most scenic and historic places in California. Or, by failure to fully understand the context of this corridor and employ sensitive design solutions, it can do permanent damage. The current Caltrans proposal follows the latter course.

Beyond the current project, these design considerations can be used to set guidelines that could be applied to future projects along SR174. Therefore, it is important to take the time, engage all stakeholders and define the design elements (including functional standards) in a thoughtful process. This will likely pay off in more efficient, successful and memorable projects over the long term. One has only to look nearby, to the historic areas of Grass Valley and Nevada City, to see how careful analysis, planning and design have created memorable places and immense value.

Design matters.

Michael Smiley, a Nevada City resident, is an urban design and landscape architect with design experience throughout California and the US. He has led numerous design teams on street, highway, transit, and other transportation-related projects, many within Caltrans jurisdiction.Michael Smiley, a Nevada City resident, is an urban design and landscape architect with design experience throughout California and the US. He has led numerous design teams on street, highway, transit, and other transportation-related projects, many within Caltrans jurisdiction.