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Road Alignment & Configuration

Fitting Road to Landscape - Horizontal Alignment

In limited areas where realignment may be feasible, realign the roadin a curvilinear manner so views of the surrounding landscape will

be enhanced for highway travelers. These subtle meanders or curvesin horizontal alignment will allow the road to better fit thelandscape. All horizontal curves willmeet or exceed AASHTO standards.For the most part, this curvilinearrealignment can occur within theright-of-way established by the AccessControl and Corridor Preservationproject.

Avoid long, straight stretches of roadwhere the road becomes the dominantvisual element. Long, straight sectionsare also conducive to boredom and

increased travel speeds. Use the design of the road to enhance

views of significant landscape featuresand vistas of water bodies, valleys,mountain ranges, etc. by altering theorientation of the road so it isdirected toward the landscape feature.Conversely, care should be taken tonot block scenic views and vistas.

Avoid using curves separatedby long, straight tangents.Instead of tangents, incorporatespiral or transition curves to

achieve a continuous,curvilinear road that moldswith the rolling terrainfeatures.

Horizonatal alignment should react toexisting landscape features.

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Avoid using curves separated by long, straight tangents. Instead oftangents, incorporate spirals or transition curves to achieve acontinuous, curvilinear road that molds with the rolling terrainfeatures.

Explore using a reddish aggregate for travelway pavement similar tothat already in place north of Elmo. The reddish aggregate helpscreate a distinctive visual appearance for the road within theReservation. Differentiation of the travelway from the shoulder will

help to decrease the scale and visual impact of the road.

Fitting Road to Landscape - Vertical Alignment

Design roads so they respond to the landscape, blend in with theenvironment, and follow contours to avoid large cuts and fills.

Develop vertical curvature that reflects the rolling movement of thelandscape. All vertical curve data will meet or exceed AASHTOstandards.

Wherever possible, the new roadbed should be close to the existingground to keep from creating a dam-like effect that splits the

landscape. Cut and fill slopes should be kept to a minimum, withedges rounded to match the existing landforms. Surfaces of gradedslopes should be left with a rough texture to promote vegetativegrowth.

Where applicable, remove the existing road structure and lower thenew roadbed to an elevation more in keeping with the existinggrade in areas where the finished grade of the existing road isconsiderably higher than the surrounding ground plane. This willprevent the new road from creating a dam-like effect that splits thelandscape, disrupts normal hydrologic flow under the road, and is abarrier for wildlife movement. In areas where wildlife crossings arerequired, however, the road may need to be raised instead.

This is an example of how the transitionbetween cut /fill slopes and existinglandforms should be handled to insure

continuity.

In Pablo, the road cross-section is reducedto allow for berms planted with nativepines separating the roads.