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From page 349... ... 14-1 Contents 14-2 14.1 General Illumination Considerations 14-2 14.1.1 Lighting Policies 14-3 14.1.2 Dark Sky Principles 14-3 14.2 Lighting Levels 14-3 14.2.1 Roundabouts on Streets with Continuous Lighting 14-4 14.2.2 Isolated Roundabouts (No Continuous Lighting on Any Approach) 14-5 14.2.3 Crosswalk Lighting 14-5 14.2.4 Transition Lighting 14-6 14.3 Illumination Equipment Type and Location 14-8 14.4 Landscaping 14-9 14.4.1 Landscaping Objectives 14-10 14.4.2 Central Island Landscaping 14-12 14.4.3 Median and Approach Landscaping 14-14 14.4.4 Sidewalk or Path Buffers 14-14 14.5 Art and Other Fixed Objects 14-18 14.6 References This chapter discusses illumination, landscaping, and artwork at roundabouts. Read the entire page →
From page 350... ... 14-2 Guide for Roundabouts 14.1 General Illumination Considerations As with any intersection lighting, roundabout lighting makes the roundabout visible from a distance and makes vehicular and non-motorized traffic more visible in conflict areas. Motor vehicles have headlights and taillights to improve their visibility at night. Read the entire page →
From page 351... ... Illumination, Landscaping, and Artwork 14-3 14.1.2 Dark Sky Principles The International Dark-Sky Association and IES have jointly published five principles for responsible outdoor lighting (9) Read the entire page →
From page 352... ... 14-4 Guide for Roundabouts • If the roundabout is paved with PCC, Exhibit 14.2 can help determine the appropriate horizontal illuminance level for the roundabout. If an approach has a higher lighting level than IES recommends for that type of facility, the roundabout illuminance level should be equal to the sum of the intersecting roadways. Read the entire page →
From page 353... ... Illumination, Landscaping, and Artwork 14-5 and the mounting height, lumen level, and distribution type of the selected luminaires. A casespecific design will be necessary to determine the applicable lighting configuration. Read the entire page →
From page 354... ... 14-6 Guide for Roundabouts with increased distance from the roundabout. Values in the exhibit may be interpolated as needed or rounded up to the next highest value. Read the entire page →
From page 355... ... Illumination, Landscaping, and Artwork 14-7 Transition Zone Length (ft) Downstream Posted Speed Zone 1 (70%) Read the entire page →
From page 356... ... 14-8 Guide for Roundabouts The ability to provide adequate visibility at a roundabout depends largely on the illumination pole locations. Roundabout lighting can be achieved by installing lighting within the central island or around the perimeter of the intersection. Read the entire page →
From page 357... ... Illumination, Landscaping, and Artwork 14-9 Discussions about the type and quantity of landscaping or other material to incorporate into a roundabout design, maintenance considerations, and the available planting zones best occur early in planning and design. Choosing between soft landscaping and hardscaping may affect funding and maintenance agreements, and discussions about the type or extent of possible treatments are appropriate during ICE activities. Read the entire page →
From page 358... ... 14-10 Guide for Roundabouts • Help pedestrians who are blind or have low vision locate sidewalks and crosswalks. The buffer strip beside a sidewalk or walking path is an essential wayfinding component for pedestrians who are blind or have low vision. Read the entire page →
From page 359... ... Illumination, Landscaping, and Artwork 14-11 roundabout and the required sight triangles, as described in Chapter 9: Geometric Design Process and Performance Checks. Exhibit 14.10 illustrates an example of central island landscaping. Read the entire page →
From page 360... ... 14-12 Guide for Roundabouts the guidance for transverse slopes in the AASHTO Roadside Design Guide) Read the entire page →
From page 361... ... SOURCE: Larimer County, Colorado. Exhibit 14.12. Read the entire page →
From page 362... ... 14-14 Guide for Roundabouts are determining factors when assessing whether to provide landscaping within the splitter islands. Generally, low-growing landscaping is recommended within sight triangles on either side of the pedestrian crossing and between the crossing and the circulatory roadway. Read the entire page →
From page 363... ... Illumination, Landscaping, and Artwork 14-15 SOURCE: Fred Wismer. Exhibit 14.16. Read the entire page →
From page 364... ... 14-16 Guide for Roundabouts LOCATION: Gannett Avenue/Rittenhouse Street, Des Moines, Iowa. SOURCE: Lee Rodegerdts. Read the entire page →
From page 365... ... Illumination, Landscaping, and Artwork 14-17 affect the drivers circulating the roundabout. For example, fountains on the central island of a roundabout may be feasible, but maintenance, the potential for leaks, and the range of spray under windy conditions must be considered. Read the entire page →
From page 366... ... 14-18 Guide for Roundabouts 14.6 References 1. Recommended Practice for Design and Maintenance of Roadway and Parking Facility Lighting. Read the entire page →

From page 349...

... 14-1 Contents 14-2 14.1 General Illumination Considerations 14-2 14.1.1 Lighting Policies 14-3 14.1.2 Dark Sky Principles 14-3 14.2 Lighting Levels 14-3 14.2.1 Roundabouts on Streets with Continuous Lighting 14-4 14.2.2 Isolated Roundabouts (No Continuous Lighting on Any Approach) 14-5 14.2.3 Crosswalk Lighting 14-5 14.2.4 Transition Lighting 14-6 14.3 Illumination Equipment Type and Location 14-8 14.4 Landscaping 14-9 14.4.1 Landscaping Objectives 14-10 14.4.2 Central Island Landscaping 14-12 14.4.3 Median and Approach Landscaping 14-14 14.4.4 Sidewalk or Path Buffers 14-14 14.5 Art and Other Fixed Objects 14-18 14.6 References This chapter discusses illumination, landscaping, and artwork at roundabouts.