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From page 22... ... Evaluating the Performance of Corridors with Roundabouts Chapter 2–Research Approach Page 2-1 CHAPTER 2. RESEARCH APPROACH The major components of the research included the following steps: Establish the need for the project in terms of its place within the body of existing literature and practice. Read the entire page →
From page 23... ... Evaluating the Performance of Corridors with Roundabouts Page 2-2 Chapter 2–Research Approach Tier II – items that apply to many locations (e.g., access management, safety, pedestrian accessibility) Read the entire page →
From page 24... ... Evaluating the Performance of Corridors with Roundabouts Chapter 2–Research Approach Page 2-3 Exhibit 2-1: Known Roundabout Corridors, 2011 (Map) Read the entire page →
From page 25... ... 1 AZ 179 Sedona Coconino AZ 6 3.2 1.9 2 1 Suburbanizing Rural No RIRO and some median breaks No No Signals and TWSC 2008 2011 2 AZ 179 Oak Creek Yavapai AZ 4 1.1 3.6 2 1 Suburbanizing Rural No RIRO and some median breaks No No Signals 2008 3 Cactus Rd Scottsdale Maricopa AZ 3 1 3 2 1 Suburban Residential No TWLTL, many driveways No Some TWSC 2008 4 La Jolla Blvd San Diego San Diego CA 4 0.6 6.7 2 1 Urban Yes Median, many driveways No Some 2 signals, 2 TWSC; TWLTL 2005 and 2008 5 O'Neill Dr San Juan Capistrano Orange CA 4 0.9 4.4 2 1 Suburban Residential No 1 median break, not many driveways No Some New 2003 6 Sienna Pkwy San Juan Capistrano Orange CA 5 1 5 2 1 Suburban Residential No Several median breaks for driveways No Some New 2002 7 Fulton Ave Ripon San Joaquin CA 3 1 3 3 4 1 Suburban No Frontage road, some full access driveways No No New 2006 8 Manzanita Ave Chico Butte CA 3 0.6 5 2 1 Suburban Residential No Full access No No Mixture 2008 or 2009 9 8th Ave Chico Butte CA 3 0.8 3.8 2 1 Suburban Residential No Full access No No Probably TWSC Between 2002 and 2005 10 Avon Rd Avon Eagle CO 5 0.5 10 4 2 Suburban No Two side streets Yes No Unknown 1997 11 Golden Road Golden Jeﬀerson CO 5 1 5 4 2 Suburban No Many mix of RIRO and full access No No Unknown 1998 (one added 2009) 12 William J Read the entire page →
From page 26... ... 40 Reed Market Dr Bend Deschutes OR 5 1.1 4.5 4 2 Suburban No Median and no driveways No Some New facility 2002 41 14th St Bend Deschutes OR 4 1.7 2.4 2 1 Suburban No Many full access side streets No Many Unknown 1999 2005 42 Maple Island Rd Eugene Lane OR 3 0.2 15 2 1 Suburban Retail No No driveways No No New development 2002 43 Via Bella Williamsport Lycoming PA 3 0.3 10 2 1 Urban No No driveways No No Signals Between 2005 and 2008 44 Littlerock Rd Olympia Thurston WA 4 1.1 3.6 2 1 Suburban No Many driveways No No 3 TWSC, 1 signal 2009 2010 45 Grandview Dr University Place Pierce WA 5 1.2 4.2 2 1 Suburban Residential No Some full access side streets No No Stop control 2000 46 Borgen Blvd Gig Harbor Pierce WA 4 1.4 2.9 4 2 Suburban No Mixture of full and RIRO Yes Some Unknown 2000 2007 47 Dike Access Rd Woodland Columbia WA 3 0.2 15 2? 1 Suburban No No driveways Yes No TWSC 2010 2011 48 SR 539 Lynden Whatcom WA 4 6.5 0.6 4 2? Read the entire page →
From page 27... ... Evaluating the Performance of Corridors with Roundabouts Page 2-6 Chapter 2–Research Approach Of these corridors, the research team prioritized the potential sites, based on the team's judgment as to which corridors appeared to have the most promise for positive research outcomes. Foremost, sites were selected if the research team believed they had sufficiently high volumes from which meaningful traffic operations results could be obtained. Read the entire page →
From page 28... ... Evaluating the Performance of Corridors with Roundabouts Chapter 2–Research Approach Page 2-7 Presence/absence of sidewalks and/or bicycle lanes Presence/absence of on street parking With these elements in mind, the research team identified the following nine roundabout corridors from the list as preferred data collection sites: MD 216 in Scaggsville, Maryland La Jolla Boulevard in San Diego, California Old Meridian Street in Carmel, Indiana Spring Mill Road in Carmel, Indiana Borgen Boulevard in Gig Harbor, Washington SR 539 in Whatcom County, Washington Golden Road in Golden, Colorado Avon Road in Avon, Colorado SR 67 in Malta, New York Full field data reports for these nine corridors are included in the NCHRP web only document accompanying this report as Appendices B through J Photos of the corridors taken by the research team are included in the web only document as Appendix K Read the entire page →
From page 29... ... Evaluating the Performance of Corridors with Roundabouts Page 2-8 Chapter 2–Research Approach The research team selected two corridors to use as pilot sites: Maryland State Route 216 (MD 216) in Scaggsville, Maryland, and La Jolla Boulevard in San Diego, California. Read the entire page →
From page 30... ... Evaluating the Performance of Corridors with Roundabouts Chapter 2–Research Approach Page 2-9 GPS Technology, in the form of an in vehicle data logger, continuously recorded the speed and position of the vehicle as it traveled along the corridor (in 1 second intervals) Read the entire page →
From page 31... ... Evaluating the Performance of Corridors with Roundabouts Page 2-10 Chapter 2–Research Approach The corridor travel times, estimated through a combination of both approaches and the travel time data, were further supplemented with other data collection technologies: Tally Sheets: Many of the necessary data collected as a part of a roundabout corridor evaluation can be quickly gathered in the ﬁeld using tally sheets from a good vantage point, including delay and queue measurements. The research team applied video to some extent to provide a permanent record of conditions during the ﬁeld study and to collect data items diﬃcult to observe in the ﬁeld in real time; however, tally sheets improved the economy of oﬃce data extraction for readily observed measures. Read the entire page →
From page 32... ... Evaluating the Performance of Corridors with Roundabouts Chapter 2–Research Approach Page 2-11 Lidar: The research team also wanted to directly collect a selection of speed data at key locations for comparison to the speed data obtained from the other data collection methods. To fulfill that need, the researchers used a handheld lidar gun to measure speeds, which were recorded manually on tally sheets. Read the entire page →
From page 33... ... Evaluating the Performance of Corridors with Roundabouts Page 2-12 Chapter 2–Research Approach A two phase data collection schedule was not necessary; there was sufficient time within a single three day trip to collect the needed data at a study site. Extending the study period to three days provided the time needed to take pictures and compile field notes in addition to the other needed data collection. Read the entire page →
From page 34... ... Evaluating the Performance of Corridors with Roundabouts Chapter 2–Research Approach Page 2-13 of (at least) one 12 hour period on video over two consecutive days for each roundabout along the corridor. Read the entire page →
From page 35... ... Evaluating the Performance of Corridors with Roundabouts Page 2-14 Chapter 2–Research Approach 4. Arrival paerns (platooning) Read the entire page →
From page 36... ... Evaluating the Performance of Corridors with Roundabouts Chapter 2–Research Approach Page 2-15 Exhibit 2-6: Work Schedule for Single-Site Data Collection 7-9 9-11 11-1 1-3 3-5 5-7 6-7 7-9 9-11 11-1 1-3 3-5 5-7 7-9 9-11 11-1 Site Characteristics (Tally) 1,2 1 1 Corridor travel time through (GPS) Read the entire page →
From page 37... ... Eva lu a tin g th e Pe rfo rm a n c e o f C o rrid o rs w ith R o u n d a b o u ts Page 2-16 Chapter 2–Research Approach Exh ibit 2-7: W ork Schedule for D ouble-Site D ata C ollection Day Data Item 1-3 3-5 5-7 7-8 8-10 6-7 7-9 9-11 11-1 1-3 3-5 5-7 7-8 8-10 6-7 7-9 9-11 11-1 1-3 3-5 5-7 Site Characteristics (Tally) 1,2 1 1 Corridor travel time through (GPS) Read the entire page →
From page 38... ... Evaluating the Performance of Corridors with Roundabouts Chapter 2–Research Approach Page 2-17 2.4. SITE CHARACTERISTICS SUMMARY As discussed previously (Section 2.2) Read the entire page →
From page 39... ... Evaluating the Performance of Corridors with Roundabouts Page 2-18 Chapter 2–Research Approach part of travel time runs involving left turns, but based on the team's observations they were generally similar to the arterial approach delays. Exhibits 2 8, 2 9, and 2 10 present a summary of characteristics of the nine study corridors. Read the entire page →
From page 40... ... Evaluating the Performance of Corridors with Roundabouts Chapter 2–Research Approach Page 2-19 M ed ia n D riv ew ay s O nSt re et P ar ki ng Si de w al ks Cr os sw al ks Pe ak -H ou r Pe de st ria n Vo lu m es (I nt er se ct io n To ta ls ) Bi ke L an es MD 216 Raised 0 No Yes Yes Not counted No La Jolla Boulevard Raised 17 Yes Yes Yes 10 to 60 Yes Spring Mill Road Mostly none 33 No Varies Yes 0 to 12 No Old Meridian Street Mostly raised 22 Yes Yes Yes 0 to 10 No Borgen Boulevard Varies 8 No Yes Yes 0 to 4 Yes SR 539 Cable 67 No No Yes 0 to 8 No Golden Road Raised with openings 19 No Yes Yes 4 to 14 No Avon Road Raised, 1 opening 1 No Yes Yes 0 to 28 No SR 67 Raised, none 22 No Yes Yes 0 to 24 No Exhibit 2-9: Access Management and Pedestrian/Bicycle Characteristics of Data Collection Sites Read the entire page →
From page 41... ... Evaluating the Performance of Corridors with Roundabouts Page 2-20 Chapter 2–Research Approach PeakHour Traffic Volumes (Arterial) PeakHour Traffic Volumes (Side Streets) Read the entire page →
From page 42... ... Evaluating the Performance of Corridors with Roundabouts Chapter 2–Research Approach Page 2-21 2.5. CORRIDOR OWNER INTERVIEWS The research team held interviews with the owners of nine roundabout corridors at which field data was collected for this project. Read the entire page →
From page 43... ... Evaluating the Performance of Corridors with Roundabouts Page 2-22 Chapter 2–Research Approach two lane roundabouts for the two ramp terminal intersections. SHA believed roundabouts offered a number of benefits, including reduced delay, and traffic forecasts indicated two lane roundabouts would sufficiently serve future demand. Read the entire page →
From page 44... ... Evaluating the Performance of Corridors with Roundabouts Chapter 2–Research Approach Page 2-23 addition, neighborhood groups were concerned over the potential for diversion of traffic into adjacent neighborhoods. The City of San Diego engaged Dan Burden to conduct some design charees to explore ways to enhance the corridor, and Michael Wallwork provided concept designs for roundabouts at each of the key intersections. Read the entire page →
From page 45... ... Evaluating the Performance of Corridors with Roundabouts Page 2-24 Chapter 2–Research Approach A project like this has constant challenges. "If you think the project is good, stick with it." A toolbox with factual statistics is helpful in communication, particularly when discussing issues related to pedestrian, bicyclist, and elderly issues. Read the entire page →
From page 46... ... Evaluating the Performance of Corridors with Roundabouts Chapter 2–Research Approach Page 2-25 The City is generally pleased with the Spring Mill Road corridor and would change relatively lile if it were constructed again. Although the traffic forecasts did not accurately reflect near term conditions, they also assumed US 31 improvements would have been in place. Read the entire page →
From page 47... ... Evaluating the Performance of Corridors with Roundabouts Page 2-26 Chapter 2–Research Approach Old Meridian Street/Carmel Drive: Volumes will likely decrease at this intersection because the signal at US 31/Carmel Drive will be replaced with an overpass (without an interchange) Read the entire page →
From page 48... ... Evaluating the Performance of Corridors with Roundabouts Chapter 2–Research Approach Page 2-27 issues with large trucks off tracking over curbs at the 112th Street/Peacock Hill Avenue roundabout. This roundabout is smaller than others on the corridor, and was built in a location with ROW constraints. Read the entire page →
From page 49... ... Evaluating the Performance of Corridors with Roundabouts Page 2-28 Chapter 2–Research Approach roundabouts. Staff indicated they would likely use simulation for visualization purposes today, although likely VISSIM rather than Paramics. Read the entire page →
From page 50... ... Evaluating the Performance of Corridors with Roundabouts Chapter 2–Research Approach Page 2-29 and the roundabouts was a more effective strategy for the corridor than either would have been by itself, and WSDOT hopes to use these techniques in combination again. The District remains opposed to traffic signals on high speed roadways; the public is pleased with the performance of SR 539 and supportive of roundabouts on high speed roadways. Read the entire page →
From page 51... ... Evaluating the Performance of Corridors with Roundabouts Page 2-30 Chapter 2–Research Approach A consultant for the City conducted traffic modeling of two scenarios on the corridor: one with traffic signal improvements and one with roundabouts. Both performed well operationally and were viable. Read the entire page →
From page 52... ... Evaluating the Performance of Corridors with Roundabouts Chapter 2–Research Approach Page 2-31 corridors have also been built nearby on William J Post Boulevard and Edwards Access Road, and a corridor is planned nearby in Eagle, Colorado. Read the entire page →
From page 53... ... Evaluating the Performance of Corridors with Roundabouts Page 2-32 Chapter 2–Research Approach the development and/or current operation of the SR 67 roundabout corridor. The individuals were: Mark Kennedy, Regional Traffic Engineer, NYSDOT Region 1 James Boni, Assistant to the Regional Director, NYSDOT Region 1 Howard McCulloch, Statewide Roundabout Design Specialist, NYSDOT NYSDOT staff shared the history of the corridor and changes that have taken place since it opened. Read the entire page →
From page 54... ... Evaluating the Performance of Corridors with Roundabouts Chapter 2–Research Approach Page 2-33 The mayor of Malta and the public were generally supportive of the concept for roundabouts on SR 67, and Region 1 staff chose to move forward with the roundabout corridor plan. The first five roundabouts opened in 2006 2007. Read the entire page →
From page 55... ... Evaluating the Performance of Corridors with Roundabouts Page 2-34 Chapter 2–Research Approach 2.6. CONCLUSION The research team prepared a CCD to aid practitioners with objective and comprehensive comparisons of corridor alternatives. Read the entire page →

From page 22...

... Evaluating the Performance of Corridors with Roundabouts Chapter 2–Research Approach Page 2-1 CHAPTER 2. RESEARCH APPROACH The major components of the research included the following steps: Establish the need for the project in terms of its place within the body of existing literature and practice.