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    RECENT E-MAIL NEWS

    From: Rahmi Akcelik To: ITETRAFFIC@LIST.ITE.OR
    Subject: Roundabout Lane-Use Control Markings (PavementArrows)
    Date sent: Thurs, 03 Oct 2002 10:41:15-0500


    Dear Colleagues
    This is further to my message dated 16 September 2002 regarding Roundabout Lane-Use Control Markings (Pavement Arrows). An Australian colleague brought to my attention that, in their jurisdiction, there were a couple of reported instances of the right turn arrow in the right lane (as for the LEFT turn arrow in the LEFT lane in the USA) causing a vehicle to turn the wrong way round the roundabout. They have advised that the lane arrows should NOT be positioned close to the roundabout yield line. By having them further upstream on the approach to the intersection, they consider that the lane arrows can be taken as the movement to be made at the intersection (the roundabout) rather than the movement to be made at the intersection of the approach with the circulating carriageway. Their MUTCD (2001) recommends that "The first pavement arrow should be spaced at a distance of 15-30 m (50-100 ft) from the holding line." (see the attached document). It is interesting to observe how the use of pavement arrows changed over the years in Australia since the introduction of roundabouts. The 1994 edition of the Australian MUTCD, AS 1742.2, page 65 (Standards Australia) stated that "Pavement arrows are not normally placed in the entry lanes on the approach to single and two-lane roundabouts." and the associated Fig. 2.20 showed a two-lane roundabout without pavement arrows. Similarly the AUSTROADS Guide to Traffic Engineering Practice Part 6 (1993) states "In general, lane direction arrows are not necessary in the entry lanes to the approach to single and two-lane roundabouts.". However, the 1997 Amendment to the Australian MUTCD, AS 1742.2, page 65 states that "Pavement arrows are not normally marked on single lane entries to roundabouts. Where a roundabout has two or more lanes on an entry, pavement arrows are marked to show movements permitted from each entry lane." and the amended Fig. 2.20 shows a two-lane roundabout with pavement arrows. It is also interesting to note the statement by FHWA Roundabout Informational Guide (Section 7.1.2.4, last para.): "... given the unfamiliarity of roundabouts to drivers in the United States at this time, it is recommended that double-lane roundabouts be designed to avoid the use of lane-use control signs wherever possible, at least until drivers become more accustomed to driving roundabouts." and the Section 7.2.2.3 suggests the same regarding pavement arrows. This concurs with the progress in Australia from minimal use of pavement markings towards judicious use of pavement arrows (as well as circulating road lane markings). The placing of approach lane-use (pavement) arrows a little upstream of the yield line as suggested above may be a useful solution to the problem of misunderstanding by drivers.
    Best wishes
    Rahmi Akcelik
    Adjunct Professor, Monash University
    Director, Akcelik & Associates Pty Ltd
    ABN 79 088 889 687
    Email: rahmi@akcelik.com.au
    Web page: www.aatraffic.com
    Phone: +61 3 9857 9351, Fax: +61 3 9857 5397
    Mail: P O Box 1075 G, Greythorn Vic 3104, Australia



    From: Batson,Scott < Scott.Batson@PDXTRANS.ORG
    To: geno@ce.ksu.edu
    Subject: Re: Traffic Calming (Highest Volume for Traffic Circle)
    Date sent: Fri, 04 Oct 2002 10:08:43-0700

    Traffic circles are not constructed on collector streets in Portland. For any street above Local Service for which a circular intersection treatment was considered, a modern roundabout design - compact urban or larger - would be used.
    The FHWA guideline provide data on roundabout capacity.
    http://www.tfhrc.gov/safety/00068.htm
    Seattle does not require anyone to go around its traffic circles - anyone can turn left in front of them. Portland requires counter clockwise movement around traffic circles, but recognizes the occasional WB-40 or larger may need to turn left in front of the circle. Our pathway around the circle is a standard 13 ft wide and we often increase the corner radii to achieve the maximum circle diameter for maximum deflection and slowing. Parking is typically only prohibited in the first 40 feet of curb near the traffic circle on the through street. cross streets are usually already stop controlled before construction and are left that way after. The design vehicle for our traffic circles is a transit or school bus, which typically are traveling through and not turning left. Portland uses a dual height curb, supposedly mountable, but it is slated for redesign to more closely match roundabout standards. Portland also does not use volume in its definitions of street classification. Portland has local service streets with volumes of 2,000-5,000 vpd and traffic circles (link ends in .HTM).
    http://www.trans.ci.portland.or.us/TrafficCalming/Evaluations/LOCAL/GLAD2639 FINAL.HTM
    Commentary: on streets with such volume, what percent of traffic is actually turning to the local side streets and delaying through traffic now? Whenever someone raises concerns to a proposed solution, I always like to go back to comparing the solution to the current situation. Most important is to ask what is gained and what is lost with the change and to weigh those results against each other. If you have a collision problem at an intersection with such volumes, a traffic circle or roundabout will significantly alter the severity of such collisions. if the problem is through street speed, circles would need to be constructed at about 400-500 ft intervals to achieve substantial slowing. the modern roadway bump/hump is much more flexible in its application to speed control for close to 1/10th the cost to the public, as compared to traffic circles. Also, you can be sure that an object in the roadway will be struck. Scott Batson, PE
    Senior Engineering Associate
    Portland Office of Transportation
    E-mail: Scott.Batson@pdxtrans.org

    Visit our Traffic Calming Web Site at:
    http://www.trans.ci.portland.or.us/TrafficCalming/default.htm


    From: Jim Schroll;traffic1@toad.net
    To: geno@ce.ksu.edu
    Subject: Re: Traffic Calming (Residential Street Narrowing)
    Date sent: Fri, 13 Sep 2002 12:07PM

    Gene,
    Sorry about the delay in responding. People who aren't happy with us get much faster responses than the few of you who actually write to tell us that they are favorably impressed! The County does have a few roundabouts - the Lothian roundabout is in Anne Arundel County (although it was designed and is maintained by the State). We have one that was built by a developer, one built as part of a County road project, and one which we (Traffic Engineering) built to resolve operational problems at an intersection. In the last case, the intersection had a lot of left turns in all directions. The initial request was for a 4-way STOP, and we considered that until we watched the intersection operate. It wasn't unusual for drivers who had the right-of-way to stop and wave others through the existing STOP signs. We didn't think that adding two more was going to improve the situation much. We also considered a signal briefly, but felt that it would be out of character at the edge of this particular community. There was enough right-of-way to allow a roundabout, and we worked with the affected communities to develop consent. It works much better than the old intersection and the residents like it. There is an elementary school in this community, and a lot of school buses must use the intersection. There was some concern about bumping the bus riders around if the buses needed to go over the truck apron. We "designed" the roundabout in the parking lot of an out-of-business shopping center - we laid out a circle and kept changing the dimensions until we had the smallest one that an average bus driver could negotiate without hitting the apron. The result is an outside diameter of about 100 feet. There are also two roundabouts in the city of Annapolis (which is located in the County but takes care of their own roads and traffic). One is relatively new and was the subject of a great deal of controversy during its planning. The other is at the foot of Main Street, in about as prominent a location as you could find, and it's been there for years and years. It was always known as a "circle" even though it operates as a roundabout (all entering legs must yield). Once we started reminding people that they had used one of these "new" roundabouts for years, some of the opposition lessened. Early in their efforts to promote roundabouts, the State even took videos of it to show to other communities. We also use small intersection circles for speed control. These are placed within existing intersections with no road widening. We allow left turns to be made either in front or by going around the circle (we avoid placing them where school buses must make left turns). The side streets are still controlled by STOP signs, although we move the stop bar back to facilitate through movements on the main street. We were concerned about how they would work initially, and then concerned again when we built our first roundabouts, but they have worked well and without accidents. Based on watching them, it seems that drivers tend to turn left in front of the circle if they don't see any other vehicles in the vicinity. If they see another vehicle (on any of the approaches), they tend to go 270 degrees around the circle. I think that their travel paths are probably indistinguishable from those at an intersection without a circle (most left turns cut the corner a bit unless there is a car on the side street). While we're not in Scott Batson's league (no pictures or videos yet), you can find our Neighborhood Traffic Control Guidelines at www.aadpw.org/tpolicy.htm . Thanks for your kind comments. I'd be glad to answer any questions you might have.
    Jim Schroll
    Anne Arundel County, MD
    410-222-7331


    From: Barry Crown
    To: geno@ce.ksu.edu
    Subject: Roundabouts and Volume
    Date sent: Sat, 07 Sep 2002

    Gene,
    There is no simple 'rule of thumb' for the capacity of a roundabout. Overall capacity for a roundabout intersection is a misleading concept. You can have the capacity of an approach against circulating volumes. Suppose a 4 leg roundabout has 1000 vph on each approach in the AM peak hour and that 100% make a right turn. The circulating volumes will be zero past each approach so the capacity of each entry will be very high. Suppose during the PM peak this traffic makes the return journey, then you have 1000 on each approach with 100% making a left turn. This gives a circulating volume of 2000 vph past each approach making the capacity of each entry VERY small. What is the roundabout? Obviously this is the two extremes that never happen, but this effect is still very large on real roundabout traffic distributions. Sidra considerably overestimates capacity when circulating volumes are low and considerably underestimates capacity at high circulating volumes. You must plot the capacity curve against a wide range of circulating volumes to test the differences. This is very easy with Rodel as it is a straight line curve needing only two points. It is tedious with Sidra as it i a curve and you need a lot of points to plot it. You need to work harder at working less.
    Barry



    From: BARNETT Brian <bbarnett@ci.springfield.or.us>
    To: geno@ce.ksu.edu
    Copies to: MAYES Kristi <kmayes@ci.springfield.or.us>
    Subject: Re: itetraffic roundabouts
    Date sent: Thu, 12 Apr 2001 08:11:00 -0700

    Gene,
    We have one roundabout designed and out to bid for construction in a few weeks with city funds and three that are proposed by a developer and will be built this summer. The triplet of roundabouts will be funded 1/3 by city and 2/3 by developer/land owner since it is a new road link. Please contact me or Kristi if you need additional info.

    Brian F. Barnett, P.E.
    Traffic Engineer
    City of Springfield
    225 Fifth Street
    Springfield, OR 97477
    Telephone: 541-726-3681
    Facsimile: 541-736-1021
    Email: bbarnett@ci.springfield.or.us
    Web:
    www.ci.springfield.or.us


    Design Specifications for the above mentioned Roundabouts

    From: BARNETT Brian <bbarnett@ci.springfield.or.us>
    To: geno@ce.ksu.edu
    Copies to: MAYES Kristi <kmayes@ci.springfield.or.us>
    Subject: Re: itetraffic roundabouts
    Date sent: Thu, 12 Apr 2001 14:27:00 -0700

    Gene,
    Single circulating lane with truck apron, replaces through/right and left turn lanes on 3 approach legs. One leg local, one leg collector, two legs minor arterial (they really act like collectors) residential area near a high school and middle school.

    Prior control: Two Way Stop sign.

    All concrete (not just the truck apron), extensive landscaping, new lighting, incorporates bike lanes from 3 legs in to approach to r-bout.

    Design vehicle = WB-50 but WB-67 will be able to traverse with out damaging landscaping or signs.

    Project purpose: signal not warranted for a long time; concern for pedestrian crossing, major leg not stopped left turn delay and major leg stopped delay (the major flow is on the east and north legs); demonstration of roundabout.

    Kristi, please email condensed drawing to Gene and add any comments you like.

    Brian F. Barnett, P.E.
    Traffic Engineer
    City of Springfield
    225 Fifth Street
    Springfield, OR 97477
    Telephone: 541-726-3681
    Facsimile: 541-736-1021
    Email: bbarnett@ci.springfield.or.us
    Web: www.ci.springfield.or.us


    From: "Mark Lutjeharms" <mlutj@schemmer.com>
    To: <geno@ce.ksu.edu>
    Subject: roundabouts
    Date sent: Thu, 12 Apr 2001 07:37:38 -0500

    There are a few roundabouts in the planning stages in Lincoln, Nebraska.

    One of them (33rd Street/Sheridan Boulevard) is through the design phase and is scheduled for construction to begin later this Spring.

    Our company is currently in the design phase of two others (49th/Francis, West Fletcher Avenue). If you want further information, a gentleman by the name of Virendra Singh (City of Lincoln Public Works Department, Engineering Services Division) is involved with all of them. His number is (402) - 441- 7835.

    Mark E. Lutjeharms, P.E.
    Manager, Traffic Engineering

    The Schemmer Associates Inc.
    Architects-Engineers

    1919 South 40th Street, Suite 302
    Lincoln, NE 68506-5248
    402-488-2500
    402-488-3221 (fax)


    From: rlewis@ci.bend.or.us
    Subject: Re: itetraffic roundabouts
    To: geno@ksu.edu
    Date sent: Thu, 12 Apr 2001 08:22:14 -0700


    Hi Gene,

    Here in Bend Oregon, we have a policy recently handed down by the City Council to examine the feasibility of a roundabout every time we are considering a traffic signal. And if the roundabout is proven to be feasible, that will be the preferencial treatment to start with. We have recently passed a development agreement with several developers who have been given permission to build their subdivisions as long as they build several intersection improvements. They have chosen roundabouts and have constructed one already and are beginning design on the remaining eight. There are two others being designed now in other parts of town.

    We have tons of design questions and would love an opportunity to participate in a sort of chat room or chat email system if you know of one...

    Thanks,

    Robin Lewis
    City Traffic Engineer
    City of Bend


    From: "Williams, Robert (PWD)" <rbw@co.miami-dade.fl.us>
    To: "'geno@ksu.edu'" <geno@ksu.edu>
    Subject: TRAFFIC CIRCLES & ROUNDABOUTS IN MIAMI-DADE COUNTY as of April 26
    , 1999
    Date sent: Thu, 12 Apr 2001 09:03:30 -0400

    I don't know of any source of information for the entire country, but I'm happy to contribute what I know about our county. I'm not too expert on thedifferences between the two circularly shaped roadways, but if I had toguess, I'd say we have three of each:

    TRAFFIC CIRCLES

    Curtiss Pkwy, Royal Poinciana, Westward Dr., & Palmetto Dr. in Miami Springs
    Ponce de Leon @ Sevilla & Palermo in Coral Gables
    Old Cutler Rd., LeJeune Rd., Sunset Dr., & Cocoplum Rd.

    ROUNDABOUTS

    Pinecrest & South Drives in Miami Springs
    Glendale & Beverly Drives in Miami Springs
    DeSoto & Labaron Drives in Miami Springs

    Robert B. Williams, P.E.
    Traffic Control Center Eng.
    Miami-Dade Public Works
    rbw@co.miami-dade.fl.us
    305-592-8925*247


    From: KC-Mike Wahlstedt mrwahlstedt@transystems.com
    To: "'Gene Russell '"
    Subject: roundabouts
    Date sent: Wed, 11 Apr 2001 21:50:59 -0500

    We are getting ready to start design on a couple of roundabout projects in the KC area. As you are aware, the devil is in the details in roundabout design. I have done quite a bit of research on design, but would like to not be an example of what not to do. Therefore, I am looking for an experienced designer to "look over my shoulder" on these. Are you familiar with firms that provide these services to other consultants?

    I know about Wallwork and have heard of Doctors. Are you familiar with any others who are "experts" and would provide peer review?

    Thanks for your assistance...

    Mike Wahlstedt
    TranSystems Corp.
    Kansas City


    From: Gene Russell [mailto:geno@ce.ksu.edu]
    Sent: Wednesday, April 11, 2001 9:56 PM
    To: Itetraffic@lists.io.com
    Cc: Greg Luttrell; Kalyan Sakhamuri
    Subject: itetraffic roundabouts

    We (Kansas State University) have been conducting research on roundabouts for three years for Kansas DOT, Insurance Institute and others. I conjunction with these efforts we have been developing a web site (www.ksu.edu/roundabouts) and have an interest in keeping up ( as much as possible and for as long as possible ) with the growth of roundabouts in the USA and, although the web site is now a work in progress (constructive comments are welcome), develop it into sort of a clearinghouse for anybody seeking information on roundabouts. For example, anyone of you know for sure how many roundabouts are now in operation in the USA ? Kittleson developed a really nice web site a few years ago with information on all known sites, at that time 90, but that has not been added to since then. There are other sites we have links to that cover certain areas or specific roundabouts, etc., but it is hard to get a good grip on the current state of their development and studies being conducted on them. Talking with Michael Wallwork, and others, the numbers today are no more than a guess of between 200 and 400. (anybody have a more definitive number?) Since they are being installed by many different agencies, there is no one agency in a state to get a good list in any given state. This is a request for information on all those any of you know about in your area and whatever information (jurisdiction, type, contact, picture or article if possible, etc.) you can supply us with on existing or planned roundabouts and or roundabout study results or studies being conducted. Your help would be greatly appreciated and the results available to all. We are, of course, a non profit, equal opportunity organization, doing this with our own limited resources mostly out of curiosity, but as a potential public service as well. Thanks. Gene Russell

    Eugene R.(Gene) Russell,Mark and Margaret Hulings Professor, Department of Civil Engineering, 2118 Fiedler Hall, Manhattan, KS
    66506-29
    05


    From: "Williams, Robert (PWD)" rbw@co.miami-dade.fl.us
    To: "'geno@ksu.edu'" geno@ksu.edu
    Subject: TRAFFIC CIRCLES & ROUNDABOUTS IN MIAMI-DADE COUNTY as of April 26, 1999
    Date sent: Thu, 12 Apr 2001 09:03:30 -0400

    I don't know of any source of information for the entire country, but I'm happy to contribute what I know about our county. I'm not too expert on the differences between the two circularly shaped roadways, but if I had to guess, I'd say we have three of each:

    TRAFFIC CIRCLES

    Curtiss Pkwy, Royal Poinciana, Westward Dr., & Palmetto Dr. in Miami Springs
    Ponce de Leon @ Sevilla & Palermo in Coral Gables
    Old Cutler Rd., LeJeune Rd., Sunset Dr., & Cocoplum Rd.

    ROUNDABOUTS

    Pinecrest & South Drives in Miami Springs
    Glendale & Beverly Drives in Miami Springs
    DeSoto & Labaron Drives in Miami Springs

    Robert B. Williams, P.E.
    Traffic Control Center Eng.
    Miami-Dade Public Works
    rbw@co.miami-dade.fl.us
    305-592-8925*247


    From: Phil.Jordan@roads.vic.gov.au
    Subject: Re: GREETINGS
    To: geno@ksu.edu
    Date sent: Tue, 24 Jul 2001 17:07:24 +1000

    Hi Gene,

    Great to hear from you. I trust you are keeping fit and well.

    I can happily send you a number of roundabout photos - please give me time to do this.

    Secondly - if you want an Aussie "expert" - some people consider me to be such a person!! A suggestion - why not consider running a one or two day "awareness" raising course on roundabouts. You already have some very good people in North America, including Mike Wallwork and others - pick a time which suits them and me in 2002 and we can help to promote the safe use of an excellent traffic control device (the roundabout).

    I look forward to seeing you here next Feb - I am on the Steering Committee and we have started to put together a very good program.

    Lots of hot weather at that time of the year down here. Give me a few days - will send photos 2-3 at a time.

    Cheers for now,

    Phil



    Date: Wed, 25 Jul 2001 18:58:19 -0500
    From: Gene Russell geno@ce.ksu.edu
    Reply-To: geno@ksu.edu
    To: Phil.Jordan@roads.vic.gov.au
    Cc: Sheila L Willms slw5236@ksu.edu
    Subject: Re: GREETINGS/reply

    PHIL: G'DAY We have had Michael here 5 times for courses. We love the guy. He was hired by a consultant to "sell" a roundabout to our local commission and he "failed" not that he didn't give it his "all" and do a great job -- he did -- it is just that we have some really stupid commissioners and people that think we are trying to force the Arc De Triomphe on them. You would not believe some of the comments people make in "Lettters to the Editor" sections of our newspapers. In one City a retired cop formed a group CARS "Citizens Against Roundabouts". They had billboards and Yard Signs all over town. It is both funny and sad. I will look forward to receiving pictures. Check out our website when you get a chance. Critique would be most welcome. It is a "work in progress" but we are getting it so we think it is pretty good. (http://www.ksu.edu/roundabouts) G'DAY tell me is G'DAY both a beginning and ending greeting ??? Good to hear from you.

    GENE

    P.S. Our email limit is 2M, so people can usually send only two or three at a time.



    From: "Tony Redington" treding@psd.state.vt.us
    Organization: Vermont Dept of Public Service
    To: RSLcrown@aol.com, geno@ce.ksu.edu, rsoyring@ci.traverse-city.mi.us, smallwadd@earthlink.net, Joe.Bared@fhwa.dot.gov, pgaldes@fveng.com, RRetting@iihs.org, LRODEGERDTS@kittelson.com, wallwork@mediaone.net, gluttrell@netscape.net, michael.p.ronkin@odot.state.or.us, Doctors@pbworld.com, g-jacquemart@peapc.com, treding@psd.state.vt.us, MNiederhauser@sha.state.md.us, ourston@west.net, bigrusskie@yahoo.com, dale_mckeel@yahoo.com, "Edmund Waddell" waddelle@mdot.state.mi.us
    Date sent: Fri, 29 Jun 2001 13:32:00 -0400
    Subject: Re: Upcoming issue of IIHS Status Report
    Priority: normal

    To Richard et al:

    There is no specific information to report other than the expected spring 2001 construction in Hopauge (sp?), LI of a roundabout in the downtown area, the first Mass. Highway Dept. built roundabout at Duxbury, Mass. that was to go into construction last fall, and a note last month that a design firm headed by Bill Baranowski is working on about nine roundabouts in Utah and New York State.

    My sense is that about a roundabout a day is coming on line somewhere in the US. It really is not possible at this point, unless a detailed survey is made, to put an exact number of roundabouts built and a likely rate, other than to say that we, like France, will in a year or so be adding a thousand a year. I had calls this week regarding a potential roundabout in Bellvue, Washington and the North Shore in Massachusetts--both were cases where the roundabout because one of its advantages over a traffic signal (capacity in one case and service/traffic calming in the other) is being pursued. Roundabouts--as Michael Wallwork points out--are built to solve a problem. We are working on one in Vermont, suddenly, after a lady who had just bought a car at a dealership on the corner of a high speed intersection was killed entering the intersection. The auto dealer started a petition (over 200 names) because another buyer totaled their new vehicle (minor injuries) earlier this year! It is a junction of two NHS roads, a signal is not "warranted," and the state transportation agency ignored a request of the community to scope a roundabout at this location two years ago! Looks like there will be a scoping now (road is four lane, 55 mph, with traffic lights about a half mile away).

    Even the Keene, N.H., Bypass Expansion fight (Ourston, Crown, Garder and myself have all at one time or another been a part of this one, all on behalf of the Citizens group) has a resistant NHDOT ready to build one roundabout as a sop to opponents of the bypass expansion. (Wallwork did an earlier roundabout study for the City also.) The City is just 20 miles from the first two-lane northeastern roundabout at Brattleboro.

    Tony




    On 28 Jun 2001, at 11:33, Edmund Waddell wrote:

    Hi Richard: It's good to hear from you.

    I can tell you what is happening in Michigan. Check with Tony Redington in VT and Mike Niederhauser in Maryland.

    Local jurisdictions in Michigan have built 7 rdbts so far, but 3 of them are home made designs that barely qualify, other than that they have yield signs. MDOT has arranged quite a lot of training, but we have been "proceeding with caution" and have not built one yet. We have gradually built more staff confidence and internal capability, so we now have several serious proposals and it is only a matter of time. Barry Crown's Chief Okemos Roundabout in Ingham County still has a perfect safety record after a year of operation (the previous signal had 5 crashes peryear). Leif Ourston's MSU rdbt has been operating almost as long with 35,000 ADT and 6-7,000 peds, and has had only one side swipe collision at last report. MDOT staff can observe those rdbts at their leisure.

    On May 30, 2001, the Village of Dimondale, Michigan opened North America's first Mini-roundabout, at a 3-leg intersection in a 25 mph zone. It comes complete with 21-meter ICD, 5-meter entries,~1500 DHV, traversable 4-meter dome, circular pavement arrows, improvedlighting, and British-style bollards on the splitter islands - very chic. The TOTAL project cost was $35,000 (I know that's an awful lot of money, but it also included resurfacing). They are still doing some post-project evaluation and engineering, but we definitely have a winner here, and the village is already contemplating another one.

    We have eleven high-capacity (3,500 - 6,500 DHV) roundabouts planned for the Northwestern project, which will probably be built in 2006 or so, plus an unknown number of local proposals and plans - I estimate perhaps as many as thirty - some of which will probably be built sooner. Acceptance continues to improve rapidly, so I anticipate we will continue to see an exponential increase in their acceptance/use in Michigan. Folks can now observe the advantages and opposition is quickly fading.

    The biggest problem I see now is that many of the folks planning, designing, engineering, building, and painting them have never seen a roundabout in their lives, or at best have never before performed their professional role on a rdbt project. Consequently they are getting things wrong that could easily be avoided with some training and direct supervision. In your article, you should emphasize that there is much more to a good rdbt design than it seems at first, and that folks should get experienced advice and heed it.

    Ed

    >>> Richard Retting RRetting@iihs.org 06/25/01 11:39AM >>>
    In the Institute's next issue of Status Report, we'd like to briefly report on the extent of roundabout construction across the U.S., giving credit to those states that have been very active in promoting roundabouts.

    We'd appreciate your insights on the following questions:

    Approximately how many modern roundabouts ahave been built so far in the US, and approximately how many are in the planning stages?

    What specific states have been most active in building modern roundabouts? How many roundabouts would you estimate have been built in each of these states?

    Are there states with a lot of active interest in building roundabouts, although few have been built ("up-and-coming" roundabout states?)

    Thanks for your help.

    Richard Retting
    Senior Transportation Engineer
    Insurance Institute for Highway Safety
    1005 N. Glebe Road
    Arlington, VA 22201
    703 247-1582 (voice)
    703 247-1587 (fax)

    Tony Redington
    Vt. Dept. of Public Service
    112 State St.
    Montpelier, Vermont 05620
    Tel. 802-828-4039
    FX 802-828-2342


    Per Garder
    To: "'Michael wallwork'" Copies to:geno@ksu.edu
    Subject: RE: FW: Roundabout Research
    Date sent: Mon, 6 Aug 2001 09:02:15 -0400

    Michael,

    I did not know that you were 'part' of this discussion. I just sent Gene some more comments and will paste them here. Maybe you yourself can comment on why Australian injury crash rates are so much higher than Scandinavian ones. Or maybe Leif has misquoted Australian data.

    -Per




    From: Gene Russell [mailto:geno@ce.ksu.edu]
    Sent: Monday, August 06, 2001 12:35 PM
    To: Per Garder
    Subject: RE: FW: Roundabout Research

    Per: Sorry if it bothered you that i forwarded your comments to a couple friends. I enjoy discussing things with Michael. I don't make anything "public,"like on our website, without permission, although we all have to realize that the "web" by nature is pretty public. I would like to set up a discussion section on our web site as suggested some time ago by Michael, and probably will in a few weeks. You bring up some excellent points. However i am, and will always remain, against using roundabouts strictly for speed control on arterials. As a bye product, fine, but not for speed control being the only reason. To get extreme, we could reduce deaths on our highways from around 42, 500 deaths/year to probably less than 5000 if we had a strictly enforced , national speed limit of 15 mph. You think you could sell that to the USA public? My point is that our highways are primarily for mobility and that is as it should be. I am not against 15 mph for neighborhood roundabouts , and 22 to 25 (max) for collector and arterial roads, (as Michael says, it depends upon the environment ) but 15 mph everywhere just will not sell in most of the US. You want answers to Australia's situation, try Phil Jordan at vic roads. I will send you his email if I can find it. . If you could get any pictures from Sweden for our web site I would appreciate it. Do you have any contacts there ? best regards, gene


    From: Per Garder
    To: "'geno@ksu.edu'"
    Subject: RE: FW: Roundabout Research
    Date sent: Mon, 6 Aug 2001 13:37:04 -0400

    Gene,

    I was not offended that you shared my thoughts with Michael. Just a bit surprised. But, the right-to-know-act in Maine means that anything I write is public, I think, since I work for a State university.

    In the enclosed e-mail attachment is a document which hopefully will not be lost in the transfer. It is a virus-free report in English with several photos from Sweden, and empirical data showing that roundabouts are safer than diamond interchanges along two-lane highways with high on and off volumes at that spot.

    And, I like driving fast myself. I seldom go below 75 mph on the Interstate here in Maine and like cruising at 100 - 110 mph like most Europeans, where that is legal, so I am not someone who do not understand that people like to drive fast. Only in the US do I find that people accept low speed limits (and keep them) and high-speed design. I know that I should be driving slower myself, and that is why I appreciate designs that force me and others to do it. (I am not completely irresponsible, in 30 years of driving I have been involved in one accident, when I was hit from behind, and I have not had a speeding ticket or any other type of ticket in over 20 years.)

    I believe that arterials should be built for high-speed movement, and go around towns. But if an arterial goes through someone's shopping mall, then those people's needs should be accommodated too. Until a bypass is built that may mean speeds of less than 20 mph. In Sweden, that will be the standard speed limit soon wherever pedestrians are crossing. For rural roundabouts, 25 mph is fine. But, the difference in delay between 15 and 25 mph is only a few seconds. And like Michael wrote, capacity increases with lower speeds, at least down to 20 mph. Signalizing an intersection gives more delay (unless the minor flow is very low) than a roundabout with a 15 mph speed.

    You are right that a 15 mph speed limit everywhere would make it even safer. But the delay, like you tell me, would be unacceptable to us all. However, I do not believe that 'we' will find 15 mph urban roundabouts unacceptable in the long run. (And, since a high percentage of crashes occur at junctions, that is where we should make things safer in particular.) Though you have an example of one having been reconstructed to higher speed at least partially for that reason. If it was in a rural setting, I understand. If it was in a busy village environment, I think DOT should not have given in to the pressure.

    -Per



    From: Gene Russell [mailto:geno@ce.ksu.edu]
    Sent: Friday, August 03, 2001 4:15 PM
    To: Per Garder
    Cc: Michael Wallwork; Greg Luttrell; Phil.Demosthenes@dot.state.co.us;Joe.barad@fhwa.dot.gov; WALSHB@WSDOT.WA.GOV
    Subject: Re: FW: Roundabout Research

    Per Garder: I only have time for a few comments. First, thank you very much for your comments and critique of our web site. I will post your comments if you wish. i want to set up something so people can post comments on anything on the site directly, but we are not there yet. I tend to personally not agree with your comments. First, however, let me say i am philosophically against unreasonably low speed limits anywhere and i consider 15 mph generally too low anywhere. however, i have no problem with a 15 mph design for a roundabout in residential neighborhoods on residential streets. for arterials and most collectors i believe it is too low and the design should be in the 20 to 25mph (max) range.There was one designed on an arterial here for 15mph (or lower) and it was a Public relations disaster. The city had to close it down and redesign the entry radii to a more reasonable 22 to 23 mph - and then the outcry settled down. And although it still is not perfect, it works. The problem (and this is the number one problem down the freeway there is the potential a driver will come across the median and hit us head on. Likely? No, thank goodness, but the potential exists. the old roundabouts I refer to have higher speeds. Higher speeds mean more serious crashes. that is simply a law of Physics. To not believe that, is to not believe in the laws of Physics. Again, thank you for the comments and I look forward to more of your ideas.

    gene russell




    From: David Church [mailto:Church@ksdot.org]
    Sent: Thursday, August 02, 2001 3:16 PM
    To: garder@maine.edu
    Cc: geno@ksu.edu
    Subject: Roundabout Research

    Dr. Garder,

    It was very nice visiting with you today regarding roundabouts and traffic calming in Kansas. It was nice to hear what your involvement has been with roundabouts, and pedestrian safety in Maine, as well as in other parts of the world. As I stated, if you would like to find out more about what research is being done in Kansas, I would contact Dr. Gene Russell at Kansas State University in Manhattan. Below is Dr. Russell's e-mail address:

    geno@ksu.edu

    Also, for your information is a copy of the KSU Roundabout web-page. It may be of some interest to you as well.

    http://www.ksu.edu/roundabouts/

    If you have any other questions about what Kansas is doing with regard to roundabouts, please don't hesitate to call me at (785) 296-3618.

    David Church
    Senior Traffic Engineer
    KDOT, Bureau of Traffic Engineering




    From: Michael wallwork [mailto:mwallwork@yahoo.com]
    Sent: Saturday, August 04, 2001 1:02 PM
    To: geno@ksu.edu; Per Garder
    Cc: Michael Wallwork; Greg Luttrell; Phil.Demosthenes@dot.state.co.us; Joe.barad@fhwa.dot.gov; WALSHB@WSDOT.WA.GOV
    Subject: Re: FW: Roundabout Research

    I am not sure if my previous set of comments actually went. So I am sending them again.
    I have always designed rbts to suit the environment, 15 mph in residential street, up to 23 mph for arterial roads. In Australia they alsyws do the same.
    To do otherwise can lead to disenchantment or too high a speed for the envoironment. This is not the first one that was designed too small. Design speeds over 25 mph will lead to much higher crash rates and reduced capacity as speeds increase and drivers need larger gaps to enter, less capacity, higher speeds mean less time to avoid problems.


    From: MacDonald, Doug
    Sent: Monday, July 30, 2001 4:42 PM
    To: WSDOT ER All Users; WSDOT NC All Users; WSDOT NW All Users; WSDOT OR All; WSDOT OSC All Staff; WSDOT SC All Users; WSDOT SW All Users; WSDOT WSF All Staff
    Subject: Familiar Face Returns to WSDOT

    I am very pleased to announce the appointment and return of John Conrad to the Washington State Department of Transportation. John has accepted my offer to serve in the newly created position of Assistant Secretary, Engineering and Regional Operations.

    John returns to the Department after working with the private firm of Parsons Brinckerhoff Quade & Douglas Inc., where he worked in program management for the British Highways Agency on the motorway and trunk road system in the United Kingdom.

    Before his working as a private consultant, John served at WSDOT for 23 years in multi-modal planning, local programs, traffic operations, and maintenance. He has been tireless in his work to provide a safe environment for employees in construction work zones. He last served as Assistant Secretary of Field Operations Support. We are pleased to have John rejoin the management team and demonstrate his ongoing commitment to the success of the agency.

    John received a bachelor's degree in civil engineering from the University of Nebraska, and a master's degree in regional and community planning from Kansas State University. John is a licensed professional engineer.

    John will begin his new duties on Friday, August 3. Please join me in welcoming him home.

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