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    Pictures of Newzealand Roundabouts

    DOUGLAS STREET Roundabout


    PERTH STREET Roundabout


    OTIPUA Roundabout


    CHURCH STREET Roundabout


    E-MAIL NEWS FROM PERSON WHO SENT THE ABOVE PICTURES

    From: ANTONI FACEY To: geno@ksu.edu
    Subject: Roundabouts
    Date sent: Mon, 16 Sep 2002


    Dear Gene
    I understand from Ian Appleton that you are looking for pictures of roundabouts. I have designed a few that I am fairly happy with (obviously I would change things with the benefit of hindsight but they still work well). I have checked the crash records and all have met the criteria of reducing the crash rate from the previous control and the crashes are of lower severity than previously. One intersection had 3 cycle crashes but none after the roundabout was installed; not the usually expected result. On this measure, you can say they are good roundabouts but there is still some room for improvement. I could probably get copies of the aerial photographs from the local authority if you like. All of them are non standard with difficult horizontal approach geometry. There are a few things that I have found in my city that I have not sen anywhere else. I have spoken to others and they have never heard of it either. We have the ring around our roundabout circulating islands to allow for tracking of heavy vehicles. These were constructed using the same interlocking concrete block paving as the footpaths (not my choice). Pedestrians now regularly walk around the inner circulating ring where they should not be. You should be careful that designers do not carried away with landscaping features such as that to the detriment of logical arguements.
    As a safety auditor, I have seen many roundabouts around NZ and I am quite satisfied that the roundabouts I see these days are much better than those in the past. Almost invariably, they have good geometry or only minor faults, but the finishing touches such as landscaping and roadmarking often let the result down. I post construction audited one last week that had been planned and designed as a 2 lane roundabout then a decision was taken to drop the roundabout to a single circulating lane without physically altering the approaches. Neither of us in the team could accept that it should work safely but when observing behaviour, there appeared to be no problems. The drivers sorted themselves out well. It was a larger roundabout with only 3 approaches so that may have had something to do with it.
    You should be aware that in Christchurch City which was the first city in NZ to really begin the widespread use of roundabouts about 30 years ago, many of the roundabouts are being replaced with traffic signals. There are not many new ones being built there. This is due to the capacity issues of increasing traffic volumes.
    One reason we have had so many roundabouts in NZ is our funding regime. It is much easier to financially justify a roundabout than traffic signals since you do not have the same impact on main road traffic flow as with traffic signals and off peak they are more efficient. Hence, we have had some roundabouts put in where they should not have gone for technical reasons. When the roundabout is the do minimum, it becomes easier to justify traffic signals.
    A common fallacy is that you should not have any plants, etc on the circulating island. I have found through my crash investigation studies and safety audits that this is not the case. I have even audited a site where we erected a large concrete architectural structure in the circulating island. The approaches took care of all of the deflection through the horizontal alignment and it was not possible for a vehicle at the low design speeds to strike the structure. There was enough visibility left for vehicles at limit lines to determine the intentions of the circulating vehicles safely.
    I am happy to discuss these issues further if you would like but I do not have many photos. To get photos, I would need to be in that part of the country and that depends on where my next client takes me.
    Regards
    Antoni Facey
    BE (Civil), Registered Engineer
    39 Quarry Road
    Timaru
    Telephone (03) 684 6665
    Mobile (021) 148 7851


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    Kansas State University
    September 9, 2009