The NZ Transport Agency has expressed concern about the lack of improvement in fatal and serious cyclist injuries on low-volume rural roads since the Safer Journeys strategy was launched. This investigation aimed to determine how to cost-effectively improve the safety of people who cycle on lowvolume rural roads in New Zealand. A low-volume rural road was classified here as a non-state highway road in a rural area with a daily traffic volume of 3,000 vehicles/day or less. In the NZ Transport Agency’s One Network Road Classification, this definition equates to roads at the ‘Primary collector’ level or below. A total of 354 cyclist-motorist crashes were recorded on low-volume rural roads in New Zealand between 2004 and 2013, resulting in 18 fatalities, 96 severe injuries and 236 minor injuries. While cycle-only crashes are also important in a rural context, where road maintenance is typically lower, the focus of this study was to examine cyclist-motorist interactions as that is where existing data and literature suggest there is a large social cost. Illustrating this fact, the total social cost of aforementioned crashes was estimated to be over NZ$161million (or $16 million per annum). Overtaking and rear-end crashes (40% combined) were the main crash types associated with these low-volume rural roads crashes. Internationally, there has been a range of solutions put in place to enhance the safety of cyclists on rural roads. The Dutch 2-1 solution has been argued to be the most successful, which involves centreline removal, 1.5m to 2m wide cycle edge strips on each side of the road, and a speed limit of 60km/h. Threshold treatments include posted speed limits, transverse lines and physical obstacles. Following the literature review and crash analysis, two treatments were identified for trial: • advisory signs on passing distance • 2-1 layout (adapted to the New Zealand context) + rural sharrows (shared space arrows) on curves + 60km/h speed limit. Unique baseline data was also collected. The 2-1 component appeared to be intuitive to most drivers and riders, but was discontinued after a 24-hour observation period based on safety reasons and public complaints. The sharrows in this section were left on the ground so that the two treatment conditions became the signage treatment and the sharrows treatment. The performance of the road treatments was measured in real-world settings to ensure ecological validity. Driver behaviours were observed naturalistically, using the following key performance measures: • approach speed (of passing vehicle) • passing distance (distance from cyclist to vehicle) • bicycle speed. Metrocounters also measured overall speed data of all motorists at two locations. Cyclist and driver data was obtained using an integrated suite of instrumentation on four bicycles. The instrumentation included: • an ultrasonic device to capture the separation distance between cyclists and vehicles • a radar device to capture the speed of approaching vehicles • a rear-facing camera to capture vehicles as they approached • a GPS unit to determine cyclist position on the route. The route for the on-road trial was located in the Waipa District and was selected as it is a relatively low-volume rural road (AADT <1000) that is popular with local cyclists for training and recreational rides. Eleven cycling participants were recruited from cycling clubs and local contacts in the wider area. Drivers included all vehicles that travelled on the route during the trial times. No significant differences were found between the signage or the sharrow treatments and baseline on any of the three key performance measures taken by the instrumented bicycle: approach speed, passing distance or bicycle speed. The lack of significant differences between baseline and treatments did, however, allow the data to be combined to provide unique baseline data for the three dependent variables for these kinds of roads in New Zealand (see the table below). It also revealed that about four in every five drivers provide cyclists with the recommended (ie 1.5m or greater) passing distance. The Metrocount data indicated that there was no change in average free-flowing vehicle speed as a result of the sharrows, but there was a 2km/h speed reduction in the signage treatment area. There was also a positive daytime finding for the 2-1 design, where the design was able to reduce average motorist speeds from about 90km/h to about 62km/h. However, night speeds for motorists travelling through the 2-1 design were still higher than desirable. Based on the findings of this project, Opus Research recommends that the following be considered: 1 Further 2- 1 trials in the New Zealand context: Future trials are recommended to further inform the 2-1 design applicability in the New Zealand context. These design trials need to be conducted in conjunction with robust threshold and midblock treatments, including more active speed management measures (particularly at night). Complementary behaviour-based signage must be used to ensure all road users in the treatment location are exposed to explicit information demonstrating correct user behaviour. Similar, low-volume rural road designs with limited space (such as roads with no centre lines) could also be used to draw comparisons with user behaviour on existing New Zealand roads. 2 Community consultation, communications and engagement strategy: While the 2-1 design may be intuitive to most motorists and cyclists, any future trials of the 2-1 design (or other new or innovative designs) must be accompanied by a robust communications and engagement strategy, including education about new road layouts use and potential benefits. This communications strategy should be the joint responsibility of the appropriate road controlling authorities and the research and evaluation team, and should obtain a high level of community buy-in before trials proceed to implementation. 3 Advisory distance signs: Use advisory distance signage as part of a suite of measures to improve the safety of cyclists on rural roads. These signs have been shown to lead to a significant reduction in vehicle speed (a speed reduction that has the potential to benefit the safety of all road users). 4 Standardised advisory signs: The NZ Transport Agency consider the development of a standardised advisory sign to encourage desirable overtaking behaviour when passing cyclists, and guidelines for its use to ensure consistency across the national network. The sign used in this project is similar to that being trialled for high-risk motorcycling routes (so is consistent), and has been shown to lead to speed reductions, so could serve as a starting point for this development. 5 Baseline cyclist- driver data: A robust baseline of how drivers and riders interact in different settings and road hierarchies would better inform and monitor safety intervention outcomes. (Author/publisher)
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