The Coppins Crossing is a river level crossing on the Molonglo River built to rural road standards and only suitable for low volumes of traffic. As a north-south corridor and part of the Molonglo development, the traffic volumes along Coppins Crossing Road are high.
Coppins Crossing Road is an example of a popular Canberra road without bike lanes. On-road cycle lanes in the ACT are also discussed here.
The most recent update on the John Gorton Drive Bridge is found here from 12 February 2021.
Factors in road design
Road design has evolved to put great emphasis on road safety. Coppins Crossing lacks much and the following considerations are discussed here:
- Road reserve and cutting
- Exposure length
- Marked shoulder
- Cycle lane
- Country road grade
- Road maintenance
- Gradient
Road reserve and cutting
“Road reserve – Land comprising the road and verge. And also referred to as the road or street corridor in this Standard.”
Active Travel Facilities Design – Municipal Infrastructure Standards 05 (ACT Government, April 2019)
The Coppins Crossing Road is very narrow and steep either side of the river-level crossing. The road is cut through the side of the valley to reduce the gradient. The cutting is just wide enough for two way traffic. The road reserve provides no verge for the cyclist to leave the road, such as in an emergency.
Marked shoulder
“Marked shoulder – Refers to the sealed edge of roads outside of the travelled carriageway defined by an edge line (the shoulder) where cyclists are legally allowed to travel. This facility is almost invariably associated with unkerbed roads and is often used on rural roads.”
Active Travel Facilities Design – Municipal Infrastructure Standards 05 (ACT Government, April 2019)
Much of the on-road cycling in the ACT is done on the marked shoulder of the road as it provides some segregation from the road traffic. Coppings Crossing Road is lacking even a marked shoulder on much of its length.
Bicycle lane
“Bicycle lane – A special-purpose on-road traffic lane for the exclusive use of cyclists marked in accordance with Australian Road Rule 153 and as described in AS1742.9 and AGRD03 Section 4.6.7. Bicycle lanes may be of varying widths depending on the road speed environment and their use is defined by the Australian Road Rules for cyclists and other road users.”
Active Travel Facilities Design – Municipal Infrastructure Standards 05 (ACT Government, April 2019)
The Coppins Crossing Road does not have a bicycle lane and none is planned.
Exposure length
“Exposure length – The length of a bicycle lane, typically at a slip lane, in which the cyclist can be regarded as having a high risk of conflict with vehicular traffic.”
Active Travel Facilities Design – Municipal Infrastructure Standards 05 (ACT Government, April 2019)
Exposure length is a useful concept as Coppings Crossing Road is steep, narrow, without marked shoulder and bicycle lane, and the cyclist can be regarded as very vulnerable. Steep and narrow is a bad combination as the cyclist is then unsteady and slow. At low speeds, the time spent in the exposure length is greater, thereby increasing the risk. On steeper grades, cars have higher speeds and less control. The cutting means for the cyclist there is no escape. Particularly the south side of Coppings Crossing is very dangerous.
Rural road standard
Some roads are very old and were built in a way that would not comply with modern road standards. In the ACT rural roads are often sealed old roads that predate Canberra’s urbanisation. Many of these roads have been upgraded but some still survive, including Coppins Crossing Road. Roads built to rural road standards are only suitable for low volumes of traffic. Now, in the middle of the Molonglo development, the traffic volumes along Coppins Crossing Road are high.
Road maintenance
As a result of the John Gorton Drive 3C Extension, road maintenance of the Coppings Crossing Road seems to have been discontinued. Road edges are breaking away, the road is uneven and potholes are forming. The narrow and windy road is a hazard to both motorists and cyclists that share the road.
Gradient
The Austroads AGRD06A standard includes recommendations for uphill gradients for cyclists. The “desirable uphill gradients for ease of cycling” (AGRD06A, page 34) depend on the duration of the climb. For a 5% gradient, the “desirable” length of the gradient is no more than 80m.
The conditions found for the cyclist at the Coppins Crossing considerably exceed. There is a section close to 10% for a length of approximately 180m and a gradient of 9% on the north side for a length of 100m. Gradients above 5% are common. Coppins Crossing is not compliant with the Austroads AGRD06A standard.
Conclusion
The ACT Government must regard the Coppins Crossing road as unsafe by its own road standards. Even adults and experienced cyclists are ill-advised to ride there.
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