One of the big factors that make a bike path rideable is the path gradient. If it is too steep, and we will find ourselves pushing uphill. Bike paths, poorly designed, can be too steep to ride. A case study of Whitlam active travel network.
Description of active travel routes
Description of active travel routes through/beside Whitlam. Here we discuss Local and Main Community Routes.
Main Community Routes (MCRs)
These are the “arterials” for active transportation and connect PCRs to group and employment centres. Connected destinations also include hospitals, industrial areas and the airport precinct as well as major active travel venues such as Stromlo Forest Park.
There are a number of different types of Main Community Routes that have different purposes such as connecting town centres by alternative routes, links to other MCRs and PCRs to form a connected network and inner-urban loops in town and group centres. The latter allow higher amenity movement around these destinations with PCRs and MCRs generally terminating at the loops.Planning for Active Travel in the ACT: Active Travel Infrastructure Interim Planning Guideline (ACT Government, January 2019), page 22
Main Community Routes
Important Main Community Routes are on either side of Whitlam running north-south, but the utility of the routes will be reduced by the very high gradients traversing the deep river valley. Both Coppins Crossing to the east, and the other route to the west, are low-level crossings. Unless measures are taken, the gradients on these paths could exceed Austroads guidelines.
Local Community Routes
The Local Community Routes along the streets are steep in places but should be rideable. The utility is then dependent on the treatments for the frequent crossing of the adjacent side roads. These side roads were the subject of an email Whitlam Stage 2 estate design falls short on active travel (2020) to EPSDD. The email’s message is now strengthened, as most rideable paths across Whitlam are along a street. The Local Community Route along the ridge, starting at the roundabout (figure 6) is too steep to be rideable (Austroads standards). The path is therefore poorly labelled a Local Community Routes but would be better referred to as a Recreational Route, for which gradients are much less important. There are no direct east-west Main Community Road through Whitlam so that the Local Community Routes adjacent to the streets (particularly Sculthorpe Avenue) increase in importance. The schools and shops in Molonglo 3 are along an east-west axis. This is likely to add to the popularity of these Local Community Routes.
Commuting to work from Whitlam
Whitlam is the extreme end of the Molonglo Valley Stage 3 development, a dead end which is unfortunate. With time, the Main Community Route to the west may be connected to Whitlam as part of Whitlam Stage 4 (past the Kama Reserve corridor). Commuting to Woden and Tuggeranong awaits the completion of the John Gorton Drive Bridge over the Molonglo River. Commuting to Belconnen is hampered by the lack of off-road cycle paths directly north along Coulter Drive. A direct off-road route to commute to the city is missing until Main Community Routes through Molonglo 3 East are completed. Commuting by bicycle from Whitlam is therefore unlikely to be popular for some years.
The Molonglo River Reserve is a narrow river corridor with steep drops down to the river. See figure 1.
Not surprisingly, the housing estates are being built either side of the Molonglo River on the “flatter” sections. The creeks flowing into the river have strongly eroded the valley. Figure 2 and 3 show the gradients of a natural landscape from a Whitlam survey (2014) before the ACT Suburban Land Agency had flattened it out. Gradients of 5-10% are most common, but around Deep Creek the gradients exceed 25%.
The Austroads standards for bike path design recommend that a bike path never exceed 12% as children cannot ride down this gradient safely. The same standard recommends that riders struggle with prolong section of riding uphill of gradients of just 5%.
For reference, the bike path up Aranda hill from the Glenloch Interchange has for a short 100 m section with an 8% gradient. Generally, the gradient on Aranda hill is much more moderate, nevertheless, most people regard the 70 m rise to the saddle as challenging.
Whitlam Estate Plan
The Whitlam Residential Estate Concept Master Plan 2018 (CONCEPTMASTER-201834628-01 20180706) shows that the estate has been flattened through cut and fill. This makes the suburb flatter, but it is not all that flat. Most of Whitlam has a significant slope. Because of this, Molonglo Valley Stage 3 district playing fields will be built north of William Hovell Drive on the horse paddocks.
Here are three views of Whitlam.
- Figure 4: Overview of the Whitlam Residential Estate
- Figure 5: Deep Creek Pond and drop into the Molonglo Valley, Whitlam Residential Estate
- Figure 6: Local Community Route from Deep Creek to the centre of the suburb
Note here that the yellow areas where the houses are to be built are generally flatter than the green surrounds (figure 4). The edge of the estate drops off into the river valley (figure 5). The ridges that could not be removed are to become parks (figure 6). These parks are often the steepest sections of the estate. For that reason, one would not build Local Community Routes on the ridge, but the Whitlam Estate Plan shows that this is planned.
The ridge bike path
Some paths in Whitlam are very steep. This section is a case study of the bike path long the ridge, climbing from the roundabout on Sculthorpe Avenue. At the time this article was first written in 2020, this road did not have a name and was called “Road 01” on the Whitlam Estate Development Plan.
Unfortunately, it is not possible to calculate the gradient of these paths from the Whitlam Estate Development Plan. No doubt the ACT Suburban Land Agency has this data, but it was not part of the Development Application for Stage 2 (Whitlam Stage 2 Development Application 201936061, 10 September 2019).
It is worth noting that gradient analysis of bike paths was not mandated in the development application process. Without such analysis at an early stage, there is no way to know if the proposed alignments are suitable for cycling. This must be seen as a major oversight of the planning.
Figure 9 shows how the Whitlam Active Travel Network. Local Community Routes follow the streets for the most part, in some case adjacent to Local On-road Routes. The equestrian routes (YELLOW) have, at the best, recreational value for cycling. The PINK line winding its way through Whitlam is also a recreational route. The Main Community Routes are light BLUE, and run north-south on both sides of Whitlam. The Main Community Route on the east side runs along John Gorton Drive.