Flawed analysis behind BusConnects proposals to divert cyclists near Marino

COMMENT ANALYSIS The National Transport Authority are proposing to off the main road Marino and Fairview as part of the Clongriffin BusConnects Core Bus Corridor. The Malahide Road narrows as it approach and there isn’t the space to accommodate the desired road layout of the National Transport Authority (NTA).

The decision to divert cyclistswas based on analysis undertaken by engineers working for the NTA. It found that when you consider all of the pros and cons that diverting cyclists was the most preferred option. However, there are two flaws with this.

The diversion uses low-traffic and low-speed residential roads in Marino. Though local residents are trying to stop some motorists using these roads as a rat run.

This is a good alternate route for cyclist leaving the city. In fact many cyclists already use it to avoid the main road. However, for cyclists heading into the city it is a poor option as it requires them to wait at two extra sets of lights.

The cyclist diversion is the dotted line above

The NTA have published the full multi-criteria analysis behind the decision to divert cyclists. This analysis examined four options to determine what was the best option based on 5 criteria: economy; transport integration; accessibility and social inclusion; safety and environment.

The four options were:

  • Scheme 1: southbound bus lane, and cycle tracks in both directions
  • Scheme 2: divert all cyclists through Marino. Bus lanes in both directions
  • Scheme 3: divert southbound cyclists through Marino, provide an northbound cycle track and an southbound bus lane
  • Scheme 4: divert northbound cyclists through Marino and southbound motorists via Copeland Avenue and Howth Road. Bus lanes in both directions

After weighing up all of the pros and cons the engineers found that Scheme 2 was the most preferred option. However, there are two flaws in the analysis.

Flaw One: Scheme 3 should have won

In the end there was little scoring different between Scheme 2 and Scheme 3. Scheme 2, which diverts all cyclists, only beat out Scheme 3 on the environment criteria. On initial inspection this seems odd. Scheme 2 has a total road width of 15.6m compared to 14.35m for Scheme 3. How did the wider option have less impact on the environment? The answer: a mistake was made.

Scheme 2 includes a bus lane in both directions and no cycle tracks

Scheme 3 includes a northbound cycle track and a southbound bus lane

The environment criteria is based on seven sub-criteria. Scheme 3 performed better than Scheme 2 on the Flora and Fauna criteria. The narrower option had less impact on plants and trees in front gardens. However, Scheme 2 performed better than Scheme 3 on the Architectural and Cultural Heritage criteria. It found that Scheme 3 would have an impact on the “boundaries of two protected structures”, numbers 62 and 64 Malahide Road and Scheme 2 would not. It’s strange that the wider option doesn’t impact on the protected structures but the narrower option does.

Scheme 3 is the option in the public consultation. On map 20 you can see that the NTA proposes to move the boundaries of the protected structures. Scheme 2 and Scheme 3 should have the same score for the Architectural and Cultural Heritage criteria.

A section of map 20 from the public consultation that show’s boundaries of 62 & 64 Malahide Road affected

Taking all of this into account Scheme 3 should have a better environment score than Scheme 2 and it should have been selected as the overall most preferred option.

Flaw Two: Comparing apples and oranges

The second flaw is that the analysis doesn’t always compare like with like. Scheme 1 provides cycle tracks in both directions. From a purely cyclist point of view this is the best option. The NTA analysed this option, which is 17.2m wide.

Scheme one includes a cycle track in both directions. There is no northbound bus lane for the first 180 metres.

At 17.2m it is much wider than Scheme 2 (15.6m) and Scheme 3 (14.35m). As the widest option it has the largest cost and the greatest impact on the environment. In Scheme 2 and Scheme 3 the proposed footpath was the minimum allowed width of 1.8m. In this option they are 2.2m and 2.5m. This increases the width of the cross-section by more than 1.1m, which adds to the cost and environmental impacts.

It’s odd that they’re proposing a 1.8m footpath beside bus lanes but propose wider footpaths beside a cycle track. The NTA is not comparing like options with like options, which is the second flaw.

Northbound bus lane

Scheme 1 and Scheme 3 do not include a northbound bus lane, which is the current situation. Buses and general traffic would share for the first 180m of the Malahide Road. Based on the NTA’s report and traffic queue length data this could cause delays for buses, but is unlikely. The benefits of an outbound bus lane could be achieved using other bus priority measures such as bus-only traffic lights.

Other options

When the NTA repeat this analysis they should add a new option that includes southbound cycle track and diverts northbound cyclists. The currently proposed diversion is acceptable for northbound cyclists but a poor option for southbound cyclists. The NTA should also consider options with wider footpaths and cycle tracks than the current options, especially since options like Scheme 3 are 1.1m narrower than the currently proposed option.

Determining the best option for this short section of Malahide Road will not be easy. But it is vital that the analysis that underpins this decision is solid. Currently it’s not and it should be repeated.

Kevin Baker is a member of the Dublin Cycling Campaign. All of the above information is included in the Dublin Cycling Campaign’s submission on the Clongriffin CBC.

I'm a volunteer with the Dublin Cycling Campaign's infrastructure group. My primary focus within the campaign is to ensure that BusConnects delivers for cyclists and the future cyclists of Dublin.

5 Comments

  1. Due to human error when fixing an unrelated hosting issue a few articles were deleted and manually restored. Unfortunately, I was unable to restore comments in the last four articles — I am sorry for this error and the loss of reader’s comments.

  2. My comment was to thank Kevin for writing the article. Thanks Kevin! And to also endorse what was said by ….can’t remember who it was (Sam?)… about the roads at the southern end of the route.

  3. As I was saying :

    I live in one of the streets, Carleton Road, where they want to move all cyclist to. This road is not suitable for heavy cyclist traffic. There are cars parked illegally on both sides of the road, narrowing it so only a single car can pass. I have witnessed a number of altercations between car drivers and cyclist as the latter are “in their way”.

    The solution for me is to send all southbound motorised traffic through Copeland Avenue and then Howth Road where they can join Clontarf Road. Copeland Avenue does have speed bumps so it may annoy the drivers so much that they would choose a more suitable road, like Collins Avenue a bit more North. This will leave room on that part of Malahide Road for cyclists and busses in both directions and northbound for cars.

    When will planners learn that cyclist will not take a diversion when it does not make sense? They will go on the footpaths if needed to avoid the long way around. This will likely cause aggravation with pedestrians and may also cause some dangerous situations. Cars have no choice so will have to take the diversions so it would be much easier to manage.

  4. @Sam – have you made a submission to Bus Connects with your thoughts on this?

    Regarding Sam’s point about diverting cars to the Howth Road – this is the sort of thing that planners need to start doing. We need to prioritize our travel modes with walking, cycling, and public transport, in that order, as per all the accepted international thinking on this. If road space needs to be removed for one mode of travel, then private cars need to be shoved to the bottom of the heap. Not only do we need to prioritize, sustainable transport like walking/ cycling / public transport; in some areas we also need to actively disincentivize the use of private cars. We need to make it difficult and annoying and frustrating for people in cars so that they choose not to use them.

    I’ll bet that there’s little chance of this actually happening at this location; but it certainly won’t happen (& it’ll be people on bikes that are diverted) unless we make enough of a stink about it.

  5. AnnoymousEngineer January 7, 2019 at 11:56 am

    I’m not saying it’s perfect but a couple of points on the flawed analysis.

    Flaw 1: Scheme 3 has a cross section of 14.35m for the narrowest (180m) section of Malahide Road only, this is to the south of Crescent Place. To the north of Crescent Place a northbound bus lane is introduced which widens the cross section to 17.35m. This is why it requires more land take and impacts more on the protected structures

    Flaw 2: At the sections where land take from gardens is required, the minimum allowable footpath width of 1.8m is used, in order to mimimise the amount of land take required. On the sections where land take is not required, the full available road cross section is used with any remaining space allocated to providing wider footpaths. This is why schemes with narrower overall cross sections occasionally have wider footpaths. I’m not sure where the cross sections shown above are taken but they may be in different locations along the road with differing available road widths

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