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Daily Archives: May 1, 2024

Another roadblock for active transport?

The Metro Manila Development Authority (MMDA) recently released what they claim to be their counts of bicycle traffic along major roads in Metro Manila from 2020 to 2023.

These are supposed to be official data as it is issued by the government agency in-charge of traffic management for Metro Manila roads (aside from its other functions and roles). What are not stated, and are actually very important details, are the locations of the counts and when the counts were conducted.  The Traffic Engineering Center (TEC) that was under the DPWH and currently with the MMDA used to publish traffic volume maps for major roads in Metro Manila. So along EDSA, for example, the volume per section are shown on the map. The same for other major roads like Commonwealth, Quezon Avenue and SLEX. The thicker lines mean higher volumes along those sections, and vice versa. However, they did not consciously count bicycles (only motor vehicles) and perhaps MMDA only started counting during the pandemic (i.e., 2020). So there is no one value to represent a road. And counts vary over time of day, day of the week and even throughout the year (i.e., monthly variations).

There were many reactions to the MMDA’s posting of the data and most were critical and even derided the agency for what to them appeared to be inaccurate data. The problem is that it seems there are no other counts that can validate and perhaps refute the MMDA data. Previous bike counts were not conducted according to how the MMDA and DPWH count vehicles. That is, counts are typically done over a 14 or 16-hour period and ideally on several days in a year. Expansion and conversion factors are applied based on established stations along major roads that are supposed to have more frequent if not continuous counts. This methodology is how Annual Average Daily Traffic (AADT) is computed. Call it car-centric if you like but the methodology is very much applicable to bicycles as well. Peak hour counts for bikes are not enough and the peak hour factor for motor vehicles does not apply to bicycles (if this is to be used to expand/convert peak volumes to daily values). In fact, if you go into the math, there should be a peak hour factor for each type of vehicle considering each vehicle’s volume will vary differently over time. So yes, the solution here is to conduct bicycle counts according to how MMDA or DPWH counts vehicles and these should be done along several stations along major roads (e.g., those in the table above) to validate the MMDA counts.

More on this topic in the next post!