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Category Archives: Traffic flow

On the opposition to “complete streets”

I recently read an article about the opposition to road diets in California, USA:

Tinoco, M. (2018) “How to Kill a Bike Lane”,, [Last accessed: 5/20/2018]

So far, we know that at least three cities are progressive enough to implement road diets including Marikina City, Pasig City and Quezon City. Iloilo doesn’t count yet since their bike lane was constructed along the very wide Diversion Road. Our recommendations for Tacloban, if implemented by the city, will probably result in the second most comprehensive application of road diets/complete streets in the Philippines after Marikina, which implemented their bikeways network almost 2 decades ago. There are sure to be many who would be opposed to such schemes as many still have the view that streets are for motor vehicles. This car-oriented thinking is something that will be a challenge to advocates of people-oriented transportation systems. Hopefully, many can learn from experiences here and abroad on how to reclaim space for people leading to safer and more inclusive transport for all.

Proposed downtown traffic scheme for Tacloban City

The team from the National Center for Transportation Studies of the University of the Philippines presented their recommendations for the traffic scheme in downtown Tacloban City last May 4, 2018 in the city’s Traffic Summit cum City Development Council (CDC) meeting. I am sharing the image showing the proposed traffic circulation and other features for the proposed downtown scheme below:

The scheme calls for a reduction in on-street parking; restricting such to one side of the street only and where applicable. That is, on-street parking is not allowed where there is already off-street parking along establishments, where there are driveways, and within one or two vehicle length from intersection corners. There will also be designated loading/unloading areas for public transport so parking is also prohibited there.

A couple of important features in the scheme are the enhancement of pedestrian facilities, particularly sidewalks, and the introduction of bicycle lanes. These are more clearly shown in the cross-section examples included in the map. Note that for other streets where there are no designated bike lanes indicated, it is assumed that lanes will be shared with motor vehicles. This is an application of the concept of shared right of way or “sharrow” as it is also termed. The scheme is contextualised along the lines of “people-oriented” transport rather than “car-oriented”, and hopefully would lead to a more walkable downtown area and encourage more people to use bicycles. This promotion of active transport should also lead to a healthier city. I will post about the transport plans prepared for the city in future articles here.

On the Pasig HOV traffic experiment

Someone shared a post about a traffic scheme they will be implementing along Julia Vargas Avenue in Pasig City. The proposal is for the avenue to have a high occupancy vehicle (HOV) lane where vehicles with 4 or more occupants are to take one lane and all other vehicles the other. I am not entirely sure about the objective other than to promote high occupancies for vehicles. However, it would be nice to see how travellers will be behaving (e.g., complying) and how Pasig (with MMDA?) will be enforcing this scheme.

This is what a segment of Julia Vargas currently looks like with 2 wide lanes designated for motor vehicles (separated by the solid yellow line) and one narrow lane for cyclists (adjacent to the shoulder):


The intent is good but as a major link the scheme can be quite confusing especially for those who are not necessarily frequent users of this road. I assumed the yellow line was painted by the DPWH but it seems it was by Pasig. Perhaps they should have removed the old markings? Or maybe better if they rationalised the carriageway width to accommodate 3 lanes for motor vehicles and 1 wider lane for bicycles? From the photo above, it appears to me that it is possible to have 2 narrow lanes for general traffic and one wider lane for HOVs (in this case defined as having 4 or more occupants) and public utility vehicles. This configuration maximises the capacity of the road while having a the “best” lanes allocated for HOVs and bicycles.

I wish them success on this social experiment. Perhaps there can be valuable learnings from this including the need for connectivity to other links as well.

Congestion along C-6 and potential for a public transit corridor

We begin February with a post on a road that’s becoming more popular as a major (as opposed to alternate) route to Bonifacio Global City (BGC) and Makati CBD – Circumferential Road 6. I took the following photo at the approach to the Nagpayong Bridge that is current has only 2 lanes (1 per direction). Another bridge is being constructed along the existing one that will increase capacity for the Pasig River crossing to 2 lanes per direction. This is similar to what was done to the Barkadahan Bridge  crossing the Manggahan Floodway in Taytay, Rizal.

The volume of road vehicle traffic is steadily increasing along C-6. The adjacent land use offers a lot of potential for development (hopefully planned) that will feed more traffic along what will become a major thoroughfare in the near future. The land I am referring to are the reclamations on the side of Laguna de Bai along C-6 that are under the jurisdiction of Taguig and similar developments on the opposite side on what was once swampy or marshlands. One wonders if Taguig has a plan for all this or if the city is turning a blind eye and just letting developers do what they want. Most seem to be residential subdivisions and industries-related with a sprinkling of mainly small to medium-sized commercial developments.

Again, I think national and local governments should consider making this a public transport corridor by introducing formal public transport in the form of a scheduled bus service stretching from, say, Bicutan Interchange to Taytay Public Market. The demand along this corridor is steadily rising and only a better connection to C-5 limits an even steeper increase in traffic volume along C-6. The time is now in order to condition commuters about the system and to the unwanted congestion experienced along major roads in the metropolis.

On car following

We teach our students about car-following theory and applications in our transportation engineering courses at the undergraduate, graduate and post-graduate levels. This is an important part of traffic flow theory and essential in understanding and modelling traffic flow/ behaviour. Among its applications is in the development of simulation models such as those that are now commercially available like VISSIM and CUBE-DynaSim and the older but still very useful TRAF-NetSim. Car-following theory allows for a more accurate simulation of real-world traffic behaviour considering the many parameters describing traffic flow as well as the assumptions that need to be in place for various scenarios.

Here’s an interesting article that’s basically about car-following, specifically mentioning the proper (ideal?) spacing between vehicles and how such discipline can lead to less congestion along our roads.

Simon, M. (2017) Math says you’re driving wrong and it’s slowing us all down, Wired, (Last accessed: 12/17/2017).

The need for speed (limits)?

My social media newsfeed regularly contains updates being posted by various entities about transport and traffic in Metro Manila and across the Philippines. Among those I regularly see are posts on road safety and interesting to me are the frequent posts on legislating speed limits at the local level. These are in the form of city or municipal ordinances that are supposed to strengthen, supplement and/or clarify speed limits that are actually already stated in the road design guidelines of the Department of Public Works and Highways (DPWH). These limits apply not only to national roads but to local ones as well. However, their effectiveness may be limited or reduced by the absence or lack of signs, markings and, most importantly, traffic law enforcers who are supposed to monitor traffic and apprehend those violating rules and regulations.

While there is a need for defining and clarifying speed limits perhaps in the form of local legislation, I believe the more urgent matter is the implementation and enforcement of laws. It has often been mentioned that we already have so many laws, rules, regulations and the truth is we do, and may not need more. One really has to go back to the basics in terms of enforcing these laws and that means enforcers need the knowledge and tools to be effective in their work. There is an opinion that many enforcers are not knowledgeable about many rules and regulations and therefore are prone to just focus on a few including violations of the number coding scheme, truck bans and the much maligned “swerving”. You do not often seen apprehensions for beating the red light, beating the green light (yes, there is such a violation), speeding, or “counter-flowing” (or using the opposing lane to get ahead of traffic in the correct lanes). There are also turning violations as well as those involving vehicle (busted tail lights, busted headlights, busted signal lights, obscured license plates, etc.). More recently, there are anti-drunk-driving laws that also urgently need proper implementation.

I think the current work that includes sidewalk clearing operations and anti-illegal on street parking of the Metropolitan Manila Development Authority (MMDA) is one good example of going back to the basics. These address the necessity of clearing space for both pedestrians and vehicles; space that have been constrained by obstacles that should not be there in the first place but so often have gotten the blind eye treatment. Going to the “next level” though requires tools such as speed guns,  high speed cameras at intersections, and instruments for measuring blood alcohol levels in the field (breath analyzers). And these require resources for acquisitions as well as capability building in the form of training personnel to handle equipment. No, I don’t think we need more laws, rules and regulations. What we urgently if not direly need is their proper implementation to effect behavior change that will improve both safety and the flow of traffic.

Tacloban’s one-way traffic scheme

I was in Tacloban City last month and got to meet former participants to our training program who are working for their Traffic Operation Management Enforcement and Control Office (TOMECO). Among the topics of discussion was the traffic scheme for the central business district (CBD). Last year, the city had implemented a one-way traffic circulation scheme for the CBD as shown in the following map in the traffic advisory released by the city:

The city had to ease up on the one-way scheme, retaining it for the northwest-southeast directions and reverting to 2-way flow for the northeast-southwest directions. This decision was apparently due to the feedback the city got from various stakeholders about travel times and distances becoming longer due to the one-way scheme. This needs to be verified by collecting data pertaining to typical routes taken by vehicles, private and public utility, in order to get from an origin to a destination (e.g., from home to school). This can be simulated or estimated using field data (travel time surveys). We intend to use both as we make an assessment of the scheme and formulate recommendations for the city.