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Revising the DPWH Design Manuals

A friend posted about the current initiatives in the US as they embark on revising their Manual on Uniform Traffic Control Devices (MUTCD). This manual along with AASHTO’s Geometric Design of Highways and Streets and their Highway Capacity Manual are something like the holy trinity for Highway and Traffic Engineers. These are also the main references for our DPWH for the manuals and guidelines we use in traffic and highways.

Here are a couple of articles calling for the revisions to reflect recent designs mainly from NACTO, which itself publishes guidelines for roads to be more inclusive rather than car-centric:

NACTO (May 2021) Modernizing Federal Standards: Making the MUTCD Work for Cities, https://nacto.org/program/modernizing-federal-standards/

NACTO (May 11, 2021) A Blueprint to Update America’s Street Manual, https://nacto.org/2021/05/11/a-blueprint-to-update-americas-street-manual/

We don’t have to pattern revisions after the MUTCD but then that requires that the DPWH through its Bureau of Research and Standards (DPWH-BRS) do its part in compiling, reviewing, studying and adopting materials from various countries, and developing suitable standards and guidelines for roads in the Philippines. Do they have to reinvent the wheel? Not so and they can still refer to the US manuals as long as again these are localised for our conditions and situations.

Vienna Conventions on Traffic and Road Signs

There are two important international conventions or agreements that the Philippines is a signatory to. These are the

Vienna Convention on Road Traffic (November 8, 1968):

and the Vienna Convention on Road Signs and Signals (November 8, 1968):

These are important as signatories are bound but the agreements on road traffic rules and regulations and standard signs and signal. I included the links to each agreement as they also include the exceptions taken by different countries such as Thailand and Vietnam declaring they will not be bound by Article 44, choosing to classify mopeds as motorcycles. Apparently, the Philippines did not declare exceptions or objections to any of the articles.

Are the traffic signs in the Philippines the same as those in the US?

This seems to be a simple question with a simple answer. And the answer is no. While the Philippines is signatory and has ratified the Vienna Convention on Road Traffic and the Vienna Convention on Road Signs, the United States hasn’t. The US also depends on their Manual of Unified Traffic Control Devices (MUTCD) that is by their Federal Highway Administration (FHWA).

Here is a nice article on Wikipedia for a comparison of signs in different countries:

https://en.wikipedia.org/wiki/Comparison_of_traffic_signs_in_English-speaking_countries

I recall an interesting project I was involved in where we audited signs along what was a new Subic Clark Tarlac Expressway (SCTEX). The signs from Clark to Subic followed international convention while the ones from Clark to Tarlac followed the MUTCD. We recommended that the latter signs be changed to international convention. I am not sure if the tollway operator changed the signs as I recall there were still US standard signs there particularly for speed limits.

On sharrows

The term ‘sharrow’ basically short for shared right-of-way and refers to lanes or roads that are ‘designated’ for all modes of transport including and especially non-motorized ones such as bicycles. It also refers to the lane markings. There have been some mixed experiences and opinions about sharrows; particularly referring to whether they are effective. Here’s an article from the director of technology of Smart Design, which is a strategic design and innovation consulting firm in the US that gives another opinion (an evidence-based one) about sharrows:

Anderson, J. (September 30, 2020) “Safer with sharrows?”, World Highways, https://www.worldhighways.com/wh12/feature/safer-sharrows

I guess the experiences in different countries vary according to several factors. Perhaps these include cultural factors that also relate to human perceptions and behavior? Education is also definitely a factor here aside from awareness. And we have to work harder on these and together, rather than play the blame game on this matter that relates to safety. How many times has the observation that Filipinos tend to regard road signs and markings as merely suggestions rather than guides and regulations?

On the efficiency of transportation – a crash course on transportation engineering concepts

There is an excellent article on the efficiency of transportation systems:

Gleave, J. (2019) Space/Time and Transport Planning, Transport Futures, https://transportfutures.co/space-time-and-transport-planning-1aae891194e5 [Last accessed: February 25, 2019].

It is highly recommended not just for academics (including students) but also for anyone interested in transportation and traffic. It’s like a crash course in transportation engineering with a lot of basic concepts in traffic engineering and traffic flow theory being presented for easy understanding by anyone. Enjoy!

Statement on the proposed emergency powers to solve transport and traffic problems

The National Center for Transportation Studies (NCTS) of UP Diliman submitted a statement to the joint Senate committees evaluating the proposal to grant emergency powers to the Philippines President in order to solve the transport and traffic problems in the country and especially in Metro Manila. Following is a copy of the one-page statement:

NCTS Statement on Emergency Powers 25Aug2016

TSSP 23rd Annual Conference Proceedings

The 23rd Annual Conference of the Transportation Science Society of the Philippines (TSSP) was held at the University of the Philippines (UP) Diliman last August 8, 2016. It was hosted by the National Center for Transportation Studies (NCTS), which for some time was practically inactive in its dealings with the society. The conference was a very successful one with more than 170 participants, mostly students from the undergraduate programs of Mapua Institute of Technology (MIT), De La Salle University (DLSU) and UP Diliman.

The Proceedings of the 23rd Annual Conference contains 22 technical papers, which I have already listed in a previous post showing the technical program for the conference. The link is to the current website of the TSSP hosted by NCTS. Those wishing to have copies of the papers may download them directly from the link. Meanwhile, those interested in the presentations should contact the authors. Their contact information are stated in the paper and it is ethical to get the nod of the authors for their presentation file as these still fall under what can be defined as their intellectual property. I am aware of people who tend to get presentation slides and then pass them of as their work when they use the slides or the data/information therein. There are proper ways for citations of references and sources but sadly such ways are not observed by many.

Some interesting (and required) readings on traffic engineering

Christmas breaks allow me to catch up on a lot of reading. The previous months comprising our university’s semester were spent preparing for lectures though I had to do some readings related to researches I am involved in. Browsing the net and social media, I came across 2 articles shared by an acquaintance. He is a very progressive planner who has extensively studied and written about the most relevant issues in urban planning, focusing on transport. A third article I found while reading one of the two. These were very interesting for me in part because they are thought provoking in as far as traffic engineering is concerned.

The author seems to call out traffic engineers in general but these articles should also be contextualized properly. The situations mentioned in the articles are to be found in cities in the United States and may not be applicable in other cities in other countries. Traffic engineers in Europe, for example, have been working on exactly the solutions being mentioned in the articles that would make streets inclusive and safe especially for pedestrians and cyclists. The same with Asian cities like Singapore and Tokyo.

In the Philippines, however, there is so much that we can learn from the articles. The mere mention of the design guidelines being used in the US betrays the flaws of highway and traffic engineering in the Philippines. The Philippines’ highway planning manual and other guidelines used by the Department of Public Works and Highways (DPWH) are heavily drawn from US references. Most highway and traffic engineers in the country are educated using curricula that use US textbooks and references. There are even civil engineering programs that use licensure exam review materials as their references! These exam materials are also known to be based on DPWH guidelines and manuals aside from problems “outsourced” or patterned after the Professional Engineer (PE) exams in the US. Few schools have progressive curricula that look to best practices that take into account the complexities of roads especially in the urban setting. Such ‘copying’ of American standards and practices in many cases do not consider Philippine (local) conditions and blind applications to our roads instead of proper adaptation often have lead to unsafe and inequitable roads.

The return of traffic signals at Katipunan

It’s been more than a decade since the MMDA implemented what was formally called the Grand Rotunda Scheme. To most, it will always be the U-turn scheme that was implemented all around Metro Manila. After seeing what seemed like success along roads like Commonwealth and Quezon Avenue, it was concluded that the U-turns were the answer to Metro Manila’s traffic woes or at least the part that’s blamed on signalized intersections. The perception by many at the time was that traffic signals were not working and caused so much congestion as evidenced by the long queues at intersections. This is not entirely false as intersections with in-optimal settings would definitely bring about congestion especially along corridors or networks where signals are not coordinated. It was, however, a generalization at a large scale and led to more experiments of opening and closing slots in order to determine which would be the most effective combinations. These experiments and their outcomes include drivers becoming more aggressive in order to maneuver ahead of others at the U-turn slots. Weaving has become the norm and in many cases have increased the risk of road crashes.

IMG09196-20140901-0625Traffic signals have been installed and the section of the median island has been removed across Ateneo’s Gate 3. This will become a three-leg intersections once again but I hope the signals will not favor Ateneo over through traffic along C5.

IMG09197-20140901-1339Traffic lights are already installed along the southbound side of Katipunan at the approach to the junction with Miriam College’s Main Gate. This will be a four-leg intersection as across Miriam is B. Gonzales Street that connects to Esteban Abada.

The signals are supposed to be operational starting September 13, which is a Saturday. Perhaps this is to try it out first during that weekend and for the MMDA to do some tweaks before the real deal that is traffic on Monday. But then how can you simulate traffic generated by the two schools in the area except maybe if there is significant enough traffic on Saturday? Did the MMDA or its consultants do some simulation using their computers and the VISSIM software they acquired many years ago? Or will we see more of the experiments as signals are fine-tuned according to the conditions along Katipunan?

We are hopeful that the signals along Katipunan will help improve the traffic along this very busy corridor. The results for sections of C5 from Libis (QC) to Ugong (Pasig) are promising and many people I know have told me that traffic has improved. Of course, this may also be partly due to the one-lane policy the MMDA has implemented for trucks. It’s never just one scheme or measure that will work wonders for Metro Manila traffic. It will always be a combination that will alleviate traffic woes in the metropolis. We’ll soon know what will become of traffic along Katipunan. We should, however, temper expectations at least for the 6:30 – 7:30 AM period during weekdays when traffic peaks in the vicinity of Ateneo and Miriam. The sheer volume of vehicles generated by the schools will overwhelm any system that is put up in the area. Nevertheless, for the rest of the day at least traffic flow should improve when signals are operational once again for Katipunan.

Countdown

Among the things you get to observe at signalized intersections are the behavior of drivers given the setting of the traffic lights. While the cyclic transition from red to green to amber and then to red again seems routine and possibly trivial to many, it is an opportunity for traffic engineers to examine how drivers react to the lights. Among the most notable behavior are common violations like beating the red light and occupying the area within the yellow box despite full awareness that the exit is already full.

Then there are the not so obvious but risky habit of some drivers to beat the green light. That’s when a driver anticipates the green light and proceeds to move prior to the signal and before the intersection is clear of any vehicles or pedestrians that may have been caught in the change in signals. It is a practice that increases the probability of a road crash occurring as the clearance interval for vehicles whose paths may be in conflict is drastically reduced. This is a habit of many drivers who are familiar with the sequence of signals at an intersection and who know when its their turn for the green light.

In most cases, drivers and pedestrians are unaware of the length of time available for them to cross the street or intersection. There are no indications for when the lights will change and only familiarity would allow for drivers or pedestrians to estimate when it would be their turn to proceed. In Japan, many intersections play music during that tends to speed up when the signal will be changing. This audible indicator allows for both the blind and the busy to know whether it is safe to cross the street and if there is enough time to do so. It is also something that is probably taught to children for them to more easily know when it is safe for them to cross the street.

There is another innovation to traffic signals that is surely welcome to pedestrians and motorists alike but which may also have its disadvantages. I am referring to the countdown timer, which provides road users the information about the lengths of green and red signals (Note: Amber or yellow is usually fixed at 3 seconds.).  From the perspective of energy efficiency, such information may allow motorists to turn off their engines, usually done when one practices eco-driving, resulting in fuel savings. Meanwhile, drivers of vehicles approaching an intersection may be able to tell if there is enough time for them to do so, and if there isn’t enough time they may be able to slow down their vehicles to stop at the next red light. Countdown timers may also be a helpful tool for enforcement as the timers establish that a driver should be aware of the time. Thus, a driver can no longer reason with the apprehending officer that he/she was not aware of the remaining time for movement.

Pedestrians may also benefit from the knowledge of available time to make a safe crossing. This information should ultimately reduce the need for running in order to completely cross the street. The photo below shows the new countdown timer installed for the southbound through movement at the Katipunan Avenue (C5) – C.P. Garcia Avenue intersection.

One possible disadvantage would be that aggressive drivers may still try to beat the red light by speeding up upon knowing what amount of time is available for them. Another disadvantage relates to beating the green light as even those unfamiliar with the signal sequence will have the information of how much time remains before they can proceed. Thus, many driver and riders start revving up their engines and push on their gears to anticipate the green signal. You can even imagine the countdown timer being used as if it were ticking towards to start of a race.

Despite the disadvantages mentioned, countdown timers should prove to be more beneficial than detrimental in most situations. In fact, countdown timers like the ones already installed at intersections in Bonifacio Global City should enhance traffic safety provided that these devices are fully complemented by enforcers who would flag down motorists and pedestrians who would attempt risky actions in relation to the timing device. Of course, from the research perspective there needs to be a scientific assessment of the actual impacts of countdown timers much like the studies already conducted elsewhere to determine and even measure the effects of these devices on both motorists and pedestrians. Only then can we truly say if they do enhance safety and promote more efficient operations at a signalized intersection.