News and Updates

The Vermont Agency of Transportation is in the process of updating their guidelines for conducting Traffic Impact Studies. These studies determine what type, location, and relative impact development has on the transportation system in the State. I have compiled some comments that I have on the proposed guidelines.

You can find the proposed guidelines here: [pdf]

The primary issue at hand is the idea of urbanization. I am a Vermonter - a 7th generation at that - and love my state. I know it has changed substantially during the lifetime of many of the ‘oldtimers’. Due to many reasons, but fundamentally, I feel by the segmentation and breakdown of our ‘rural’ way of life. In the past we have been fortunate to maintain our very traditional New England lifestyle of villages and town centers surrounded by farm and forest. However, highways have been built bringing additional money and opportunity to the hills of Vermont, we have been able to support ourselves by living farther away from our workplace. Thereby spreading out.

This has had severe impacts on our lifestyles, community spirit, and not to mention transportation systems. As a way to curb the sprawling effect of our development, I want to encourage more people to live again in a denser village center, perhaps urban, environment.

I feel that our current policies in the transportation world have worked against that desire. Creating perverse incentives to develop on green fields, spreading out our development away from our village centers. These comments, though brief, are an attempt to spread some light and start a discussion of this phenomena.

-Jon

Jon Slason comments:

1.) We should not paraphrase in a document like this. It becomes a legal document used throughout the permitting process. Anytime a paraphrased definition is used, it weakens the meaning of the term. When referring to terms we should be precise and use exact traffic/transportation engineering terminology.

2.) Examples should also be removed. A TIS guideline document should present the traffic/engineering professional a document in which to reference the applicable standards that Vermont uses – not educate them on their job. If examples are placed to provide guidance to developers or lay persons, then a second document should be developed that could be an appendix perhaps.

3.) V/C ratio should be mentioned and described how the State uses V/C ratios. What V/C ratio is acceptable?

4.) How does development occur when traffic impacts already congested intersections? What portion of mitigation is the new traffic responsible for? The State of California for instance uses a very unique, though rather impractical, policy that states if the intersection is LOS F new developments can only increase delay by 2.0 seconds overall. This lead to a lot of very specific signal tweaking as mitigation which would reduce delay but that probably never truly occur in the field.

5.) Allowance for urban growth in the LOS policy. Currently due to traffic constraints (one among many other reasons) many developers shy away from developing in brownfields, previously developed areas, or urban areas, because of a LOS policy that does not allow for congestion. Instead, this pushes development to the edge of an urban area into areas either where capacity currently exists or where adding additional capacity is relatively cheap. Many of our national beloved urban centers would not be built if they were required to document that their transportation impacts would not impact nearby intersections worse than LOS C or D. The benefits of an urban transportation system are obvious and I am sure, well known to you.

Younger urban areas confront a chicken and egg scenario where they generate too much traffic to be permitted but are often not dense enough to reduce VMT (use of transit, walking, biking, etc). We need a LOS policy that would allow designated growth centers (designated by the Vermont Legislature) to have a separate LOS policy. This would allow these growth centers to determine their own policies and mitigation strategies for impacts, such as the development of transit O&M funds, payment in-lieu of systems, etc. I mention the growth centers, because it would be unwise to let every development claim they have this right to allow for poor LOS simply because they are in a capacity constrained area.

I would suggest that based on the notion that congestion is not always a bad thing – this kind of policy be investigated further. High levels of congestion can be conducive to slower vehicle speeds and actually encourage more biking and walking. I feel that our traffic policies as a profession has severely hampered our ability to develop tight-knit urban systems such as been developed in the past.

6.) Unsignalized intersections: If I read the language as now stated in the new LOS Policy – it can be interpreted (by placing that last sentence into the document) that if a side street experiences LOS worse than LOS “D” (LOS E and F) then the intersection is unsafe. This is a statement that could lead to potentially many legal issues because of the wording in Act 250 Criterion 5 and 9. I simply want to note my hesitation to including that last sentence.

From an anecdotal perspective, on higher speed, uncongested roadways, it could be very true that LOS D is a proper safety threshold. However, on slower speed roads or very congested highways, poor LOS may not necessarily denote “unsafe” conditions. I would be happy to see some conversation again on V/C ratios playing a part in unsignalized intersection operational analysis.

Thank you for letting me submit my comments. These comments represent my views only and not those of RSG or any other organization that I affiliate with.