Counting and Observing at Key Intersections
Due: Week 4
The first assignment is a group assignment, to go out and observe key street cross sections and intersections nearby in Cambridge. This assignment gives you a chance to observe and think about how people, different travel modes, infrastructure, and neighboring land uses interact in a real, live place. You will not only look and see what is going on, but also start to become familiar with how “little numbers” translate to real-world conditions: what does 800 cars/hour look like vs. 800 people riding the T, and what impact do these differences have on the nature of the urban scene? You should become familiar with basic ideas like level of service, saturation flow rate, capacity, speeds, flow, and mode share (see Meyer and Miller, Chapter 3). We want you to think about how you measure and what you measure, and what impact this has on the transportation planning process and built outcomes.
This assignment will be done in teams and submitted as group work. You will be divided into teams based on your diversity of skills and backgrounds.
Observation and Data Collection
Each team is to count, by direction and turning movement, automobiles, buses, taxis, TNC vehicles, bicycles, pedestrians, trucks, and trains. But you are also to estimate how many people are using these different vehicles, to get a sense of the relative numerical strength of each user group. You are to count at one morning peak hour and one evening hour between 8PM and 9PM. If we have enough students, each individual student should only need to do two hours. You are to count the old fashioned way, just to give you a feel for how reliable the data collected was; but you should also supplement the hand counts with taking a video on your phone, so you can check your count and will have a record that may pick up nuances that you might have missed. Please be sure to count in groups, both because there is too much for one person to successfully count, but also for safety. Especially in evening hours, please be sure that you feel safe and have company.
What to Count
A detailed description of what/where to count for each location is attached (see end). Key intersections have been marked with blue circles, but for context you should make observations of the neighborhood, street network, and traffic flows of a bigger surrounding area (exact scope is up to your judgment, but we recommend radiating out 1-2 blocks). Before you go out and start counting, take a look at the 19 step planning process from lecture 1 and think about what type of data you think would be useful for understanding current conditions and making planning decisions, and how you can best represent and communicate the reality ‘out there’ to your audience.
So that you observe the place from a multi-modal perspective, count all the major transportation modes passing through the site: private vehicles (cars, trucks, motorbikes), taxies and Ubers/Lyfts (if identifiable), transit vehicles, bikes and pedestrians. For buses and trains, a rough estimate of onboard passengers (e.g. “75% full” - for reference, regular MBTA buses have 39 seats, and a policy maximum of 54 total passengers) may be all you have time for. For cars, try and estimate the occupancy. If turning or transfer movements (from one street or mode to another) appear significant, you may wish to gather data on these as well, especially if heavy transfer volumes or blocked turning movements cause backups.
Tips on Counting
Your sites will be complex and there will be a lot going on (that’s why we’ve chosen them)! We recommend:
- Conducting your traffic counts in two 20-minute intervals, taking the average of the two, and scaling-up to hourly values. Please be sure to obtain at least two samples to guard against sampling error.
- Dividing up the major routes and directions at your site and count all the travel modes applicable. Depending on how heavy the traffic flow is, you may be able to count multiple modes at the same time.
- Taking videos (using smartphones or other devices) of the scene, which allows you to count in slower motion, pause, rewind, and re-count if needs be afterwards. (Spoiler: this is how traffic is counted in the real, professional world.)
Having completed your counts and observations, each team needs to write a team report for the location of no more than 12 pages double-spaced (excluding figures, tables, and appendices).
In your report, explicitly address the following:
- Site introduction and paper introduction
- What is the site’s regional context vs. local function?
- Briefly research history of the intersection
- How has transportation influenced the development of this site, or vice versa?
- Stakeholders: Who are the stakeholders and constituencies affected by transportation at this site? Who owns what? Who uses what? Who is exposed to transport pollution or safety hazards?
- Analysis (see below for more detail)
- Major travel patterns: What major travel patterns do you observe? How can you explain these patterns? Think about the generators and attractors of people.
- Problem areas: What existing and emerging problems do you identify?
- Do you have any recommendations (very briefly) on how these problems could begin to be addressed?
The format and organization of the document is up to you. Each team will submit one report which should reflect a group effort.
Your report should discuss Step 2, 3, and 5 of the 19-step process, and you can spend a little time on suggestions for Step 7 (developing solutions). YOu cannot necessarily do a complete job, but you can identify what other actions and data gathering is necessary to do a complete job.
We expect you to do more than just give a simple summary of the ’little numbers’ that you collected. There is no hard-and-fast way to tabulate and present your data; use whichever methods you feel ar most appropriate. Interpret your data and see what ‘story’ it tells about your site. Think about how different ways of measuring and analyzing can paint a different picture. Questions you might answer in telling this ‘story’:
- What are the dominant flows for each mode? (i.e. where are most people traveling?)
- Who and what activities aren’t happening or being measured?
- How many people use each mode, and how much space/time is allocated to each mode? How can all these users share the space?
- Do the most numerous users of the street change over different periods of time?
- What are major conflict points?
- Which are the most stressful hours, for each group of users?
- Who is using the curbs?
- Do some streets really belong to a network of parallel streets, all of which need to be observed?
- Can problems be solved with a bucket of paint?
Carefully consider how effective diagrams and explanatory text can help answer these questions.
Your team should be ready to do a ten minute, informal presentation during recitation. To allow for questions and answers, each group should have twenty minutes, so we can see four to five groups present.
Your paper will be graded (as a group product) based upon the integration and effective use of concepts in the readings, lectures, and discussions. In addition, your paper will be evaluated based upon the clarity of presentation (clear writing, thoughtful analysis, effective argumentation). Additionally:
- Please limit the written portion of the memo to the equivalent of no more than 12 double-spaced pages.
- Figures, tables, or illustrations are not required but you are encouraged to use them if you think they will be useful; they will not count towards the page limit.