Mike on Traffic

Trip Generation, 8th Edition Spreadsheet

Back in November I posted about the freshly printed 8th Edition of Trip Generation.  I received several requests for trip generation data, so in an effort to help the industry we've put together a spreadsheet with all of the a.m., p.m., and daily trip generation rates.  With the few land uses where we feel it makes sense to use the trip generation equations, we include those in addition to the average rates.  The spreadsheet also includes pass-by rates from the 2nd Edition of the Trip Generation Handbook.  Here it is Download TripGeneration8thEdition.  Details about the spreadsheet are contained on the top and bottom, so scroll all the way down before you ask me any questions.

Caveat emptor -  we have done our best to assure the data is accurate (since we plan on using the spreadsheet ourselves).  If you find any errors, please let us know and we'll post the corrected spreadsheet.

Special thanks to the apprentices - Mike Bultman, Joe Collins, Jenni Hattervig, and Kirk Pettis.  They put in the time with the data entry and quality control. 

Traffic Presentations at Public Hearings

Traffic is often a scapegoat used by neighbors at public hearings (in front of county boards, city councils, planning commissions, etc.) to try to kill a proposed development project.  It is a favorite tactic used by those opposed to new Walmart stores (at least the dozen or so public hearings I have attended for my Walmart traffic studies). 

I attended an emotional public hearing with a developer for his proposed strip mall/gas station development a few weeks ago where traffic issues were raised.  Through a lot of practice, I have honed my presentation skills so I am ready to speak up for my clients at public hearings.  Two big lessons - tell stories to make the statistics easier to digest and know when to stop talking.

Brief tangent, but I promise to circle back -

I just finished reading Made to Stick, which I highly recommend.  At the beginning of Chapter 5, Dan and Chip Heath talk about research done that proves people will donate more to a single person than to an entire cause.  The researchers at Carnegie Mellon set up a donation letter asking people to donate to Save the Children, a charity that helps kids in Africa.  A second letter described a little girl in Africa named Rokia and then asked for donations for Rokia.  The average donations for the Rokia letter were more than double that of the Save the Children letter. 

The Carnegie Mellon researchers did a subset analysis with the Rokia letter.  They asked half of a group, "If an object travels at five feet per minute, then by your calculations how many feet will it travel in 360 seconds?"  The other half of the group was asked, "Please write down one word to describe how you feel when you hear the word 'baby'."  Then they gave everyone in the group the Rokia letter and asked for donations.  The "baby" group gave about the same amount as the previous Rokia letter donators.  Those who did the math gave about half the amount of the previous Rokia letter donators.

Here is the conclusion from the Heath's, "These results are shocking.  The mere act of calculation reduced people's charity.  Once we put on our analytical hat, we react to emotional appeals differently.  We hinder our ability to feel."

TAKEAWAY - emotion is the enemy of a traffic engineer making a presentation at a public hearing.  Under most scenarios, we want the city council to make a logicial decision based on our work.  So, traffic engineers (and developers?) should warm up at a public hearing with some subtle calculations to diffuse the emotions in the room.

Spack Consulting Website Launch

Check out our completely redesigned website, www.SpackConsulting.com.  Bob and Mark at DKS Systems did a great job for us and I am proud of our new internet home.

One Ways to Two Ways - Hennepin and 1st Avenues in Minneapolis

The City of Minneapolis is converting Hennepin and 1st Avenues from a one way pair back to two way streets in a back to the future type move (check out the Minneapolis project site).  The two way streets were converted to a one way pair in 1980 because of air quality issues.  Business owners along the corridors have lobbied city politicians for years to convert the streets back to two way streets because they feel the one way streets limit their vitality and access. 

The politicians acquiesced against the recommendations of several traffic engineers.  The area will become more congested and going from one way to two way streets will double the number of conflict points for potential crashes. The air quality is expected to pass standards though.  The conversion will only take minor construction at a few intersections, the modifcation of the traffic signals along the corridors, a chip seal, and re-striping (painting).  The conversion is expected to be completed in early November.

Bike boxes will be incorporated along 1st Avenue, which will be new for the area.  New for the U.S. will be the parking lane configuration along 1st Avenue.  The cross section (from the City of Minneapolis) shows the outside travel/parking lanes.  During the middle of the day, the outside lane will have metered parking.  During the evenings and rush hours it will be a travel lane.  This isn't new, but having a bike lane between the parked lane and the sidewalk is new.  Montreal, Canada and several European cities have this configuraiton.  But based on the city's research, this will be new in the U.S.  I hope to see a before/after study as part of the project.