- Assuming you can get a driveway or curb cut wherever you want.
- Assuming you'll get a traffic signal at your development's main intersection.
- Assuming a government agency will pay for the infrastructure (signals, turn lanes, medians, etc.) needed to get traffic smoothly in and out of your development.
- Ignoring the traffic concerns of your neighbors.
- Assuming one of your consultants (architect, landscape architect, civil engineer, traffic engineer) is designing a site plan that will have good internal traffic circulation.
- Assuming your traffic engineer is a good public speaker and will represent you well in public hearings.
- Assuming a traffic study can be done in a few days.
- Assuming all traffic engineers are good at developing a phased mitigation plan that will protect the motoring public while considering your bottom line.
- Using a consultant traffic engineer that is not respected by the public agencies who will be reviewing their traffic study.
- Assuming traffic studies are straight science - many assumptions go into a traffic study and politics are often involved with traffic issues (politicians rarely question the size of a recommended sewer pipe, but they often have an opinion on traffic recommendations).



Great list! A couple more egregious mistakes I've encountered to some degree:
"calling your traffic consultant after you've committed to building footprints"
or
"fretting excessively about whether 5 versus 10% of your traffic accesses the site via a particular direction, while completely overlooking how it distributes once on your private property"
Posted by: Jay | June 11, 2009 at 08:09 PM
Jay -
Great additions. I would love to turn this into a top twenty list of there are other thoughts out there.
Mike
Posted by: Mike | June 12, 2009 at 09:10 AM
You hit the nail on the list.
In reference to #5... Not having a traffic engineer involved in the site plan at all.
As far as I am concerned, all city's should require that all site plans be sealed by a traffic engineer in addition to the Site/Civil engineer.
Also trying to nickle and dime over pro-rata share while tying the project up for months.
-Brian
Posted by: Brian | June 12, 2009 at 09:53 PM