Stop Chicken Little: The Truth about Traffic Calming  in Portland, Maine



 Stevens Avenue

Stevens Summary



Air Quality

Curbs, Medians, Tables

Pedestrian Accidents

Vehicle Accidents



Muskie Institute

Legal Aspects


MDOT data

SAP Lies


Opponent Petition

ATC Brochure

 Kane letters


Deering Oaks

Brighton Avenue

Capisic  Street


Stop Signs



85th percentile Speed measurement denoting how fast 85% of the vehicles in an area are going. The speeds of 100 cars are measured to get this number. E.g: Assume a speed limit of 30 MPH.  If the fastest speed of the slowest 85 is 34 MPH, then the 85%-ile is 34 MPH.
This is not to say that all 85 are doing  34 MPH.
84 cars could be going 5 MPH, with the 85th doing  34 MPH, and the 85%-ile would still be 34 MPH.
Speeding Vehicular motion in excess of the posted speed limit.
Speed table
(from Traffic
Speed tables are flat-topped speed humps. Speed tables are sometimes long enough for the entire wheelbase of a passenger car to rest on the flat section. Their long flat fields give speed tables higher design speeds than speed humps


  • They are smoother on large vehicles (such as fire trucks)
  • They are effective in reducing speeds, though not to the extent of speed humps.


  • They have questionable aesthetics, if no textured materials are used;
  • Textured materials, if used, can be expensive; and
  • They may increase noise and air pollution.
  • They slow emergency vehicles response.
Speed hump

(From Traffic
Speed humps are rounded raised areas placed across the roadway. They are generally 10 to 14 feet long (in the direction of travel).  The profile of a speed hump can be circular, parabolic, or sinusoidal. They are often tapered as they reach the curb on each end to allow unimpeded drainage. Profile usually based on a 750-foot circle.


  • Speed Humps are relatively inexpensive
  • They are relatively easy for bicycles to cross if designed appropriately
  • They are very effective in slowing travel speeds.


  • They cause a "rough ride" for all drivers, and can cause severe pain for people with certain skeletal disabilities
  • They force large vehicles, such as emergency vehicles and those with rigid suspensions, to travel at slower speeds
  • They may increase noise and air pollution
  • They have questionable aesthetics.
Speed bump Various in size, usually about a foot deep, 6 inches high, and any width. What is found in parking lots. Illegal on all public roads in the U.S.
bumpout Also known as chokers, are curb extensions at midblock locations that narrow a street by widening the sidewalk or planting strip.
chicane Chicanes are curb extensions that alternate from one side of the street to the other, forming S-shaped curves.
median Median barriers are islands located along the centerline of a street, They sometimes continue through an intersection so as to block through movement at a cross street.
neck-down Neckdowns are curb extensions at intersections that reduce the roadway width from curb to curb.
 FHWA Federal Highway Administration :The federal organization that sets  safety, construction, and policy regulations for the nations highways, of any size. .


 AASHTO American Association of State and Highway Traffic Offices
NHTSA National Highway Transportation Safety Administration : the agency directs the highway safety and consumer programs established by the National Traffic and Motor Vehicle Safety Act of 1966, the Highway Safety Act of 1966, the 1972 Motor Vehicle Information and Cost Savings Act, and succeeding amendments to these laws.
MDOT Maine Dept. of Transportation.
DEP Department of Environmental Protection : Maine agency whose job it is to promote sound environmental policy and programs
EPA Environmental Protection Agency
NEPA National Environmental Policy Act.
CMAQ Congestion Mitigation Air Quality a federal program that funds air quality improvement projects.
MTROBA Mayors Taskforce Report On Brighton Avenue
ITE The Institute of Transportation Engineers is an international educational and scientific association of transportation professionals, 17,000 members in 90 countries, who are responsible for meeting mobility and safety needs.
Together with the FHWA, they set standards for the nations roads.
Generally ignored by the Portland City Council.
DCNA Deering Center Neighborhood Association : local group whose ostensible purpose was to improve the Dering Center neighborhood.
SAAC Stevens Avenue Advisory Committee : ad hoc group of people who were telling the DPW what to do via their mouthpieces, Tom Kane and Jim Cloutier.