• Introduction
  • Why we measured the surfaces of the city's streets
  • How we measured the city's streets
  • The two indicators of street smoothness
  • The broader purpose of this work
  • Results & Findings (1998 and 2001 Reports)

    In 1998, the Fund for the City of New York's Center on Municipal Government Performance released results of an unprecedented research project that uses state-of-the-art laser technology and citizen input to produce the first reliable, objective ratings of the smoothness of New York City's streets. A year earlier, test engineers drove a car equipped with profilometers that counted and measured every dip and rise encountered from potholes, bumps, misaligned utility covers, uneven repairs and more. We measured over 670 miles of New York City's streets, covering all 59 community districts. The extensive data collected were then analyzed to produce two indicators that New York City residents identified as meaningful to them: a Smoothness Score and a Jolt Score. In 1999 we conducted another citywide survey. The findings of our studies are published in two volumes and are summarized and available here.

    Why we measured the surfaces of the city's streets
    We started measuring the smoothness of the city's streets in 1997 after learning through focus group research that one way people rate the performance of their city government in general is by how well the city's streets are maintained. To many people, street maintenance is a most visible example of local government performance. People thought the city could do a better job. The presence or absence of roughness and bumps on the streets was key to their assessments. The public and government did not have objective information on this subject. We fill that information gap in these reports.

    Although it was initially surprising to us that an early project of the Center on Municipal Government Performance would be to measure and report on the smoothness of city streets, the pervasiveness of people's comments reminded us that roadway maintenance has been a fundamental responsibility of government going far back into the history of cities. For example, frescoes dating from the 14th Century on the walls of Sienna, Italy's city hall depict "The Effects of Good and Bad Government." Good government is shown as being just to its people and having navigable streets. Bad government is otherwise.

    There are other compelling reasons to work toward smoother streets. Bumpy, uneven streets precipitate pedestrian and vehicular accidents, impede traffic flow, cause driver fatigue, cause damage to vehicles and shorten their life.

    How we measured the city's streets
    The findings presented in the first and second reports are the result of carefully designed surveys to provide reliable information to the public and government on this topic. We initially learned about how the public rates government performance when we listened to New Yorkers from various parts of the city in focus group sessions. Later on, we took members of focus groups on rides over city streets to determine what degrees of roughness they considered acceptable.

    The surveys cover approximately 670 miles of the city's streets, measuring randomly selected groups of adjoining blocks in all 59 community districts throughout the city, simulating the way a driver would ride along the city's streets. The surface of the streets were measured by laser-scanning devices, known as profilometers, which are attached to a test car and produce objective, reliable and accurate measurements about variations on the surface of the streets. Profilometer readings are then converted into standard roughness and bump indices, using methods developed and employed in studies sponsored by the World Bank and the Boeing Corporation. Details about our methodology appear in the Technical Appendix. (PDF will open in new window).

    The two indicators of street smoothness
    We introduced two measures of street smoothness that the public uses to rate the streets: a Smoothness Score and a Jolt Score.
    • The Smoothness Score is the percentage of blocks rated "acceptable." It measures the roughness/smoothness of the surface of the street over a certain distance. It takes into account all variations in the surface and reports roughness for all reasons, including an overall "washboard effect." Smoothness Scores are weighted by length so that comparable results are produced. The Center asked New York City drivers to categorize the objective data. In focus groups, they identified four types of streets and named them: "good" and "fair," which they considered acceptable streets, and "poor" and "terrible," which they said were unacceptable. We report the data gathered by the profilometer in those categories.

    • The Jolt Score is the number of significant jolts encountered per mile. It is a count of street irregularities, be they from holes, ridges, uneven repairs, bumps, plates, utility covers, etc. that produce a certain, severe jolt when a car encounters it.

    The broader purpose of this work
    As an organization created to help improve the quality of life in New York City and concerned about the need for the public and government to communicate effectively with one another, the Fund for the City of New York, through its Center on Municipal Government Performance, has been creating ways in which the public's views of government performance can be incorporated into measurements that can be discussed and tracked by the public and government. We hope that our work will encourage government to include the public's perspectives into its planning and reporting. And we hope that, in this case, government will inform the public about matters that are relevant to improving the streets. We think that the public then will be served by being better able to understand, assess, and, when they feel it necessary, influence the way government is performing.

    In the 1970s, long before other cities considered producing and disseminating information about the way its agencies function, New York City led the way by enacting in its Charter the requirement that two Mayor's Management reports be issued every year, detailing, among other things, actual performance and performance goals and measures for each city agency. Semi-annual reports have been prepared and submitted to the City Council and made available to the public ever since. The reports contain narrative, graphics, operating statistics and budget information that can be useful to city managers and of interest to the general public. Building on this singular achievement, we think that the next generation of performance measures must also include the public's perspectives whenever possible. The public needs to be informed about how the data are collected, can sometimes be involved in the collection of data themselves, or otherwise be assured of the relevancy and accuracy of the data.

    When people and government have reliable, relevant, information they both can trust about city government's activities, they can enter into informed dialogues, which we hope will dissipate distrust and cynicism. Our further hope is that understanding, mutual respect and improved performance will follow.

  • The Fund's Center on Municipal Government Performance is supported by grants from the Alfred P. Sloan Foundation.

    © 2008 Center on Municipal Government Performance, Fund for the City of New York