The New York City Department of Transportation’s Sustainable Streets Index (SSI) [pdf], released yesterday, is an annual progress report that takes stock of transportation trends and is a vital document in evaluating the utility of the city’s different transportation initiatives. In addition to recording overall trends in transportation—which, in yesterday’s report, included increased weekday subway ridership and increases in commuter cycling—this year’s SSI also assesses six safety, pedestrian, and bicycle improvement projects, two transit mobility improvements, two congestion reduction projects, and one public spaces project, all of which were implemented in 2010.

The SSI’s assessments of safety, pedestrian, and bicycle improvement projects indicate that these relatively inexpensive projects can have an exceptionally wide range of benefits, such as lowering injury crashes for motor vehicle occupants and pedestrians, decreasing speeding, increasing public and green space, increasing bike usage, and providing economic benefits for merchants located in the vicinity of the improvements.

The “Broadway: Union Square” project, for example—part of the chain of improvements NYCDOT has made on Broadway from Columbus Circle south—shows the multiple benefits of well-designed roadway improvements. Within the project area, ranging from Union Square north, NYCDOT made various pedestrian-friendly improvements including pedestrian islands, a parking-protected bicycle path, and a pedestrian plaza. Some of the project’s results include a “65% reduction in crashes involving motor vehicle occupants and [a] 26% reduction in total crashes involving injuries within the project area,” along with an increase in bicycle ridership on Broadway (up 18% on weekdays and 49% on weekends). Many store owners also reported that the new public spaces created by the project had helped business, and no store owner reported a decrease in business due to the open space. These results make clear that the project has improved conditions for all road users (bicyclists, pedestrians, drivers, car occupants) in the area.

The SSI also studied an instance of NYCDOT’s “Weekend Walks” program, which blocked cars from two blocks of Brooklyn’s Montague Street for three Sundays in September, 2010, allowing the local business improvement district to put on arts programming. Even though the program doesn’t allow for the exchange of money on the blocked-off street (with the exception of restaurants), over 75% of businesses reported an increase of foot traffic, while 86% reported that sales came in above their normal summer weekend average [pdf].

The economic benefits of these pedestrian-friendly street improvements will come as no surprise to the business community that has become the caretaker of a once-controversial pedestrian plaza in Jackson Heights. With so much more of New York City to improve, the SSI makes clear that there is more than meets the eye in a carefully planned and well-executed “safety project.”