Amsterdam experiment in mixing pedestrians, trams and bicycles, The

Institute of Transportation Engineers. ITE Journal, Aug 1999 by Zacharias, John

The street is also the major traffic carrier in an area of four- to six-story buildings with high site coverage, even though the street itself is only 12 meters (m) wide. The Leidsestraat is lined with clothing, houseware and gift shops as well as small restaurants. The transversal streets also are lined with restaurants, which generate considerable traffic in the evenings. The Leidsestraat itself empties into the Leidseplein, one of the most important entertainment centers in the city and the junction of several tramlines, bicycle and car routes. During the peak period from noon until 3 p.m., pedestrian volumes vary from 3,000 to 4,000 persons/hour (h). Although the great majority of pedestrians are natives, tourists form an important minority, more for their conspicuous behavior than for their actual numbers. Three tramlines pass through these streets at headways of about two minutes, for a carrying capacity of 2,800/h. The cyclist volume varied between 200 and 300/h.

The street is demarcated by a single, overlapped tramtrack in the center, set in asphalt and bordered by a gutter grating. Both sides of the grating to the building faces are paved in brick. These wide strips of brick are divided into two parts, the inner building edge being finished in a variegated and unevenly laid brick while the central strip is flat and even (Figure 2). Part of the rough brick surface also is used for store displays, bicycle parking and refuse bins. Pedestrians are concentrated in the flat brick area but also stray onto the tramtracks when the density is high. Up to half of the bicycles follow in the wake of the tram, share the asphalt strip between the rails or veer between groups of moving pedestrians. Faster moving pedestrians usually choose to venture into the tramtrack area, moving out of the way of oncoming pedestrians, cyclists or trams (Figure 3).

The first impression of the Leidsestraat from the raised bridge portions over the canals is that of a chaos of movement. Movement in both dominant directions is heavily intermixed, with additional movement from side to side of the street. Through the center at two-minute intervals trams pass alternately in both directions. Bicycles weave through all of this movement. Dozens of collision accidents appear ready to happen at any one moment although very few are witnessed (none in several days of observation).

RESEARCH RESULTS

The Leidsestraat never experiences a density of traffic resulting in the overall slowing of pedestrian movement, although individual progress is impeded frequently and temporarily. The average peak of 4.6 persons/minute/m is below those levels found to result in reduced speed, platooning and reduced crossmovement, all of which can however be observed nearby on the Kalverstraat. The pedestrian density9 on the Leidsestraat is 0.18 pedestrians/m2. This is much less than the critical value of 1 for a reduction of speed.lo Nevertheless, it has been suggested that truly unimpeded walking requires about 12 m2/pedestrian, equivalent to 6.5 pedestrians/ minute/m of walkway width.7 The Leidsestraat average pedestrian density is 6.1 m2/pedestrian with a standard deviation of 2.1. If only effective walkway width is considered, i.e., the flat-bricked area, then the space/pedestrian would approach 4 m2. While the average walking speed is a relatively high 5.3 kilometers per hour (kph), slower-moving platoons and meandering tourists frustrate free movement several times while traversing a single block.