If you find more permanent count sites are needed or desired, the next step is to determine where to put them and what technology to install.
Selecting sites deserves a book of its own, as there are many approaches and each jurisdiction will have its own priorities and values. Most agencies choose based on a multitude of criteria including
- Non-motorized traffic volume
- Facility type
- Level of urbanization
- Interest of local communityConvenience
- Appropriate location for counting technology
There is much to say about automated continuous bicycle and pedestrian counters. We won’t try to list all of the technologies here. The Traffic Monitoring Guide, Section 4.2, provides a good summary of the technologies available and offers a useful graphic to help choose an appropriate technology. This graphic is reproduced below for your convenience.
Just released in 2015, NCHRP 797 Guidebook on Pedestrian and Bicycle Volume Data Collection provides useful advice on bicycle and pedestrian counting equipment, validation and maintenance.
Also available is an online document detailing how the NCHRP project team's testing of counting equipment and analysis. http://onlinepubs.trb.org/onlinepubs/nchrp/nchrp_w205.pdf
Ryus, Paul, Erin Ferguson, Kelly M. Lausten, Robert J. Schneider, Frank R. Proulx, Tony Hull, and Luis Miranda-Moreno. NCHRP 797 Guidebook on Pedestrian and Bicycle Volume Data Collection. Washington, DC: NCHRP, 2015.
Ryus, Paul, Frank R. Proulx, Robert J. Schneider, Tony Hull, and Luis Miranda-Moreno. Methods and Technologies for Pedestrian and Bicycle Volume Data Collection. Washington, DC: National Cooperative Highway Research Program, 2015.
The Los Angeles metropolitan area hosts a Bike Count Data Clearinghouse and provides guidance on selecting sites and counting technologies as shown in this figure.
GUIDANCE FROM THE TRAFFIC MONITORING GUIDE 2013, SECTION 4.4.5
4.4.5 STEP 6: SELECT SPECIFIC COUNT LOCATIONS
Once the number of locations within factor groups has been established, the next step is to identify specific monitoring locations. Several considerations should be addressed in this step.
Differentiating pedestrian and bicyclist traffic - Will pedestrian and bicyclist traffic be separately monitored at each permanent count location? In the case of shared use paths, pedestrians and bicyclists will be traveling in the same space, and specialized equipment should be used to differentiate these different user types. In other situations, it may be preferable to monitor bicyclists separately from pedestrians. Exclusive bicycle lanes or separated bicycle paths can be instrumented with inductance loops (permanent) or pneumatic tubes (short-duration) that will not count larger/heavier motorized vehicles. Pedestrian malls, sidewalks or walkways can be instrumented with a single-purpose infrared counter if bicyclists are not typically present.
Selecting representative permanent count locations – Although it may be tempting to select the most heavily used locations for permanent monitoring, one should focus primarily on selecting those locations that are most representative of prevailing non-motorized traffic patterns (while still having moderate non-motorized traffic levels). In some cases, permanent count locations may be installed at low-use locations if higher use is expected after pedestrian or bicycle facility construction. The primary purpose of these continuous monitoring locations is to factor/annualize the other short-duration counts. Continuous counts at a high-pedestrian or high-bicyclist location may look impressive, but may not yield accurate results when factoring short-duration counts.
Selecting optimal installation locations – Once a general site location is identified, the optimal installation location should be chosen for the specific monitoring technology and equipment. In most cases, the optimal location is:
• On straight, level sections of road or trail, not on curves or on or near a steep grade;
• On smooth pavement or other compacted surface;
• Where the traveled way is clearly delineated and deviation is not common;
• For infrared sensors, not near water or in direct sunlight;
• For infrared sensors, not directly facing the roadway unless a vertical barrier exists; and
• For inductance loop detectors, not near high-power utility lines that could disrupt or distort the detection capability.