BOULDER, Colo. (BRAIN) — Boulder County, Colo., has tweeked its vehicle traffic counters — the black tubes across traffic lanes seen across the country — to make them better able to distinguish bicycle traffic from other vehicles. The modified system, which county officials are presenting to colleagues nationally, helps the county get more affordable and more accurate figures; the data is used in part to measure how modified bike facilities on shared roads affect bike traffic levels.
Counters used exclusively to measure bike traffic, such as on a bike path, can be quite accurate, the county said. But some counters used to measure both motorized vehicles and bikes were only 62 percent accurate on average, at determining bike counts. In testing, the county found standard systems were especially bad at counting groups of bicyclists — a common sight on Boulder County roads.
So the county modified both the hardware and software settings of its Metrocount vehicle counters. On the physical side, the modified pneumatic counting tubes have thinner rubber walls and are anchored to the road with vinyl-covered sleeves to protect them from pinching at their attachment.
On the software side, Boulder County modified the Metrocount system's vehicle classification scheme to distinguish between trucks and bikes. In testing, the county found that the original system often mis-identified groups of cyclists as multi-axle trucks. The solution was to create new classes of vehicles in the system consisting of multiples of bikes.
The county also modified the software to better distinguish long-wheelbase bicycles from motorcycles. Bikes are now defined as having a wheelbase of 2.9 to 4 feet, while motorcycles have wheelbases of 4 feet to 5.6 feet. The software also was tweeked to better identify bikes that were drafting or riding side-by-side.
The county recently published an article about its new system in the Institute of Transportation Engineers Journal, and county employees have made presentations about it at several conferences.
The county also has recently published weekday and weekend traffic counts for various roads around the county and will resume counting next month.