Volunteers helped the City of Salem complete its first ever bicycle count this summer. During the summer months 21 volunteers performed 40 manual counts at 32 sites around the city. Counters tallied direction, gender, and helmet use during two-hour peak traffic times, either 7am to 9am, or 4pm to 6pm. The two-hour counts were normalized to 24-hour volumes. City staff then mapped the count data.
By comparison, the Portland Office of Transportation has been conducting counts annually since 1992. At the same time this year, volunteers and city Transportation staff in Portland performed 115 counts. Their counts show clear year-over-year trends of increasing bicycle use. Here's the Portland report. (It's big!)
Drawing conclusions from Salem’s count data is more difficult without the trend lines to smooth out random variation. For example, the sunny day traffic was approximately double cloudy day traffic (moreover, a couple of March counts were half the corresponding summer counts). Even so, since Salem participation in the Bicycle Transportation Alliance Bike Commute Challenge indexes closely to Portland’s over the last five years, it is reasonable to hope that Salem trends will follow Portland trends. On this assumption, helmet usage and the gender ratios suggest Salem may be ten to fifteen years behind Portland in bicycle usage.
Not surprisingly, bicycle usage is greatest in the older parts of the city – the core downtown area where large employers are located, where there are fewer hills, and where the older street grid makes it possible for bicyclists to avoid arterial roads.
High and Low Individual Counts
- 585 at 12th & Chemeketa (ave at this location - 415)
- Zero at Fairview & Summer
Counts by Segment
- over 300 bicyclists – 3 sites – all on Chemeketa
- between 200 and 300 – 5 sites
- between 100 and 200 – 13 sites
- under 100 – 11 sites
Highest use on Residential Local or Collector Streets
Most arterial streets did not show the highest bicycle usage. Where counts were high on arterials, bicyclists crossing the arterial rather than traveling along the arterial seemed to account for most of the traffic. This should be investigated more closely next year.
- Chemeketa – between 14th & 17th, bicycle traffic is 30% or more of total vehicular traffic
- D street
Helmet use increases as bicyclists increase. In both Portland and Salem women use helmets at significantly higher rates than men.
2008 Helmet use rates:
- In Salem 55% of riders used helmets.
- In Portland 80% of riders used helmets.
When bicycling is safe and convenient, women and families bicycle in large numbers. While bicycle usage is being established more men bicycle. Over time as bicycling becomes more prevalent, gender ratios move towards a 50/50 split.
- In Portland in 1992 the split was about 80/20 males-to-females.
- In Portland 1999 it was 75/25.
- In Salem in 2008 it was also 75/25.
- In Portland in 2008 it was 68/32.
- In Denmark, Germany, and the Netherlands, the Gender split is about 50/50.
For Next Year
The first count was a terrific success and created a good baseline for further comparisons. We hope to evaluate year-over-year growth at many of the same sites. The data also raises addition questions and opportunities for evaluation next year:
- Focus counts on arterials and parallel residential streets (such as high vs. commercial) to determine bicyclist preference.
- Evaluate the bridges – the new Union RR bridge and the existing Center St. multi-use path.
- Assess bicycle traffic to Schools, especially Chemeketa, Willamette, and area high schools.
- Perform more counts outside of the central city – North Salem & Keizer; East Salem, especially around Lancaster; South Salem in the hills and on the arterial/collector network; and in West Salem.
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