StrataGist
Local Perspectives On National Trends (Southern Oregon)
As Feed-back.com's researchers hit the road for vacation in August and September, we wanted to see what kinds of vehicles people were driving along I-5. Tallies tracked the following general categories: Campers / coaches, recreational vehicles / rentals, and trailers. Some interesting findings are presented below.
Northern California & Southern Oregon Vehicle Counts On I-5
Introduction:
Interstate 5 (I-5) is a West Coast corridor that extends through California, Oregon, and Washington between the U.S. borders with Mexico and Canada. According to the latest I-5 statistics from Department Of Transportation (DOT) Fact Sheet,"… the average daily traffic throughout the entire corridor is approximately 71,000 with a maximum over 300,000." The range for average daily truck traffic is nearly 10,000 with a maximum over 35,000. Urban areas account for 40% of I-5, nearly two-thirds of which (65%) are heavily congested.
The Interstate 5 Transportation Concept Report (February 2008) evaluates current traffic and forecasts future needs from Sacramento to the Oregon border. Two useful parameters are used to estimate vehicle volumes. Annual Average Daily Traffic (AADT) is generated by dividing total traffic volume for the year by 365 days. AADT data for 2005 from Corning to the Oregon border ranged from a low of 14,400 (an average of 10 vehicles per minute in mountainous Siskiyou County) to a high of 67,000 (an average of 47 vehicles per minute in Redding CA).
Level Of Service (LOS) qualitatively describes conditions within a traffic stream and density, using categories that range from A (0 to 11 passenger cars per mile per lane / "free flowing with low volumes and high speeds") to E (>45 passenger cars per mile per lane / "speeds are reduced", periods of "stop and go", "downstream congestion", etc.).
I-5 Trip Descriptions:
The first early August rural area round trip travelled approximately 60 miles of I-5 between Ashland (Oregon) and Mt. Shasta (California). The mid-August round trip covered approximately 200 miles from Medford (Oregon) through one "urban" area (Redding CA) to Corning (California). The third trip during the first week of September included approximately 100 miles of Southern Oregon from north Medford through one "urban" area (Roseburg) to Curtin.
Occasional spot checks were made to estimate vehicles-per-mile (VPM), which ranged from a low of 18 to a high of 30. For all three I-5 trips, VPM figures were comparable to the I-5 Concept Report's two lowest LOS categories (A and B) and far below DOT averages (which include urban areas).
Vehicle Counts:
The three-day trip from Ashland to Mt. Shasta and back began Thursday evening, August 7th and concluded early Saturday afternoon, August 9th, 2008. Northbound vehicles were counted on the first day. Southbound vehicles were counted on the return trip, which were twice as numerous. Similarly, there were more recreational vehicles (1.0% versus 0.6%) and trailers (1.4% versus 0.6%) on the return trip.
The eight-day round trip from Medford to Corning began late Monday afternoon, August 11th and ended the evening of Monday, August 18th, 2008. Traffic densities were comparable on both legs of the trip. Northbound traffic was evaluated on the first day. Southbound coaches/motor homes, campers, and other recreational vehicles accounted for much higher portions of total traffic on the return trip (3.5% versus 1.0%). A nearly three-fold increase was seen for vehicles with luggage racks and/or trailers.
Truck counts were included in a third trip from Medford (Oregon) to Curtin (Oregon), which began early Friday morning, September 5th and ended mid-day, Sunday, September 7th, 2008. Based on periodic spot checks, traffic was moderate on the first day (22 - 24 VPM) and heavier on the return trip (23 - 36 VPM) with averages of 23 VPM and 28 VPM, respectively. On the return trip, there were more coaches / campers (3.2% versus 1.9%), recreational vehicles (1.6% versus 1.1%), and trailers (3.7% versus 2.0%). On the first day, trucks accounted for 13.7% of traffic, compared with 20.1% on the return trip.
Patterns & Trends:
As might be expected, Feed-back.com's findings suggest that weekend traffic on I-5 includes a larger portion of coaches / campers, recreational vehicles, and trailers than during the week. Recreational vehicles and trailers (0.6% to 4%) were more abundant than coaches and campers (0.3% to 1.8%).
According to facts and figures from Travel Oregon's 2007 - 2009 Assessment Report, leisure accounted for 75% of U.S. domestic travel in 2005 (Travel Industry Association of America). Most leisure trips (88%) are made by car, recreational vehicle, or truck. More than 75% of Americans participate in "active outdoor recreation" each year. Camping, hiking, and biking are the three most popular outdoor vacation activities.
During the Southern Oregon I-5 trip, truck traffic on the weekday was comparable to a 14% estimate derived from DOT statistics. Weekend volume was much higher (20.1%).For past issues of StrataGist, visit the Archive.
