The Sedona Shuttle website describes the trailhead shuttles as “eco-friendly” and claims that the shuttles eliminated 286 metric tons of CO2 equivalent emissions during their first year of operation.
The 2022 Transportation Energy Data Book compiled by Oak Ridge National Laboratory showed that motorcycles were the most energy-efficient form of on-road transportation, consuming 2,370 BTUs per passenger-mile. Cars came in at 2,787 BTUs per passenger-mile and personal trucks at 3,212 BTUs. Buses use 4,634 BTUs per passenger mile — 66% more than passenger cars.
The least efficient form of onroad transportation was demand-response services — similar to Sedona’s proposed microtransit service — which averaged energy consumption of 15,527 BTUs per passenger-mile.
If buses, on average, consume 1,847 BTUs more per passenger-mile than cars, then for about 142,000 passengers, the trailhead shuttles released 21 tons of CO2 e more than cars would have done.
However, the city of Sedona bought hybrid buses, which, city transit administrator Robert Weber stated in August 2021, are more efficient than all-gas buses and can achieve up to 13 miles per gallon.
Route 11 covers 168 miles per day, Route 12 covers 125 miles, Route 14 covers 34 miles and Route 15 covers 224 miles, for a total of 551 miles per day and 122,322 miles per year. This works out, at the most favorable estimate for fuel efficiency, to 91 tons of total annual emissions.
The EPA estimates that the average fuel economy for passenger cars is 24.2 miles per gallon. Cars covering the same distance would have emitted 49 tons of CO2 e, which is 42 tons, or 46%, less than the trailhead shuttles did.
For the trailhead shuttles to have reduced emissions by the amount the city has claimed, they would have had to have prevented more than 787,000 miles of driving by passenger cars.
Other city officials have also explained that the shuttles were intended to reduce complaints from residents of a few neighborhoods in particular — Cathedral Rock, Soldiers Pass, Dry Creek, Mescal and Little Horse — and to reduce damage to what they described as the “fragile environment” rather than to improve traffic or make it easier for locals to get around town.
“They weren’t deployed, really, to help traffic,” Weber told the city council regarding the trailhead shuttles on Oct. 12. “They were deployed at the request of the citizens … to deal with these public safety issues and return some of these neighborhoods to some semblance of normalcy, and I think they did that, and that’s what they were designed to do.”
“Residents in neighborhoods where popular trailheads are located were being overrun with traffic as more and more people tried to access the trails,” City Manager Karen Osburn said.
City communications manager Lauren Brown stated in April that the city’s return on its investment in the trailhead shuttles “comes from all the residents telling us they appreciate our work to restore their neighborhood, [and] from the over 283,000 passenger boardings we saw in a year.”
The shuttle website also features comments from residents of the Soldier Pass and Back o’ Beyond areas talking about their neighborhoods since the city eliminated street parking, compelling hikers to walk or use the shuttles.
The cost so far has been $2,207,706.
The city’s proposed 2024 budget calls for another $4,745,880 to be spent on reducing congestion in these neighborhoods.
