A permit system implemented for hikers heading to the summit of Half Dome in Yosemite National Park does not appear to be improving overall safety conditions, according to a report that analyzes this past summer's hiking numbers.
While the permit system for folks hoping to summit Half Dome on weekends and holidays did indeed tamp down those crowds, it also had the "unintended consequence" of moving the crowds to weekdays, when permits are not required, according to a review of hiker traffic.
In the end, the study concludes, "these results suggest that the objectives of visitor safety and acceptable experiential conditions on the cable route cannot be provided with a daily visitor use permit system implemented only on some, but not all, days of the week."
Half Dome long has attracted throngs of hikers -- some experienced, some not, some well-equipped for the task, some not -- and at times there have been accusations that the heavy, unregulated traffic to the top of the iconic dome has played a role in some accidents on the dome's steeply pitched shoulder.
Yosemite officials currently are working on a long-term management plan for the route to the top of Half Dome, but until that is in place they have instituted a permit system for Fridays, Saturdays, Sundays, and federal holidays whenever the cables are up. That system restricts to 400 the number of permits that can be issued for any one of those days.
This past summer the average number of hikers heading up Half Dome on weekends was right about 300 per day, a tally nearly 100 fewer than the average weekday traffic load of 416 hikers noted during the 2008 season, according to the Half Dome Trail Visitor Use Monitoring Report just released by the park.
Weekday use, however, witnessed a sizable increase, averaging 635 hikers per day, a rate approaching weekend traffic (about 692/day) on Half Dome in 2008 and much greater than the 2008 weekday average of 416 hikers per day, the report noted.
"Thus, it appears that an unintended consequence of the permit system was the interchange of use levels from weekend to weekdays," the authors wrote.
And those weekday numbers exposed many hikers to potentially dangerous crowding on the 400-foot cable-assisted route to the top of the dome, the very situation park officials hoped to alleviate on weekends, which historically saw the heaviest hiker traffic, with the permit system.
The monitoring report (attached below) noted that an "unimpeded visitor travel" threshold of just 30 people at any one time on the cables leading up the dome's shoulder was exceeded 15 percent on weekends under the permit system, but that on weekdays when permits were not required that limit was surpassed 65 percent of the time.
A higher "threshold," of 70 people on the cables at any one time, a number "when visitors perceive safety issues and unacceptable experiential conditions," was not exceeded on sampled weekend days, but was surpassed almost a quarter of the time on weekdays, the report added.
The busiest day on the way to the top of Half Dome appears to be Mondays, when an average 732 hikers headed up Half dome, the report notes. The slowest days were Sundays, when the average was just shy of 275 hikers.
Not surprisingly, in light of the increased number of hikers on non-permit days, those who either avoided the permits or couldn't get one spent more time on the cabled route to the summit than those who landed permits. On permit days those heading up the route, arguably the scariest and most dangerous part of the hike, spent 28 minutes working their way to the summit, while on non-permit days hikers spent nearly 41 minutes, on average, on the cables, the report points out.
And yet, those who spent the most time getting to the summit of Half Dome on average spent a shorter amount of time there (48 minutes, 235 seconds) than those with permits (52 minutes, 54 seconds) who reached the top more quickly.
The difference in traffic on permit days vs. non-permit days also had a tremendous effect on hikers traveling the roughly 3 miles of trail from Nevada Falls to Half Dome Junction. While permit days placed 68 hikers per hour on this segment, on non-permit days that number ballooned to 117 hikers per hour, according to the report.