Traffic counters powered by artificial intelligence are providing a new window into the volume of vehicles using the McLain Flats-Power Plant Road alternate access to Aspen.
An analysis of a calendar year’s worth of data confirms that the side-entrance traffic makes up a significant portion of total traffic, as drivers seek to beat the gridlock that typically chokes Highway 82 during the morning and afternoon peak periods. Added together, vehicle counts from Highway 82 and Power Plant Road through all of 2025 show last year’s traffic approaching a 1993 threshold established as a benchmark to stay below.
Until last year, traffic entering and leaving Aspen’s West End via Power Plant Road and traveling on McLain Flats was not consistently monitored, with the only continuous traffic counter in Aspen located on Highway 82 between the Castle Creek Bridge and Cemetery Lane. But in late 2024 and early 2025, the Elected Officials Transportation Committee (EOTC), made up of representatives of the city of Aspen, Pitkin County and Snowmass Village, installed seven more counters, including on Power Plant Road, McLain Flats Road, Owl Creek Road and Maroon Creek Road, and replaced the existing counter near Castle Creek Bridge. This new network provides the most complete picture to date of the number of vehicles entering and leaving Aspen daily, as well as use patterns on commuting routes other than Highway 82. The cameras can also distinguish smaller passenger cars from larger work and delivery trucks.
Data obtained by Aspen Journalism from the new Castle Creek Bridge counter and the Power Plant Road counter show that the annual average daily traffic (AADT) entering and leaving Aspen reached 22,449 in 2025, including a daily average of 1,657 vehicles for Power Plant Road. That put the combined Castle Creek Bridge and Power Plant Road traffic about 5% below 1993’s AADT of 23,695, a threshold that local officials want to keep traffic levels under. (The 1993 count only includes traffic on the Castle Creek Bridge.)
2025’s combined entrance-traffic figure is also on par with the Colorado Department of Transportation (CDOT) counter on Highway 82 in Old Snowmass that recorded an AADT of 22,711 vehicles in 2025, providing further insight into the relatively low number of vehicles that use the Brush Creek Park and Ride to catch a bus for the last leg of their commute to Aspen.
Aspen Journalism’s analysis shows that the total number of vehicles using Power Plant Road over the course of an entire day is about 7% of the total traffic entering and leaving Aspen. During peak periods, however, the proportion of traffic using the alternate access spikes, with up to 34% of afternoon peak traffic exiting town via Power Plant Road to bypass the Highway 82 S-curves, according to a 2024 analysis by city of Aspen contractor Jacobs Engineering. Hour-by-hour data from the EOTC’s new traffic counters was not available in time for this story’s publication.
Using only Castle Creek Bridge counts, 2025’s AADT of 20,791 recorded by the new camera was about 3.5% up from 20,072 in 2024 captured by the old bridge counter.
The summer season was the busiest, with July and August recording the highest average daily traffic, with 28,807 in July and 26,464 in August. And July was one of two months in 2025 exceeding a 1993 monthly count — July 1993 saw an AADT of 28,600, while February 2025 paced slightly above February 1993’s monthly average of 24,300. The busiest day of 2025 was Friday, Aug. 8, when a total of 32,787 vehicles entered and left Aspen, including 28,359 using Castle Creek Bridge and 4,428 vehicles — 14% of the total — through Power Plant Road. McLain Flats counted 5,488 vehicles on that day.
Representatives of the Transportation Coalition for the 21st Century, which was established last year to develop strategies to mitigate traffic congestion in the Roaring Fork Valley, agreed that even though last year’s numbers didn’t exceed 1993, traffic may feel worse due to the “broadening of the curve.“
“It used to be a very distinct peak-hour curve. Now, it’s like peak hour morning and afternoon has broadened,” said coalition co-founder and former Aspen Mayor John Bennett.
Coalition co-chair Susan Marolt added that there’s more traffic today than in 1993 that goes out to Cemetery Lane, Castle Creek or Maroon Creek — for example, a major expansion of Aspen Highlands’ base village was completed in 2001. “We also have increased transit ridership now, and so that’s great, but it also means that there’s that many more people that are coming into Aspen,” she said.
In December, Aspen City Council signed $397,000 in contracts for the study and design of new signage that could mitigate or change traffic flows in the West End, including new school zone signage, additional pedestrian area and weight restrictions on Power Plant Road.
“This is the first time we’re really paying any real attention to this neighborhood, in a neighborhood that is dealing with all the impacts of a failed entrance where we know that 34% of the traffic coming into Aspen throughout the whole day leaves at the end of the day through the West End, Power Plant Road because past councils blocked off Bleeker Street and other streets,” Aspen Mayor Rachel Richards said at the Dec. 2 City Council meeting.
McLain Flats and Smith Hill
McLain Flats Road saw an average of 2,408 vehicles a day in 2025, topping at 5,783 on June 12, according to its new counter. Pitkin County Engineer Andrew Knapp said he wasn’t surprised by these numbers and provided a few historical data points collected by the county showing that the daily average in January 2021 was 2,132 and reached 5,120 in July 2022.
These significant traffic volumes help inform the need for safety enhancements planned for next year that will see changes to the intersection of Highway 82 and Smith Hill Way near Woody Creek, which is the main access for drivers to or from McLain Flats.
Last year, CDOT granted $2.6 million in federal and state funds to Pitkin County to make safety improvements at that intersection and another crash-prone intersection at Lazy Glen. The work at Smith Hill Way will create the first so-called “Michigan left” configuration in Colorado and is expected to reduce crashes by 35%.
“CDOT and county engineers observed that drivers attempting left turns [from Smith Hill onto Highway 82] often misjudge the speed or gap of oncoming traffic, leading to severe T-bone crashes — including one fatal crash in 2018,” according to a Pitkin County news release.
The project will convert the intersection into what is technically known as a “modified reduced conflict U-turn configuration,” more commonly known as a “Michigan left.” Drivers heading upvalley from Smith Hill will make a right turn into the downvalley lane of Highway 82, followed by a U-turn at a new median crossover, instead of a direct left turn into cross-traffic.
Morning upvalley traffic turning left off the highway onto Smith Hill in order to reach McLain Flats often backs up along the left shoulder of the highway and through the existing median crossover, making the intersection even more dangerous for vehicles turning left from Smith Hill onto Highway 82. Under the “Michigan left” configuration, drivers will need to proceed beyond the existing intersection to a new median crossover location to make a U-turn, followed by a right turn onto Smith Hill in order to reach McLain Flats.
“I think the new configuration will lead to a minor reduction in use of McLain Flats as the access into Aspen due to the additional out-of-direction travel that will be required, but I don’t expect a large reduction in traffic,” Knapp said. Construction is expected to take place from May 2027 through October 2027.
RFTA and Brush Creek
Last year’s Roaring Fork Transportation Authority (RFTA) ridership was up 0.8% to 5.074 million in 2025 from 5.032 million in 2024. The L (“local”) bus route serving the Highway 82 corridor dropped to 918,000 in 2025 from 940,000 in 2024, while VelociRFTA (BRT) ridership along the highway increased slightly to 1.136 million from 1.109 million.
In 2025, 16% of RFTA BRT and L riders going upvalley boarded at the Brush Creek Park and Ride, which is a parking-and-transit hub along Highway 82 at Brush Creek Road. A total of 285,000 rides in 2025 either started at Brush Creek Park & Ride heading upvalley or ended at the Intercept lot going downvalley. This represents 781 rides a day starting or ending at Brush Creek, or about 3.5% of total daily traffic recorded in Old Snowmass last year.
According to the EOTC’s Brush Creek Park & Ride Monitoring and Management Plan published in October using the city of Aspen’s counts of 245 days in 2024, the 400-space parking lot was between 45% full during the spring offseasons to 88% full on the day after Thanksgiving between noon and 1 p.m. The lot averaged 268 parked vehicles by midday throughout the year. “The early afternoon period sees the highest parking utilization throughout the day on typical days,” according to the report.
Overflow lots located north and south of the paved parking area are made available during special events, such as JAS Experience or the X Games, which can increase the parking capacity by approximately 400 spaces, providing a total of over 800 spaces.
Bus fares from Brush Creek into Aspen and Snowmass Village are free, while trips to the upper valley from points below Brush Creek cost between $3 and $8 each way.
“We have a free parking lot with free WiFi and free fares to [resort] destinations, and yet … as something that commuters take everyday, we’re still not full.” Pitkin County Commissioner Jeffrey Woodruff said at an EOTC retreat April 23. “Even with free transportation, we cannot fill up, and so to me, I’m happy to look at another PDF and plan, but I’d rather see why isn’t this lot full every step of the way.” Woodruff suggested starting free fares at a lower point in the valley, such as in Basalt, to take people off the road before Snowmass Canyon.
While the EOTC board members were discussing trip-reductions ideas, including how to increase the use of the Brush Creek Park & Ride, Pitkin County Commissioner Francie Jacober shared her concerns at the retreat about encouraging people to use the park and ride.
“I want us to think about the effects of these commuters who come to Aspen on the people who live in Glenwood Springs because their traffic is just as bad, if not worse, than the upper valley traffic … A lot of it is people coming to Aspen,” Jacober said. “If people get in their car and drive to Brush Creek and then get on the bus to avoid traffic in Aspen or parking fees in Aspen, that doesn’t help downvalley traffic. To me, that’s not a solution that helps the whole valley; it helps Aspen.” Jacober suggested that free fares for bus trips systemwide should be considered.
The average daily traffic on the Grand Avenue portion of Highway 82 in Glenwood Springs recorded by the CDOT counter located at the Blake Avenue intersection near Walmart reached a record high in 2025, with about 27,700 vehicles daily, over 1,000 more a day than in 2024.
Interstate 70 traffic passing the Glenwood exit reached about 19,700 last year, the second highest on record, after 2024’s 20,000 daily traffic count, with around 25,200 vehicles daily near Silt — the highest on record, but 9% below Glenwood Springs’s AADT.
“We have more volume on Highway 82, in some cases on a two-lane facility, that we’re trying to accommodate than on I-70,” RFTA CEO Kurt Ravenschlag said at the RFTA board meeting April 9.
