This page delivers traffic analytics for Sully County, South Dakota. Our metrics are calculated with multi-sourced, cross-verified data from real-world mobile and sensor networks, and averaged for Sully County, South Dakota among 71 road miles divided in 174 segments. Our metrics go beyond simple volume counts to provide actionable insights on traffic intensity, congestion, commercial vehicle flow, and network performance with highest possible granularity (average segment length is 2,164 ft). Whether you are evaluating a new retail location, planning logistics routes, or assessing infrastructure needs, this data helps you move from assumptions to certainty.
Data sourced from TrafficZoom's proprietary analytics platform.
The average number of vehicles that travel each day over any road in the road network.
697
Trucks
Trucks
The percentage of the total traffic volume composed of heavy vehicles.
13.4%
Average travel time
Average travel time
The average time of travel averaged among all vehicles traveling on the road network.
35.8 min
Drivers’ average age
Drivers’ average age
Average age of residents in the geographic areas where the vehicle trips originated.
53.3 yrs
Drivers’ average income
Drivers’ average income
Average income of residents in the geographic areas where the vehicle trips originated.
$73,113
Our data indicates an estimated average traffic volume of 697 vehicles per day in Sully County, South Dakota that results in 50,791 vehicle-miles traveled per day (≈18.5 million per year). The traffic stream is comprised of an average of 1 truck for every 7 vehicles. Typical time spent behind the wheel per trip is 35.8 minutes, which already accounts for delays at signals, intersections, and congestion.
Analytical insight
When compared to the South Dakota state averages: At 697 vehicles per day, the average monitored road in Sully carries 78% less traffic than the state average of 3,156 vehicles per day - a critical factor for logistics and site planning. Network-wide, Sully accounts for about 0.2% of South Dakota's statewide total, at 50,791 vehicle-miles traveled per day (≈18.5 million per year). Journey times run 10% higher than the state level, at 35.8 minutes on average. Sully carries more traffic than 18% of counties in South Dakota. Its average travel time of 35.8 minutes is longer than 48% of counties in South Dakota.
Highway vs. Non-Highway Traffic Analysis
Highway Traffic
Traffic
Traffic
The average number of vehicles that travel each day over any road in the road network.
1,536
Trucks
Trucks
The percentage of the total traffic volume composed of heavy vehicles.
14.9%
Average travel time
Average travel time
The average time of travel averaged among all vehicles traveling on the road network.
49.7 min
Drivers’ average age
Drivers’ average age
Average age of residents in the geographic areas where the vehicle trips originated.
53.0 yrs
Drivers’ average income
Drivers’ average income
Average income of residents in the geographic areas where the vehicle trips originated.
$72,232
A significant volume of traffic in Sully County, South Dakota utilizes the highway network. The average highway carries 1,536 vehicles per day, 289% more than the average non-highway road in the same area, which carries 395 vehicles per day. That average covers 26 highway road miles divided in 46 segments (average segment length 2,937 ft), together carrying 38,689 vehicle-miles traveled per day (≈14.1 million per year). Trucks constitute 14.9% of highway traffic.
Analytical insight
The concentration of trucks on highways (14.9%) is 9% higher than the state average for similar road classifications. This indicates Sully serves as a significant freight corridor. For logistics operators, this validates the importance of highway access. 58% of counties in South Dakota see a lower highway truck share than Sully's 14.9%. 25% of counties in South Dakota see fewer highway trucks per day than Sully's roughly 228.
Non-highway traffic
Traffic
Traffic
The average number of vehicles that travel each day over any road in the road network.
395
Trucks
Trucks
The percentage of the total traffic volume composed of heavy vehicles.
8.8%
Average travel time
Average travel time
The average time of travel averaged among all vehicles traveling on the road network.
30.8 min
Drivers’ average age
Drivers’ average age
Average age of residents in the geographic areas where the vehicle trips originated.
54.3 yrs
Drivers’ average income
Drivers’ average income
Average income of residents in the geographic areas where the vehicle trips originated.
$74,383
The non-highway road network in Sully County, South Dakota supports a substantial volume of traffic. The average non-highway road carries 395 vehicles per day, 74% less than the average highway in the same area, which carries 1,536 vehicles per day. That average covers 46 non-highway road miles divided in 128 segments (average segment length 1,886 ft), together carrying 12,101 vehicle-miles traveled per day (≈4.4 million per year). Trucks constitute 8.8% of non-highway traffic.
Analytical insight
Compared to highways, non-highway routes see 40% fewer trucks by share. 48% of counties in South Dakota see shorter overall travel times than Sully. 57% of counties in South Dakota see lower average driver income among trip origins than Sully. Sully's median driver age is higher than 78% of counties in South Dakota.
Time-of-Day & Seasonal Patterns
Peak Traffic Windows
Weekday peaks:
AM peak 8:00 AM–12:00 PM and PM peak 12:00 PM–2:00 PM, with volumes reaching approximately 59% higher than the daily average.
Weekend traffic:
Weekend volumes run about 25% below weekday levels.
Seasonal Fluctuation
Busy season:
June–August is the high season, with volumes +16% versus the annual average.
Lowest month:
March is the quietest month, with volumes -22% versus the annual average.
Analytical insight
In Sully County, South Dakota, the peak hour concentrates about 7% of the day's traffic, and seasonal swing is pronounced at +16% in high season.
Traffic Flow Profile Comparison
Metric
Sully
South Dakota
Average
Difference
Traffic
697
3,156
-77.9%
Truck % (Total Traffic)
13.4%
10.3%
+30.7%
Truck % (Highway)
14.9%
13.6%
+9.5%
Avg. Travel Time
35.8 min
32.5 min
+10.4%
Frequently Asked Questions
The average daily traffic volume is calculated at 697 vehicles per day, providing a baseline for daily operations and site assessment.
The driver population in Sully skews older than 78% of counties in South Dakota.
Drivers on Sully roads have a median age of 53 years, and the median household income of the neighborhoods trips originate from averages $73,113 - useful context for retail siting and customer profiling.
Traffic volumes are typically 16% higher during June–August. Volumes drop to their lowest levels in March, averaging 545 vehicles per day - a 22% decrease from the annual average.
Trucks account for approximately 13.4% of the total traffic mix across all road types, with a significantly higher concentration of 14.9% on highways.
Approximately 50% of highway traffic and 10% of non-highway traffic consists of vehicles whose trip originates outside Sully County, South Dakota. This indicates that a portion of highway traffic is regional pass-through, while local roads are more representative of resident and commuter activity.
Weekday peaks occur between 8:00 AM and 12:00 PM in the morning and between 12:00 PM and 2:00 PM in the evening - about 59% above the daily average.
Data Sources & Methodology
The data presented on this page is derived from TrafficZoom's proprietary analytics platform, which aggregates and normalizes information from multiple sources, including:
Mobile device location data (anonymized and aggregated)
