2016 TRAIL COUNTER DATA REPORT REPORT SUMMARY In order to better understand trail use levels and trends, the Tahoe Rim Trail Association has utilized passive infrared and magnetic trail counters on various places within the Tahoe Rim Trail system. In 2016, 25 counters were deployed, and the data collected have been analyzed. In general, the counters have confirmed anecdotal evidence and suggest that High Use areas of the system receive over 116 average daily trips in the peak use season. Trends indicate that use on the Tahoe Rim Trail is increasing rapidly and is up about 45% over the past eight or nine years. The total number of trail users in 2016 is estimated at over 400,000. Although the data does have limitations, the conclusions reached in this report represent a good faith effort to evaluate trail use on the Tahoe Rim Trail system. Using the results reported here, and by collecting additional data in the future, the Tahoe Rim Trail Association and its partners can have defensible data upon which to make management decisions. TABLE OF CONTENTS PROGRAM OVERVIEW 1 PROGRAM DESCRIPTION 01 PROGRAM GOALS 2016 COUNTER S LIMITATIONS INFRARED COUNTERS 5 02 ANALYSIS TECHNIQUES IR COUNTER RESULTS BICYCLE COUNTERS 15 03 ANALYSIS TECHNIQUES MB COUNTER RESULTS NEXT STEPS 19 04 LESSONS LEARNED RECOMMENDATIONS FOR 2017 & BEYOND PROGRAM OVERVIEW PROGRAM DESCRIPTION Both anecdotal and scientific observations have concluded that recreation use in the Tahoe Basin is on the rise and is currently 01 at historically high levels. Visitation to the Basin is at around 5.7 million annually, and among those visitors recreation in the form of hiking and mountain biking is more popular than ever before. As one of the premier outdoor recreation resources in the Basin, the 197-mile Tahoe Rim Trail (TRT) system is seeing more users than ever before. Understanding use levels and trends on the trail is essential for adjusting management strategies to meet evolving challenges. Beginning in 2007, the Tahoe Rim Trail Association (TRTA) has used trail counters to monitor use levels. The first few years of monitoring were spotty, without enough counters to cover much of the trail. However, with the recent acquisition of additional hardware, the organization now owns approximately 20 infrared (IR) trail counters and 6 magnetic bicycle (MB) counters. The IR counters collect information on all trail users while the MB counters collect information only on wheeled traffic. Both counter types collect data in the form of individual trips or hits: each time someone passes the counter a single trip or hit is recorded. Counters allow for close monitoring of multiple sites around the trail at any given time and can potentially provide data for informing critical management decisions. The data gathered through this program is of particular use for identifying and managing high-use areas where additional resources may be warranted to reduce environmental risks, repair or prevent tread deficiencies, or mitigate natural resource damage. In addition, the data is essential for establishing baseline use numbers before connector trails are built and for assessing the increased traffic from those trails. Further, the counters are a powerful tool in monitoring illegal trail use, such as mountain bike incursions into Designated Wilderness Areas. The data resulting from this program can also be used to more accurately assess the overall number of trail users on the TRT and to create stronger arguments regarding relevancy when competing for funding, marketing the trail, or any time the significance of the trail may be called into question. PROGRAM GOALS The goals of this program are to: 1) Develop a digital database that stores information collected from the counters, and 2) Analyze and share the data with partners so that it can be used to inform management decisions, fundraising, and other programs. Specifically, this report seeks to analyze collected data to answer the following key questions: 1) Which areas of the trail receive High, Moderate, and Low use? 2) What are the trends in trail use in general and on different segments? 1 3) How many trail users recreated on the Tahoe Rim Trail system in 2016? 4) What is the compliance rate for the Even/Odd restricted access advisory trail section? 5) How many mountain bikes trespass into the Mount Rose Wilderness from the TRT? and 6) What is the rate of mountain bike incursion on the restricted-access section from Hobart Road south to Spooner Summit? The digital databases that store and analyze the data recorded by the trail counters are maintained both through a Geographical Information System (GIS) and online via the TRAFx Datanet website. This report was developed to share the knowledge gained through the trail counter program throughout the TRTA and amongst partners. 2016 COUNTERS In 2016, 19 IR and 6 MB counters were installed in the field (see Map 1 and Map 2 for exact locations). Though it varied by counter, on average the devices collected data for between three and four months from mid-June to mid- October. While all of the MB counters functioned properly for the duration of the season, three of the IR counters partially failed and three failed completely. The three IR counters that partially failed were Spooner North, Brockway East, and Brockway West 2. The counter at Spooner North took incorrect readings from the time of its installation until the month of September for unknown reasons. The malfunction may have been due to interference from natural elements such as a leaf blocking the counter. The Brockway East counter collected good data from late June until the end of July when it was tampered with by trail users. The Brockway West 2 counter collected data from July through early August when it stopped collecting. It was found suffering from water damage. The three IR counters that failed completely were the Van Sickle Connector, Ward Creek, and Stagecoach North. The Van Sickle Connector counter was vandalized by trail users and has not been recovered. The Ward Creek counter failed because a chunk of bark either fell or was placed in front of it. The Stagecoach North counter failed due to an internal technical error. LIMITATIONS The data and conclusions presented in this report are a result of a good faith effort to accurately portray trail use on the TRT system based on limited information. Both passive infrared and magnetic counters have known issues in collected accurate numbers of users when they travel in groups and therefore tend to undercount. Due to weather and logistical constraints, counters traditionally spend only a small portion of the year on the trail, and unfortunately the dates have varied widely from year to year and counter to counter. This makes it impossible to account for known issues that affect use levels, such as the shift northbound PCT hikers make to travel later in the season when summer snow levels remain high. While attempts have been to normalize data the only way to overcome these limitations is to amass a robust data set that spans long periods of the year over multiple years. 2 2016 INFRARED TRAIL MOUNT ROSE COUNTER LOCATIONS WILDERNESS MAP 1 TAHOE NATIONAL FOREST GRANITE CHIEF WILDERNESS NEVADA CALIFORNIA ELDORADO NATIONAL FOREST DESOLATION WILDERNESS LEGEND Tahoe Rim Trail System LAKE TAHOE National Forest BASIN HUMBOLDT- MANAGEMENT TOIYABE UNIT NATIONAL Designated FOREST Wilderness Lake Tahoe NV State Park Successful Counters Partially Failed Counters Failed Counters 0 3 6 Miles ¸ 3 2016 MOUNTAIN BIKE MOUNT ROSE COUNTER LOCATIONS WILDERNESS MAP 2 TAHOE NATIONAL FOREST GRANITE CHIEF WILDERNESS NEVADA CALIFORNIA ELDORADO NATIONAL FOREST DESOLATION WILDERNESS LEGEND LAKE TAHOE BASIN HUMBOLDT- Tahoe Rim Trail MANAGEMENT TOIYABE System UNIT NATIONAL FOREST National Forest Designated Wilderness Lake Tahoe NV State Park Mountain Bike Counters 0 3 6 Miles ¸ 4 INFRARED COUNTERS ANALYSIS TECHNIQUES 02 Trail Use Levels In order to answer the question, “Which areas of the trail receive High, Moderate, and Low use?” data on average daily trips (ADT) from the IR counters were utilized. Not all counters collected data during the same time periods, so data from July 1 through September 30 (92 days) was used as a common timeframe. This period was used because it encompasses the snow-free season with the most comfortable temperatures during which most trail use occurs and because most IR counters in 2016 were active during that time. The IR counters that were not active for that entire period are the three that partially failed and the counter at Tahoe City North which only collected data for a short time frame (less than 6 weeks). In order to normalize data that was collected from those four counters, a correction equation was applied to all partial data sets to estimate ADT over the standard of 92 days. To do this, the average percent change in ADT for all units was calculated for the timeframe in which data was collected for any given unit with only partial data. The ADT for the timeframe in which a unit functioned was then multiplied by the average percent difference of all other units. For example, the Tahoe City North unit only collected data from July 27 to September 5. The ADT for that unit in that timeframe was 24.9. The average ADT for the functioning units in that same time period was 104.5. That figure is 97.4% of the ADT for the functioning units over the entire 92 day period (which is 101.8). 97.4% of 24.9 is 24.3, which is the corrected ADT for Tahoe City North. Note: Barker North was excluded from the calculations for correcting Brockway South #2 and Brockway North because it had a such a small sample size of overlapping days (nine and one, respectively).