No one said figuring out mountain skiing capacity would be easy. But by using an established model currently in use by ski area designers and consultants, it is possible to get real-world estimates. With any luck, this article will bring a little understanding to the subject of developing a firm mountain capacity figure because with expansion costs reaching into the millions these days, the ultimate goal should be to make well-informed decisions by way of planning.
With that in mind, we’ve put together a model that can be used to project the outcome of a number of different options available to ski area managers and owners. When working with such a model, however, it is important to note that the model is only a technique to help find answers. It is not an answer in and of itself. But it can, for example, give management the ability to compare the impact of a new detachable with that of an existing fixed-grip. The comparison can reveal capacity projections showing that moving the existing lift to underserved terrain could be more useful than buying new. It might also, however, point out that the new quad will result in a net increase in system capacity. The model can also be used to show the effects of increasing trail acreage served by an existing lift. The result can be a valuable piece of information that tells how many skiers and snowboarders can incrementally be accommodated at the ski area under “what-if” conditions. Again, it might reveal that the resort is underutilizing capacity, providing the impetus for renewed marketing plans.
We’ve set up an interactive table on SAM’s Website at www.saminfo.com allowing ski areas to determine capacity as set forth in this article . It provides a Skiers At One Time (SAOT) figure, one of three models currently used in mountain planning to estimate capacity. They all use similar formulas to get similar results. Here, we’ve attempted to simplify the use of the model and explain the logic behind its calculations.
SAOT uses the pod concept that considers people standing in the maze, riding on the lift and skiing (and snowboarding) down the network of trails that feed back to the loading area for the lift in question.
When thinking of a pod’s SAOT, visualize an overhead snapshot of the resort that freezes all mountain activity on a busy day. Then draw a border around the circulating pod for each lift and count the number of guests. The total of all lift pods is listed in the model that makes up the entire ski resort.
To get a good picture of the entire resort’s SAOT, some designers add 10 to 20 percent to the totals from each lift pod to represent people who are not in the lift/trail system, but are in the lodge or switching rental gear.
In order to better understand each component in the following tables, their makeup is broken down in the following explanations (some are obvious, others are not):
- Capacity, measured in people per hour, represents the existing operating capacity of the lift. It provides the number of skiers and snowboarders that the lift is designed to carry up the hill in one hour.
- Load efficiency directly impacts the effective capacity of the lift. It assumes a reduced percentage of riders loading every available seat on the lift, allowing for slows or stops and is a multiplier of design capacity. In this article, a sliding scale is employed, giving detachable quads as much as a 98 percent loading efficiency down to 80 percent for some fixed grip lifts.
- Skiers per minute is a product of lift capacity and loading efficiency. It provides a measure of how many skiers and boarders can be moved up the mountain each minute.
- Slope length refers to an average trail length for all the trails in the pod.
- Ride time is the lift line length divided by the actual (not design) rope speed.
- Ski time is measured in minutes and provides a time value for skiing back to the maze of the same lift. It is the most complex aspect of the model and is influenced by various factors such as skier ability, terrain difficulty, skier speeds on different terrain, trail grooming, rest intervals, etc. All of these are tossed into a formula and an average estimated time results from objective as well as subjective inputs.
We will assume all the trails are groomed and use a model the SE Group developed for determining how far skiers of different abilities travel on a given slope before they stop to take in a view, wait for friends or rest. The table above provides the speed, slope distance covered in one minute and distance skied between rest intervals for five ability levels. The table assumes a generally accepted standard for rest intervals of one minute each for all skiers and snowboarders. For example, it is estimated that a novice will travel 440 feet per minute and stop for one minute every 750 feet while an expert will cover 2,200 feet per minute and stop for one minute every 2,500 feet. To estimate ski time, divide the slope length by the feet-per-minute figure and add that to the number of rest stops a skier or snowboarder would take on the given slope length. Final ski time is an average result after taking into account the percentages of experts, intermediates and novices that ride the lift and weighting each group accordingly.
- Maze time can be easily adjusted to fit each resort’s expectations. Optimum time might be around five minutes and range up to waits of 20 minutes per lift on peak days.
- Repeat skier is the percentage who generally return to that particular lift pod. Certain lifts, such as those providing transportation out of the base area should be assigned a reduced percentage since some people ride the lift to reach another pod. Commonly, upper-mountain lifts get repeat skiers of 100 percent for most of the day, while transport lifts may see a continuous loss of 30 percent or more of their riders.
The pod’s SAOT, is a measure of how many skiers can be comfortably accommodated by the entire lift/trail system. It is found by adding the ride-time, ski-time and maze-time figures together, multiplying that by the lift capacity and that product by the repeat skier percentage. The formula follows:
skiers per/min x (ride time+ski time+maze time) x repeat skier
To put this model to work in a resort situation, we will use the existing conditions at a resort with three lifts where management is considering a proposal for installing a new detachable quad. (See table below.)
Total lift SAOT for existing conditions on a peak day shows 1,356 skiers at one time. Again, this represents the number of active skiers and snowboarders in the lift lines, the lifts and on the slopes across the entire resort at any given time. As management uses this information, they can get a picture of how many customers their system can handle while maintaining various lift line waiting times.
With the resort’s existing lift conditions analyzed using the model, the new development plan can be evaluated as to whether it meets the goals of the resort.
Ski/Snowboard Time Table
| Ability Level | Skier Speed (mph) | Skier Speed (fpm) | Dist. Before Rest (feet) |
|---|---|---|---|
| Beginner | 5 | 440 | 750 |
| Low Intermediate | 10 | 880 | 1500 |
| Intermediate | 15 | 1320 | 1750 |
| Adv. Intermediate | 20 | 1760 | 2250 |
| Expert | 25 | 2200 | 2500 |
Skier Area Operating Time (SAOT)
| Lift | Type | Capacity S/H | Load Efficiency | Skiers/Min | Slope Length | Rope Speed | Ride Time | Ski Time | Maze Time | Repeat Skier | SAOT |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Lift #1 | Detachable Quad | 2,400 | 95% | 38.00 | 4,961 | 1,000 | 4.96 | 10.4 | 5 | 74% | 573 |
| Lift #2 | Fixed Grip Double | 876 | 85% | 12.41 | 4,722 | 500 | 9.44 | 12.2 | 5 | 100% | 331 |
| Lift #3 | Fixed Grip Triple (adv.) | 1,500 | 90% | 22.50 | 2,950 | 500 | 5.90 | 9.2 | 5 | 100% | 452 |
| Existing Lift Total | 1,356 | ||||||||||
| Lift #4 | Detachable Quad | 1,800 | 95% | 28.50 | 2,474 | 1,000 | 2.47 | 12.2 | 5 | 100% | 561 |
| Proposed Lift Total | 561 | ||||||||||
| PROJECTED SAOT TOTAL | 1,917 |
As seen in the table, the new lift (#4), run at an initial capacity of 1,800pph, would increase the overall SAOT by approximately 40 percent to 1,917. An ultimate design capacity of 2,400pph makes it possible to add chairs at a later date, which will increase SAOT by 33 percent or 187 more guests.
Conducting a “what if” scenario can be interesting, entertaining and beneficial for any average sized mountain. Taking some of the guesswork out of planning and providing insight into existing capacities are the most obvious benefits. As planning trends evolve in our industry, these models may change, but their benefits won’t. Be realistic with your assumptions and the results will generate meaningful comparisons.
