With the likelihood that catastrophic weather events will continue to increase in frequency and intensity, climate change is at the forefront of many ski industry minds. Take Nevada’s Lee Canyon, for example, where Tropical Storm Hilary dumped nearly 10 inches of rain Aug. 19-20, causing unprecedented flash flooding and landslides that resulted in significant damage to trails, lifts, and the resort’s access road, and forced an end to summer operations. Or look to Vermont, where two days of torrential rain in early July submerged cities and damaged infrastructure at several ski areas, including Stratton, Okemo, and to a lesser extent, Sugarbush. 

Removing the massive amount of material that flowed into the base area at Lee Canyon, Nev., in the wake of Tropical Storm Hilary.

Those ski areas are far from alone in the risk they face from extreme weather events. According to the Fifth National Climate Assessment, a congressionally mandated report that was released in November, the United States experienced 89 billion-dollar weather disasters between 2018 and 2022. 

During the 1980s, by comparison, an average of one billion-dollar event (adjusted for inflation) occurred every four months. The report goes on to state that “the U.S. now experiences, on average, a billion-dollar weather or climate disaster every three weeks.”

Preparing for disaster. Ski areas are starting to acknowledge the increasing threat of catastrophic weather and the important role their stormwater management systems play in minimizing damage and avoiding business interruption. 

Lee Canyon, for one, began upgrading outdated and undersized infrastructure in 2018, during construction of its new base lodge. It aimed to avoid potential issues in the future and meet more stringent stormwater regulations. 

“We saw some minor flood damage in the past, but when we were building a new base lodge, we started to dig in on the engineering side of things,” says general manager Dan Hooper. “[We addressed] measures that were put in during the 1960s and started looking at what we needed to do to ensure we were fixing the problem for the long term.” 

Major remediation work over the last five years includes a $500,000 upgrade to its culvert systems and the replacement of a 24-inch culvert pipe with a 6 ft. x 10 ft. box culvert. The latter seemed like overkill when it was proposed, but it potentially saved the resort from even more extensive damage last summer. 

Ongoing Progress

With its upgrades, the resort appeared to be prepared when Hilary stormed through in August. But the event dumped more than three times the precipitation expected from even a 100-year storm. Could the resulting damage have been avoided? Hooper and Lee Canyon’s civil engineering consultant believe not. 

“[The storm] did make us and our engineer re-look at some pieces, but [there won’t be] real significant changes to what we already had in place,” says Hooper.

Hooper feels the work they did in the past was extremely successful in protecting the base area from further damage. And with the intensity of the historic rain event they experienced, he doesn’t feel it would be feasible to build stormwater and erosion control measures for storms of that magnitude. That said, Lee Canyon will be adding some additional smaller measures, such as more culverts, in the future. 

Ski Area-Specific Challenges

Ski areas face unique challenges when it comes to stormwater management, steep slopes and environmental concerns chief among them. 

Topography. The overall topography of most ski areas makes them susceptible to erosion as a result of stormwater flows. Lee Canyon, for example, is located at the top of a box canyon, which results in stormwater naturally funneling through the base area before continuing through the canyon below. 

At most ski areas, restrictions that come with preserving the natural environment and working within weather windows also create challenges, especially with construction projects.

“Often, you have these steep slopes you’re trying to build on,” says Peter Smiar, a professional engineer and director of land development at Vanasse Hangen Brustlin, an engineering firm that works with several New England ski areas. “Stormwater treatment facilities like retention ponds and treatment wetlands generally need to be in level areas, most of which are already taken up by historic development like parking lots and base lodges.” 

Construction windows and environmental concerns. Short construction windows, difficulty of accessing terrain with heavy equipment, and management of streams, stream buffers, wildlife, and wetlands all pose additional challenges, says Smiar. Not to mention revegetation, which must be done during the growing season to stabilize the soil after conducting earthwork and has to happen earlier than at lower-elevation job sites, shortening the work window even further.  

Upgrades Over Time

Like Lee Canyon, both Sugarbush and Stratton have been slowly tackling upgrades to stormwater infrastructure over the years, which helped them avert even greater failures last summer and will also likely save them money in the long run. 

Sugarbush, for example, has implemented several upgrades over the last decade, such as installing larger culverts, replacing culverts with bridges, planting and increasing the widths of vegetated buffers along streams and brooks, reducing impervious surfaces whenever possible, and installing, regularly inspecting, and maintaining operational stormwater systems. 

Sugarbush, Vt., has invested in improved stormwater infrastructure, such as larger culverts, to minimize flood damage from rain events.

According to Sugarbush director of planning and regulatory compliance Margo Wade, they were lucky the resort was largely spared from significant damage during the July storm, but the upgraded measures are important nonetheless. 

Incremental upgrades. Smiar agrees with that sentiment. “The more folks can accomplish incrementally as they undertake small projects, the less likely they’re going to have a long-term problem where a receiving stream could become classified as impaired, and owners then have to comply with a stricter stormwater management standard that becomes part of the regulations,” says Smiar. 

As stormwater regulations become stricter, he says, ski areas that have completed upgrades over time are less likely to run into permitting issues when tackling future projects. 

Regulations. According to Justin Preisendorfer, eastern region winter sports team manager for the U.S. Forest Service (USFS), the current USFS regulations that apply to ski areas operating on public land are intended to be similar to other state, federal, and municipal regulations. When possible, the USFS utilizes reports, plans, and data that were already prepared for another purpose, like state permitting, easing the burden on ski areas. 

Adapting to change. And while Preisendorfer feels current regulations are working relatively well, he feels ski areas need to remain fluid and go above and beyond to adapt to the changes that come with a changing climate and ecosystem. All ski areas have staff who closely monitor the weather, for example, and can use their findings to develop a plan that outlines specific measures they’ll take in response to predetermined forecasted rainfall amounts.

“If [ski area staff] closely tracks incoming severe weather, they might be able to recognize the scenarios in which they’re most vulnerable,” says Preisendorfer. “Throwing culverts in ahead of a big storm might not be reasonable, but enhancing water bars and adding drainage is. Crews can also do rapid assessment and spot cleaning of culverts and storm drains.” 

Additionally, ski areas have been using advanced methods to model an area’s hydrology when planning new developments. This typically results in the design of culverts, swales, and bridges to handle expected peak flows. However, major storm events in recent years have proven that it’s not just the volume of water, but also the floating debris that needs to be considered. Preisendorfer suggests upsizing culverts and adding drainage during construction that goes above and beyond what’s called for in the plans and specified during hydrologic modeling.    

“We focus on meeting the terms of a permit, but we don’t bake in a reason to truly excel,” says Preisendorfer. “Protecting these opportunities for the future is in everyone’s interest. The insurance companies should be offering rebates for investments that reduce risk to the assets they cover.” 

Preventative Measures

Preparing ahead for events such as those resorts experienced this past summer can be difficult if not impossible, but some ski areas and community organizations, like the Telluride Mountain Village Owner’s Association, are finding creative ways to get ahead of potential failures. 

Slope monitoring. Last spring, heavy rainfall resulted in a 100 ft. x 40 ft. section of slope sliding near a gondola tower at Telluride. In response, a local company, Bulson Surveying, installed a monitoring system that remotely tracks slope movement over time. It consists of surveying lasers and a network of reflector prisms on steel posts and gondola towers that send the data back to Bulson Surveying’s office via cellular data connection every 10 minutes. If movement exceeds a certain threshold, they’ll contact the client and discuss potential options. 

According to owner Dave Bulson, these monitoring systems have been used in several industries, including larger urban construction projects and open pit mines, but can also be an effective indicator of a looming slope failure at points of concern at ski areas.

“There’s typically a slow creep [of soil] until a little crack opens, and then water gets into that crack, and then there’s a bigger release,” says Bulson. “For the monitoring, we set these thresholds that can be indicative of a triggering event—like if it moves more than a quarter inch on any of my monitoring points, I get an email.”

While this technology can help operators understand what’s going on at specific points of concern, such as under cliffs where shallow bedrock may exist or near lift towers, it might not be of much use when it comes to sudden, high-intensity rain events. 

The Whole Picture

To appropriately manage stormwater, it’s important to zoom out and view the ski area as one component of a larger network of waterways and ecosystems that need to be preserved.

“You want to try to maintain the existing hydrology the best you can,” says Smiar. “Because in the mountains, the water flows down towards existing roads and culverts and developments below. So, you have to be mindful of the whole picture,” from where your project is during construction, for example, down to the stream at the bottom.

This is done in a combination of ways, says Smiar, like ensuring there are water bars every 200 feet on open, grassy slopes to capture any sheet flow and redistribute it into forested areas before it concentrates. Sufficiently sized culverts and swales are typically utilized to direct flow. Generally, during construction in particular, the goal is to try to keep the water flowing to where it was going before the project. 

Ripple effects. One thing Jeffrey Cavagnino has learned during his time as Stratton’s senior mountain operations manager is that once you start to see this “top-down” view, you realize that changing something on the mountain—such as building new infrastructure—has a very clear ripple effect. 

“It might not be right at your base, but you really need to follow the water and make sure the stream can handle it,” says Cavagnino. “Because if you send more water down without approval and without working with engineers, you could flood out a golf course or a condo association a mile down the road.” 

And, when stormwater isn’t properly managed, sediment can settle in snowmaking ponds, significantly reducing the efficiency of snowmaking systems.

Some of the measures Stratton has taken in recent years to avoid these issues are upsizing existing culverts, widening swales, and building larger bridges, according to Cavagnino. But, he says, for ski areas to ensure they don’t have issues lower in the watershed, they must be in direct communication with regulatory agencies and engineers to make sure they’re addressing future issues during construction projects. 

Stormwater asan Advantage

Beyond the obvious damage-prevention benefits, stormwater management and erosion control may present opportunities to decrease a resort’s environmental impact as well as save money. 

“How can we use [water] more wisely when it seems like it’s in abundance?” Preisendorfer asks. “I think there are lots of opportunities for better treatment and wiser use of water at ski areas. And some of those things may help with some of the factors that influence climate change.”

He suggests using sediment catch basins for snowmaking and periodically dredging them, using the sediment to sand parking areas and roads rather than shipping it off-site—as long as the sediment is coarse enough to provide traction, and not end up back in the stormwater runoff. 

Some ski areas are already taking on similar projects. Killington, Vt., where a large base area redevelopment is underway, is modifying an existing snowmaking pond to double as a peak flow retention pond during storm events.

Size up. One of the biggest ways to save money is to simply plan for future construction projects as far in advance as possible, according to Smiar.

“When it comes to stormwater management facilities, we usually find that its best to add capacity for future projects that may be coming,” he says. “That way, owners can avoid having to dig out and expand the treatment areas, which can be challenging work.”

He continues, saying that “upgrading to larger, open-bottom crossing structures that can withstand increasingly strong storms and minimize scour around the structure could be the most economical move, despite the daunting up-front costs.”

Exploring ways to reuse captured stormwater, whether for snowmaking systems, irrigation, or even treating it and using it as potable water, are also ways ski areas could reduce their environmental impact. 

Multi-Faceted Investment

Regardless of how often ski areas experience catastrophic events like those that happened at Lee Canyon and across Vermont, or whether ski areas are searching for ways to make use of their stormwater, at the very least, an investment in proper stormwater management and erosion control is an investment in the guest experience.

“I feel like a lot of outdoor recreational activities have some interaction with water at some point, especially with ski areas starting to focus more on four seasons,” says Smiar. “Whether your mountain biking along the brook or fishing, it’s the same receiving water that is affected by a project and that you’re designing BMPs for. And having clean water and protecting natural resources helps add value to the resort.”