Let It Snow
Landscape Architecture, January 2010
The winter months create both challenges and opportunities for landscape architects.
Many people dread winter. Sure, the first gentle snow is a lot of fun: the kids run out and make snowmen and toboggan runs, and the grown-ups get all dewy-eyed in the chill moonlight. But then comes actual winter, with the ice collecting on the sidewalks, the shoveling, the bundling and unbundling, the extra thirty minutes to get out the door with little ones, and the teeth-chattering cold. Yes, many people dread winter – but not all.
“I have always been struck by the experience and aesthetics of winter,” says Tom Robinson, ASLA. “There’s something about the light and colors. All the senses become engaged more during winter. The acoustics are incredible: the way a blanket of snow can deaden the sound. Sight lines emerge in the cold season that simply aren’t there in summer. All these new things can be revealed, and new connections can be made.”
Robinson’s Robert Frostian paean to the dark months comes despite plenty of practice in one of the snowiest cities in America. He’s a landscape architect with Environmental Design and Research (EDR) in Rochester, NY, which averages 92 inches of snow each year. “I like the challenge of winter,” he says, “The whole world shifts. Places that are very gentle and accessible in the warm season suddenly are a little more exciting and challenging in the wintertime. You have to recognize both sides of a place when you design. Winter causes hardships and accessibility problems that we have to deal with as landscape architects.”
Throughout the United States and Canada, designers are embracing the snow and the ice and the slanting December sun and creating landscapes that work in all seasons. Yet few stories or photos of winter landscapes are being shared in public. Conversations with dozens of designers in regions with long winters revealed that many don’t have a single photograph of their projects in winter. There emerged, however, some common themes, gleaned from images and site visits of projects with excellent winter aesthetics and function, as well as those less successful. Deliberately left out are detailed discussions of plants, for which there are already extensive resources, and of areas of practice that are specialties in their own right, namely ski resorts, winter recreation facilities, and projects in the tundra. Most cold-climate designers have a love-hate relationship with winter (and snow removal crews), but it is a given for them, so they make the best of it.
The idea that winter softens the landscape to its essence is a common sentiment among designers. “Winter is when all the details disappear and you are left with the structure of the landscape,” says landscape architect Cynthia Knauf, who practices in the Burlington, Vermont, area. “It’s the bones of the landscape: the buildings, the stately sugar maple, the grove of birch trees, the stone walls.” In winter the landscape gets rounder, lumpier, and more undulating. It also seems to get bigger. Views open up through deciduous trees and the blanket of white tends to increase scale by eliminating detail. Perhaps the most effective way of counteracting these things is by using structural elements to create points of interest and to enclose and divide space.
Knauf’s design for the Family Mountain Retreat near Stowe, VT, employs a series of rectilinear stone walls to create additional outdoor rooms near the house, which sits within an old 75-acre farm. The landscape, completed in 1996, gives a different view from each room of the house, says Knauf. The view from the living room is of a stone wall that delineates an outdoor room, which mimics the shape of the indoor room. Other walls reach out from the end of the house, then turn at right angles to create terraces. A small wall at the bluff edge becomes more prominent in winter, giving a hard edge to the property. All the walls guide the eye toward distant Mount Mansfield, a natural landmark made even more prominent when the deciduous trees are dormant.
This rectilinear wall-and-terrace motif is not unlike that employed by Coen+Partners at their 2009 ASLA Award-winning Speckman House. According to Shane Coen, ASLA, the main goal of the new design, which was completed in 2007, was to better reflect the architecture of the 1958 California Modern home, and by so doing create a more winter-friendly landscape when viewed from within the house. Coen and landscape architect Stephanie Grotta regraded the backyard into a series of rectilinear terraces and designed a 105-foot long arrow-straight Cor-Ten steel wall. A low (again rectilinear) concrete wall encloses a small courtyard in the front, and other concrete walls hold up the terraces in the back.
Even more formal than either Family Mountain Retreat or the Speckman House is Middlebury College’s Bicentennial Hall, designed by Burlington, Vermont-based H. Keith Wagner, FASLA. “We tend to be minimalists,” he says of his eponymous firm. “There are repetitive elements that we find intriguing, [namely] geometry as an extension of the architecture we are working with.” Each window of the hall looks out on a corridor between white stone walls. Birch trees are casually interspersed amongst the walls. “We’re cognizant of winter when we’re designing,” says Wagner. “How will something look when blanketed in snow?”
The random drifting of snow is an engaging aspect of winter, as are the raw, unpredictable geometries of plants, but for both of those to shine, they should be played off against prominent structural elements. Bicentennial Hall’s river birches have a decidedly non-geometric arrangement; they are sprinkled casually amongst the straight stone walls (and meant to recall the roots of academia: Greek olive tree groves where students would gather and discuss philosophy). They provide a naturalistic counterpoint that makes both design elements stronger. The plaza divides into two fundamental languages: the natural and the constructed. The juxtaposition of the two is a strong aesthetic statement.
Likewise at the Speckman House, Coen+Partners cleared almost all the invasive vegetation from around the terraces and Cor-Ten wall, leaving only several specimen oaks. The largest grows up from the upper terrace, while three others are grouped on the slope just at the end of the wall. Without these trees, the design would be too regimented. They provide, as at Bicentennial, an important foil to the steel and concrete.
Knauf, Coen, and Wagner have used different materials (stone at Family Mountain Retreat and Bicentennial Hall and concrete and steel at Speckman) in a similar structural way, to great effect in all three cases. Each of these projects, in addition, happens to use geometric arrangements, which may be more about the designers’ sensibilities than deliberate winter aesthetics. The key to their winter aesthetic success is the prominence of their structural elements (walls and terraces) punctuated with natural specimens (scattered river birches, landmark oaks, and a distant mountain).
Aesthetics, however, are just part of winter’s intrigue. This is a time to, as EDR’s Tom Robinson puts it, engage all the senses. The sounds are different, the smells are subtle but somehow more poignant, the differences between light and dark, warm and cold are more pronounced. “Even on the coldest day,” says Robinson, “if you can get into a good sun pocket with southern exposure and prevailing winds blocked, it’s going to be very comfortable. It will provide a spot of winter warmth on a cold day.” He believes the only way to catch this variety and subtlety is to do site visits in winter.
For his work at Meridian Fields Ecological Park, a 34-acre nature preserve near Rochester, New York, he did just that. “We went out there and understood where these sun pockets were,” he remembers. “Even from the first sketches they were destinations on our trail maps.” Meridian Fields won a design award from the New York Upstate Chapter of ASLA in 2008, in part because of its winter success.
Meridian’s trail system includes sections of boardwalk with vertical arbor structures. In addition to providing structural elements in the landscape, they also take advantage of the various microclimates Robinson discovered during his initial winter site visits. Some are clustered in the “warm pockets” and encourage people to pause, admire the icicles hanging from their edges, and turn their faces to the warm sun. Some are placed along the pathway itself, to give some interest to the bleaker, colder locations of the park. In these stretches, they tend to pull people along to the next sheltered respite.
At another park in the same Rochester suburb (built two years before Meridian), Robinson used sound to create a winter experience. Corbetts Glen Nature Park, which also won an Upstate New York Chapter design award, is a 51-acre park whose centerpiece is a scenic stream with several small waterfalls. “I went there on a winter site visit to determine the sight lines to the waterfall,” remembers Robinson, “but what was really striking were the acoustics.” The falls are set down in a little glen, and the sound was markedly different at different locations. Even in the dead of winter, the water still runs over the falls, sometimes cloaked by ice. EDR placed the main falls overlook based on an all-season visual experience of the falls. The benches on the overlook, however, are located in the spot with the best winter sound, which is in fact different – somehow more pronounced, says Robinson -- than the summer sound. “This is definitely a winter-oriented overlook,” says Robinson.
Bill Sanders, ASLA, would agree with Robinson’s recommendation to do winter site visits, but for a slightly different reason: functionality. “It will take more time on the ground to understand the space you’re working in,” says Sanders, who is a landscape architect at Marquette, Michigan-based Upper Peninsula Engineers and Architects (UPEA). “In the wintertime you really need to experience the wind blowing across the space, the snow in the air, the traction. The costs for missing something are much higher.”
UPEA is about the only design firm that specifically markets cold-weather design, and they’re in the right location. Marquette gets 140 inches of snow per year and its average January temperature is 12 degrees. The city hosted a Winter Cities Forum in 1997, which Sanders calls a watershed moment for his firm and the surrounding communities. Soon after, the firm led a planning effort for the twin cities of Houghton and Hancock, Michigan, which sit on the Keweenaw Peninsula, that thumb of land that sticks up into Lake Superior. Community surveys found that 80 percnt of the people there found winter as a positive attribute (and where they live, it better be). There were two big negatives, though, says Sanders: “the cold, which we can’t do much about, and mobility, which we can do something about.”
Sanders specifically cites two mobility concerns: slopes and surfaces (“what will a five percent slope do to somebody in the wintertime?”) and snow removal (“where will you pile it all?”). “A typical crosswalk pedestrian ramp,” says Sanders, “can become very slippery. A one-in-twelve slope can be too steep.” He is referring to the standard accessible curb ramp, often with some kind of texturing – slots or truncated domes – that appears at nearly every roadway intersection. Truncated domes don’t handle plowing very well and can trap snow and ice amongst the domes. The slope itself can also be a hazard, especially, says Sanders, if the approach sidewalk is heading downhill to the ramp. He recommends raising street intersections or lengthening the ramp itself to lessen slopes. He actually prefers raised crosswalks instead of ramps, those being easier to plow and having very little slope at all.
Surface materials can also have an effect on safety. Exposed aggregate, rather than providing more grip with its texture, can trap ice and snow and create a very slippery surface. In general, the more heavily textured the exposed aggregate, the more slippery it can become. Luke Sydow, who founded SAS+Associates in Duluth, Minnesota, after six years in Colorado, suggests even concrete should be rethought, installed at higher psi ratings than elsewhere, to prevent spalling. He also says he would always rather use pavers (either concrete or brick), because they hold up to freeze-thaw cycles better than monolithic surfaces and provide good traction. Going one further, permeable pavers, even in the dead of winter, infiltrate some water, which helps the surface stay clear and dry.
In addition to snow and ice making surfaces more hazardous in winter, they can also wreak havoc on constructed elements and plants. Perhaps nowhere have these impacts been more been more comprehensively, scientifically considered than on Nicollet Mall in downtown Minneapolis. This primary downtown commercial thoroughfare was converted to a bus and pedestrian mall in 1968. Lawrence Halprin’s famous winding roadway and groves of pines were replaced in 1990 by a new design by URS Corporation (formerly BRW), for reasons having nothing to do with winter (the design merits of the new design and the very replacement of an iconic Halprin landscape are still hotly debated). In the early 2000s, the local business association commissioned a series of studies of the Mall, which included analyses of winter use. The studies were led by local landscape architecture firm Dahlgren, Shardlow, and Uban (DSU). At that time, the business association was spending $50,000 per year to replace the grout between and under the mall’s granite pavers. The grout was failing primarily due to winter effects: de-icing salts were eroding the joint grout in places and allowing water to penetrate beneath the pavers into the grout setting bed. Once there, the freeze-thaw cycle was destroying the grout from beneath.
To solve the grout issue on Nicollet Mall, DSU (now part of the larger Minnesota firm Bonestroo) first recommended using magnesium chloride salt rather than the more common sodium chloride. It is less corrosive, but interferes with electrical conductivity, so it can’t be used near where the light rail train crosses the mall. So landscape architects Geoff Martin, ASLA and John D. Slack, ASLA, worked with a grout manufacturer to formulate a new product, a hybrid latex-epoxy grout that was installed for the first time in 2003. The jury is still out on whether it will hold up, but initial observation seems to indicate it is doing better than the old stuff.
In addition to the grout degradation, piled snow and salt were also rusting the bases and roofs of bus shelters and other metal elements. After just eight years, quarter-inch-thick tree grate brackets had rusted through, causing the grates to tip and create tripping hazards. Bonestroo’s study included recommendations, including galvanizing the brackets (Martin seems incredulous this wasn’t done in the first place), changing salt type where possible, and including low granite curbs around the tree grates. Raised planter beds appear in many winter cities, most notably Chicago, where they are a great option for keeping damaging salt away from plants. On Nicollet Mall, when new building construction removes and replaces the streetscape, Bonestroo’s recommendations are being followed, including the raised planters. Though the plants need to be irrigated in summer, the tree pits’ underground structure is protected.
As a heavily maintained, urban streetscape, Nicollet Mall was also being affected by winter in another way. The granite planters and light pole bases were being broken by small plows backing into them. Bus shelters were getting dented. This is the conundrum most cold-weather landscape architects face: No designer wants the person in the pick-up truck with the plow on the front to determine the design, but every designer also knows that person is ignored at great risk.
There are, of course, as many different kinds of maintenance equipment as there are winter landscapes to maintain, ranging from the generally benign (though deafening) backpack snowblower to the often destructive truck-mounted plows with sidewalk-clearing swing arms. (In Minneapolis, residential streets are cleared with articulated construction front loaders and dumptrucks.) There are also as many possible design moves as there are possible maintenance regimes. The key, say the winter designers, is not necessarily having a silver bullet for all situations, but rather including winter maintenance as part of the basic inventory and analysis they do for every project.
The result of such assessment, just like any other design inventory, may change the very layout and detailing of the design, may lead to changes in maintenance practices to reflect the preferred design, or (in most cases) may create some compromise between the two. On Nicollet Mall, which is Minneapolis’ highest profile, most expensive streetscape, it would seem better snowplow drivers would be a good option. But, according to Slack, it wasn’t that simple. “Everything had to be re-designed to be hit by a snowplow,” he says. “We kept pushing the issue [with our client]. We said ‘Why don’t you manage the snowplow jockeys? Why don’t you fine them if they hit something?’” The business association said they wouldn’t do that, so DSU designed two prototype light pole bases, one of quarter-inch aluminum and one of precast concrete, and had snow plows run into them. The metal one shattered. (Unfortunately, since Martin and Slack completed their involvement in the project, the old broken granite bases are being replaced with metal ones, for reasons unknown to the two landscape architects.)
The opposite of Nicollet Mall’s robustness is a streetscape design for Hurley, Wisconsin, by Sydow’s SAS+Associates,. Benches and planters are removable. Trash receptacles are raised off the ground and attached to light poles. All of this removal is done primarily to protect the streetscape from snow plowing (and presumably make it easier to plow, as well), but it also mitigates the effect of salt and freeze-thaw on the elements.
It could be argued, however, that the Hurley streetscape throws out the baby with the bath-water, by eliminating likely winter use in the interest of winter maintenance. UPEA’s Bill Sanders would like to see a different approach, especially when it comes to bicycle commuting. He believes bicycle parking needs to be fundamentally rethought in cities with tough winters. Often, maintenance crews will fork-lift racks away and store them until spring, because it is nearly impossible to keep the area around them free of snow with all the bikes in place. While some may argue that commuting by bicycle is unfeasible in the winter months, the winters in many of even the snowiest cities are sprinkled with beautiful snow free days. And some people don’t mind biking when it’s cold. In the U.S. Census Bureau’s most recent transportation survey, Minneapolis, which plows its bike trails, tied for second most trips by bicycle.
In Marquette, Michigan, home of Northern Michigan University (NMU), which can see snow from early November until graduation in early May, removing the racks until spring could mean around two months of bike-commuting opportunity for students. So, a UPEA redesign of NMU’s bike shelter in 2003 utilizes a new type of bike rack. Bikes are stored vertically, so workers can easily plow around and under them. This is, of course, better for both maintenance crews and for bicyclists, who don’t have to contend with plow-drifts that surround bike parking areas after adjacent trails and sidewalks get cleared.
There is also the question of where all that cleared snow gets piled. In urban situations, it’s often taken off site, but smaller sites will need to provide space for it. Sydow’s clients in Colorado often required him to create snow storage plans for submittal along with other plan drawings, and he continues to employ that thinking in snowy Duluth. He recommends keeping the ends of parking lot aisles free of trees so snow can be pushed off the pavement surface. Trees instead can be placed in islands within the lot or along the sides of the parking bays (in front of car bumpers). Cynthia Knauf’s primarily residential portfolio requires other considerations. “You don’t see many intimate courtyard entry gardens in Vermont,” she says. “Where do you put a snow pile eight feet wide and five feet tall? We have to be creative in adding intimacy to the landscape.” On a recent residential project she designed a wall with a removable panel, so snow can be pushed down a hill and away from the main entrance.
All winter-savvy landscape architects – each of whom seems to have his or her own colorful names for winter maintenance crews – recognize that how snow plowing is handled can make or break a project. Most suggest a compromise between understanding the needs of the maintenance crews and changing those maintenance practices for the sake of design. Knauf suggests talking directly with the snow plow operators, and says she’s had some success changing behaviors by including them in the design and making them stakeholders. Slack often recommends his public clients purchase new equipment – like walk-behind brush sweepers -- as an investment in the long-term stability of the design. “Maintenance is as important as design and construction,” says Slack. “Those clients that have successful projects that have lasted, have altered maintenance programs to accommodate design.”
Design for winter has to balance a lot of different factors, including the fact that the design has to work year-round. Good winter designs bring together function and form under a particular set of conditions (snow, ice, cold), then have to succeed again when it’s hot and dry and sunny. All of the landscape architects interviewed for this article had plenty of examples of how they had done this. They seemed to have a lot of tricks up their puffy Gore-Tex sleeves. What they generally didn’t have, however, was actual photographs of their successes.
That’s right, from Maine to Minnesota, there was a surprising dearth of winter imagery. What you’re seeing on these pages is a small sampling of precious little. Even firms such as UPEA that gush about winter and market their winter designs don’t have many shots of their actual product.
Coen+Partners is a notable exception. The firm submitted winter photography with its national ASLA award submittal for the Speckman House, something the jury commended them for. Coen regularly commissions winter photography. “As a firm based in Minneapolis,” he explains, “I’d like to think all of our projects consider winter.”
Winter is the north’s ever-present design hazard. There are no hurricanes up there, a low likelihood of earthquakes, and plenty of water. But the cold and the freeze-thaw cycles and the blowing and drifting snow can wreak the same havoc on design – and do so every year.
But winter can also be moving, as Robinson remembers from his first site visits at Meridian Fields. “It captured my heart,” he says. “A clear blue winter sky, very cold, fresh snow on the ground. Everything about the site was speaking very clearly.”