Hot Spots, Hot Water
Geothermal springs offer respite in the Chilean desert and Patagonia.

By Jimena Martignoni

Two successful landscape architecture projects are located on opposite ends of Chile: the Puritama Hot Springs (Termas de Puritama) and the Geometrical Hot Springs (Termas Geométricas). The sites of the two springs reflect the landscape diversity of Chile: from the world’s driest desert, the Atacama Desert in the north, to the exuberant woods and blue lakes of Patagonia in the south, along the country’s approximately 2,700-mile length. However, there is a dominant physical feature that extends that entire length, from the Bolivian plateau to Tierra del Fuego, visually and geologically connecting many Chilean landscapes: the Andes. As part of this mountain system, hot springs are dispersed throughout the country.

The two hot springs projects are the work of one designer who is highly respectful of local natural attributes. Germán del Sol is a Chilean architect whose projects have involved landscape design. He has been shifting his architect’s vision to become more open and inclusive, focusing on site-specific design. After studying in Barcelona and working in the different regions of Chile, he has become one of the country’s most recognized designers. Del Sol’s design for the hot springs takes advantage of four natural features: the northern desert, the southern lakes, the Andean mountains, and the geothermal waters.

The thermal baths in the northern desert are an unexpected gift much appreciated by locals and visitors: a subtle line of water and life hidden in one of the driest places on Earth. Conversely, the thermal baths in the southern woods are an overwhelming experience of water—a flowing river, pools, steam, and, if one gets lucky, a refreshing rain in summer or a light snow in winter.

Puritama Thermal Springs

The Puritama thermal baths are 21 miles from San Pedro de Atacama, an oasis 8,000 feet above sea level created by the rainfall of the Bolivian altiplano winter in the Atacama Desert. In the middle of a landscape of arid mountains colored in red, ocher, and sepia (depending on the morning, noon, or evening light), the town of San Pedro emerges as an isolated green node of life.

This city, first settled by the atacameños—a local farming culture—was conquered in 1425 by the Incas and then by the Spaniards in 1535. While the Chilean community at large does not have a completely mature environmental awareness yet, small towns like this one are starting to take good care of their cultural and natural heritage.

The Puritama geothermal river flows along an almost 1,000-foot-deep crack carved in the rocky desert mountains, bubbling out as springs at 86 to 92 degrees Fahrenheit. The name Puritama actually comes from puri, which means water, and tama, which means hot.

When del Sol visited the site for the first time, it was basically a 1,650-foot-long crack along which the river flowed and where the riverbanks were covered with Andean pampas grass or cola de zorro (Cortaderia atacamensis), an ornamental native plant. Along this linear natural system, some pools of hot water carved out by local people in ancient times remain, along with two adobe buildings (kayankas) near the site’s entry point that were constructed by the Incas when they conquered northern Chile.

This scene is what del Sol worked with after the land was bought by the Atacama’s Explora Hotel. He proposed the Pueblo Atacameño Council as the managing organization for running and taking care of the site. Archaeologist Carlos Aldunate del Solar, director of the Pre-Columbian Museum in Santiago, was the specialized consultant at the site who worked hand in hand with del Sol.

The Puritama Thermal Springs make reference to the atacameños culture with white-painted dressing rooms that echo the emblematic white architecture of the town of San Pedro de Atacama. A wooden boardwalk crosses the site about one foot above river level, allowing the grass underneath to grow and giving visitors access to the different pools and resting spots. When the boardwalk reaches the pools, it widens and creates small terraces that face the water so people can sunbathe or just rest.

The eight pools were broadened, deepened, and partly covered with stone walls. As a consequence of the drip irrigation system that was added by the designer, the Andean pampas grasses now grow exuberantly in thick masses that hide the stone structures, while their silver crests attract light and create a mystical effect during certain times of the day.

Two minimalist-looking white box-shaped buildings stand close to the main access, each of them offering a bathroom, a dressing room, and a sauna. The same small collecting pool that feeds the irrigation system provides running water.

The kayankas, or small Incan shelters, were restored and rehabilitated as administration offices, and new straw roofs were added that are reminiscent of the original construction materials.

Seen from the road that goes down the mountain slopes, the site is presented as a whole, a green strip of tall grasses crowned by white-silver crests and crossed by a long, narrow path that gets lost in the vast arid landscape. The path, painted dark red, creates a major color contrast with the grasses and with the sepia and gray hues of the enclosing mountains.

The site’s parking area is on a plateau at the same level as the site itself. From here, visitors leave their cars and step onto the boardwalk entry point surrounded by the tall Andean pampas grass, which screens each turn the boardwalk makes. Visitors literally discover the pools and the terraces shaped by the boardwalk while walking it. Some terraces are completely surrounded by the Andean grasses, making them isolated, intimate spots from which the view is reduced to the blue of the sky and the surrounding mountains. Others are framed by the grasses in a more open manner, creating wider vistas of the site.

Inside the pools the water is warm, the small waterfalls that most of them have act as natural massage showers, and the sun feels strong on your face. (Solar radiation in Atacama is really high, and many white-skinned Americans and Europeans go back home at the end of the day completely relaxed but badly sunburned if they forgot their sunscreen!)

Accessing the site requires a $10 entrance fee, which includes the use of all amenities for the day. However, the atacameños people, who had historically “owned” the springs, have free admission to these thermal baths.

The construction of Puritama took no more than three months, but the installation of the drip irrigation system and the restoration of the Incan shelters, which were done in phases, delayed the finish. The site was opened to the public in 2000.

Both the design and construction were a 100 percent in situ process in which del Sol, together with other people from his office, worked at the site marking the boardwalk’s exact placement with ropes and then translating the design onto paper.

In San Pedro de Atacama, farming areas take turns being watered; common cisterns that are part of a system of channels fed by local rivers provide water on a very rigid schedule that everyone respects. The urban area has running water only during the day. In contrast, the Andean woods of Patagonia or “area of the lakes,” as it’s called in Chile, benefits from a great deal of water—as much from an ecological perspective as from a visual one.

Geometrical Thermal Springs

These thermal baths are located 62 miles from Pucón, one of the most beautiful Patagonian cities in Chile, situated by the still-active Volcano Villarrica. From Pucón two different roads can be taken, one of them only possible with a four-wheel-drive vehicle, both going up to 6,500 feet, where the springs flow.

Del Sol discovered the site after a 15-year search following Spaniards’ chronicles that described mystical sites with geothermal waters.

The site is a 1,800-foot-long stony canyon. He hardly noticed the river waters that run through this linear canyon when he first surveyed the site, because the length of it was covered with dirt, stones, and logs. The land belonged to a private logging hacienda, one of the few remaining inside the 156,000-acre Villarrica National Park.

In 2002, del Sol rented the place with a 30-year lease and began clearing it out, a process that took a whole year and filled more than 100 trucks with trash and dirt. As a result, the river started flowing faster and moving an average of five gallons of water per second, when previously it moved fewer than one.

To accomplish a sound environmental excavation, del Sol worked with a team of mine engineers, hydrologists, and geologists. To find the exact location of the springs they used thermometers that indicated the spots where the land was hotter. Digging carefully at those locations, they marked 60 hot water pools where the temperature is approximately 185 degrees Fahrenheit.

The Geometrical Thermal Springs owe their name to the geometrical configuration of the site, which is set against the luxuriant organic lines of the wilderness setting. “I wanted to tame nature, but at the same time emphasize it,” says del Sol. “This is a space framed by a wild environment that I intended to make livable, but I also meant to stress disparity.”

One of the biggest differences from Puritama was that when the conceptual layout started taking form, no pools existed, and del Sol knew he had to design them from scratch. Referring to the intentional contrast of the new design with traditional natural forms, he says, “Designing them as if they had been naturally shaped made no sense, so that’s when I decided to apply geometry and lay them out as geometrical pools, surrounded by geometrical shapes.”

To take better advantage of the strong natural setting, the geometrical pools are placed on both sides of the central boardwalk, facing the canyon’s walls. Concavities in the canyon walls outline the pools’ inner sides.

Del Sol intended to create a self-contained space accessed by a “round-trip” circuit, with just one entrance through which people enter and leave the site. The space is therefore physically contained not only by the canyon’s stony walls, which are impossible to climb, but also by the man-made structure of the boardwalk.

The humidity generated by the water and steam has led to the walls being covered with lush green vegetation native to the area. Large ferns, mosses, and philodendron species wrap the stone, crowned by the typical coihue forest (Nothofagus dombeyii or southern beech) of Patagonia.

Del Sol uses old Mapuche (Patagonian aboriginal groups) techniques to regulate temperature and to channel the water using gravity. “Routing the water all through the site with a typical sealed piping system would not match the site’s concept and, even worse, would turn into a problem for cleaning, maintenance, and heat loss,” says del Sol. “What is inherent to hot springs is that they keep the heat while openly flowing.”

The thermal water is collected from every one of the 60 springs by polypropylene tubes that feed to a main wooden open channel that runs right underneath the central boardwalk, all along the site. This keeps the boardwalk warm even during cold days, and a light steam is constantly rising into the air.

The flowing water in the main central channel, with a temperature up to 185 degrees Fahrenheit, is circulated to five retention pools through wooden closed distributors. Once the reposing water there cools down to approximately 102 degrees, it’s sent through the same kind of channels to 12 bathing pools.

The pools are cleaned every three days to maintain them and prevent health problems. They are emptied at four in the morning and cannot be used until the afternoon, when the temperature is appropriate for bathing, so the cleaning schedule is rotated to keep some pools in use while others are being cleaned.

The central boardwalk runs along the entire site following the natural topography, making some angular turns that make the walk and the scene more dramatic. As in Puritama, the boardwalk is painted red, but here the grass-roofed dressing rooms are also painted in that color. To one side of the boardwalk, the cold river water flows constantly without mixing with the water of the hot springs. After bathing in the pools, visitors have the option of going into the river.

At the Termas Geométricas, the experience of the site is one of adventure, mystery, and literal fogginess. Just getting to the site involves a long drive. Once there, visitors leave their cars and walk five minutes to the entrance, where they are provided with towels and keys to lockers located inside the dressing rooms. People walking up and down the boardwalk, bathing, or chatting; the steam filling up the environment; the green fully covering the canyon walls and contrasting with the red of the central boardwalk; and the super hot water of the pools all create a fantastic experience for the senses.

Even though the long ride through the Patagonian woods and towns is well worth the experience, one could argue that accessibility to both sites is limited to those who have a car or can afford a ride up there, but generally speaking, people gather in groups and find ways to make the trip less expensive. In February, during the Chilean summer break, the number of visitors to the Geometrical Thermal Springs can reach up to 280 persons per day; the rest of the year the number goes down to an average of 50.

After the long ride it takes to get to these sites, visitors perceive them almost as “hidden treasures.” But they shouldn’t be, for water is, literally, a precious source of life. The issue that arises here is to what extent these sites should be more accessible and how local governments could become more involved in this kind of development in Latin America.

Jimena Martignoni is an independent landscape architect and researcher in Buenos Aires, Argentina.

Awards

The Puritama Thermal Springs have received several awards, including an honorable mention at the 12th Biennial of Architecture of Quito, Ecuador, in November 2000; a gold medal in 2001 at the International Architecture Biennial of Miami; and the 2001 Arup World Architecture Award for Best Project in Central/ South America.

The Geometrical Thermal Springs earned first place in the 14th Architecture Biennial of Santiago, Chile, in November 2004, and took the Grand Prix of the Landscape Architecture Look from Home exhibition and competition held at Dom na Brestskoy in Moscow in October 2005.

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