Not Just for Drinking Anymore
Artesian wells: engineering a change in how we use natural resources
By Jodi Powers
Think cool thoughts. Throw out all the propaganda you've ever been deluged with through advertising and travel magazines. Now close your eyes and imagine the answer to this question: Where is the largest alpine valley in the world?
|ART COURTESY OF DLR GROUP|
Switzerland? Austria? Germany? France? Italy?
Try the good old U.S. of A.
Spanning more than 8,000 square miles, the San Luis Valley claims the honor of this geographical title. It is also home to the small hamlet of Alamosa, Colo., and its new Family Recreation Center, currently under construction.
Yes, alpine vistas and artesian wells don't just conjure up images of France and Perrier anymore.
Located in south central Colorado at an elevation of 7,544 feet, Alamosa County's high plains and flat valley expand 722 square miles, surrounded by the Sangre de Cristo mountain range to the east and the San Juan mountain range to the west. The legendary Rio Grande River originates in the San Juan Mountains and flows through the San Luis Valley.
Alamosa, a town of 8,775, encourages its nature-loving citizens to enjoy Alamosa's natural resources while ensuring that man-made buildings are designed with the most environmentally sensitive applications possible.
Such is the case for the new Alamosa Family Recreation Center, slated to open next summer. At 27,500 square feet, the center is one of the largest undertakings by the city in recent memory. Funded by a bond issue, the new recreation complex will offer everything from childcare to a cardiovascular room to a future-phased full-sized lap pool. Perhaps most impressive is a geothermal artesian well that provides the heating source for this facility.
Alamosa has some of the coldest temperatures on record in the nation, so designing for a harsh climate was always in the forefront.
Close to the family recreation site is an existing geothermal artesian well. A symbiotic relationship exists in order to keep the well in operation. Gary Nelson, the project's mechanical engineer, explains the well was designed to pump 130 gallons of 92-degree water per minute. The water is pumped into a heat exchanger, where the water is stripped of its heat and cooled to 78 degrees.
Water pumped through the heat exchanger is then cycled through an under-floor radiant heating system that uses cross-linked polyethylene or EPDM tubing (ethylene propylene dieneter polymer or it's also known as hydronic thermal tubing) buried in the floors to transfer heat to the building. The in-floor radiant heating is used throughout the building in 11 zones, making the system more efficient and flexible. Using the free energy will allow the City of Alamosa to cut down its energy costs, adds Nelson, who designed Alamosa's mechanical engineering system.
"Under-floor radiant heat is a very consistent heat, which is good for a facility like this because it's operating so many hours a day, and you want the temperature to remain fairly consistent and not have too much fluctuation in the temperature," says Ed Bledowski, a principal in DLR Group's Farmington, N.M., office.
Alamosa also will use the geothermal water to heat the air coming into the building.
"We use that same water and supplement it with gas heat from the gas boiler," says Nelson, a mechanical engineer with DLR Group's Phoenix office. In addition to providing the heat to ventilate the air required for the building, the full-size, natural gas-fired forced hot water boiler system also provides a heat backup system.
The under-floor radiant heating system is coordinated with three different flooring applications:
- flexible piping in the sleeper space under the wood-floored gymnasium
- flexible or rigid piping in the concrete beneath the rubber-floored multipurpose room flooring
- flexible or rigid piping in the concrete beneath the concrete on carpeted or tiled floors.
Included in the master plan is a pond, which is where the water will be channeled after it's stripped of its BTUs. The pond has dual purposes. It will provide an aesthetic water feature on the site and allow people to enjoy activities like fishing and ice skating. The pond will also serve as an irrigation source for the baseball, softball and soccer fields located north of the pond.
"We're really utilizing it in the most efficient and green way we can," Bledowski says.
Ringed above the full-height gymnasium and adjacent multipurpose room is a unique second-level running track. Other spaces in the complex include a training/meeting room, arts-and-crafts activities classroom, showers and lockers, and administration spaces for the parks and recreation staff.
The facility is designed with expansion in mind, as the city has hopes for growing this initial program in years to come with additional education, recreation and aquatics areas.
Alamosa's new facility will unite multiple programs under one roof. Currently, Alamosa's schools and other buildings in disrepair were retrofitted into recreation facilities for the community. Housing multiple programs in so many facilities has made it difficult for the city of Alamosa to control and operate its programs, Bledowski says.
"They were just 'making do' over the years," he adds.
Another feature unique to Alamosa is its forward planning.
"Some of the things that we have here that doesn't exist in other facilities are full-blown toilet/locker/shower facilities," says Bledowski, explaining that they have been designed and laid out for expansion to accommodate a future pool, which has been master planned to be phased in at a later date.
The DLR Group teamed with Mark Jones, a local San Luis Valley architect who also served as a historical consultant. Jones' close proximity to the project site and rapport with the city added for a smooth-running project.
One of the features through the main entry is a soaring, central gallery that is directly aligned with the main entrance, reception area and lobby. This area will house various historical mural photographs of Alamosa's history. The gallery space will be a triple-loaded corridor, providing access to the classrooms, gym and stairway to the upper-level running track. Clerestory windows, cable-mounted light fixtures and suspended fabric sculptures will animate this grand space. Similar to the exterior, stone columns line the walls from the entry inward.
The exterior, as dictated by available funding, is simple and economical: exterior insulation and finish system (EIFS) as a wall finish, metal roofing, wood-framed porch canopies and stone-clad steel columns are the material elements used to create this large facility. The bulk of the steel structure is a prefabricated system with a minimum of custom work around the public entry.
Of course, the facility's unique geothermal artesian well heating system is what sets it apart, illustrating another one of nature's answers to green design.
Jodi Powers is a senior associate at DLR Group Marketing in Phoenix. She can be reached at firstname.lastname@example.org.